ML20028F082: Difference between revisions

From kanterella
Jump to navigation Jump to search
(StriderTol Bot insert)
 
(StriderTol Bot change)
 
Line 2: Line 2:
| number = ML20028F082
| number = ML20028F082
| issue date = 08/31/1980
| issue date = 08/31/1980
| title = Single Loop Operation.
| title = Single Loop Operation
| author name =  
| author name =  
| author affiliation = GENERAL ELECTRIC CO.
| author affiliation = GENERAL ELECTRIC CO.
Line 17: Line 17:


=Text=
=Text=
{{#Wiki_filter:.. _       ___ _ _ . _ . . _ _  .      _ _ _ _ _ . . _ _ _ _ _    __ _ _  - - , -
{{#Wiki_filter:.. _
        !                                                                                NEDO 24281
NEDO 24281 80N ED28's CLASS 4 I
        '                                                                                  80N ED28's CLASS 4 I                                                                               AUGUST 1980 I
AUGUST 1980 I
k i
k i
FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION             l 1
FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION l
l u
9:
Is it n u m a s s u m e s. u m ~ m ,z m m . - - m                                    _ _ ,              4:
1 l
1 l
          $882258c2o!884%
u 9:
P                            PDR GEN ER AL h ELECTRIC
Is it n u m a s s u m e s. u m ~ m,z m m. - - m 4:
1 l
$882258c2o!884%
GEN ER AL h ELECTRIC P
PDR


4 i                                                                                                                                                                                                                           f
4 i
          ;*                                                                                                                                                                      NEDO-24281 l                                                                  ,
f l
;                                                                                                                                                                                  80NED285 j                                                                                                                                                                                     Class I l                                                                                                                                                                               August 1980 I
NEDO-24281 80NED285 j
9 i, et                                                                                                                                                                                                                         I
Class I l
]l 1       ,
August 1980 I
t j i                                                                                                                                                                                                                           f 1I                                                                                                                                                                                                                            i i                                                                                                                                                                                                                     i f*
9 i, et I
i,
] l 1
* t
t j i f
* i                                                               FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION l
1 I i
I d
i i
I.
f*
i, t
i FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION l
I I
d I.
l l
l l
l                                                                                                                                                                           .
l
.I I
.I I
i
i
(
(
l                                                                                                                                                                                                                              I i
l I
l I
l I   .
i l
I f
I l
I I
f t
t t
t t
t i '
i '
i i                                     NUCLEAR POWER SYSTEMS OlVi$lON e GENERAL ELECTRIC COMPANY l                                                             SAN JOSE, CAllFORNI A 95125 i I   e i
i i NUCLEAR POWER SYSTEMS OlVi$lON e GENERAL ELECTRIC COMPANY l
' s I,                                                       GEN ER AL $ ELECTRIC L                                                                                                                                                                                                                       -
SAN JOSE, CAllFORNI A 95125 i I i
e
' s I,
GEN ER AL $ ELECTRIC L
i
i
                                        ,--,.,..,--,,,,,-...-v         ,,,----r
-----vm---vv--.e w---- -. --
                                                                                      ---%-.cw+.--m---#,--,-w.---.~.                                         my--y'-
,--,.,..,--,,,,,-...-v
* 3,,   - - + . - ++-e e-~m--_---+ -- g-y----
,,,----r
---%-.cw+.--m---#,--,-w.---.~. my--y'-
3,,
- - +. -
++-e e-~m-- ---+
g-y----


l     .
l q
q     -
f.
: f.                                       NEDO- 24281
NEDO-24281
    ?
?
t I
t I
DISC: AIMER GF RESPONSIBILITY j         Ynia doxer:ent was prepared by or for the General Electric Company.
DISC: AIMER GF RESPONSIBILITY j
Neither the General Electric Cor:pany nor any of the contributors to i         this doc: cent:
Ynia doxer:ent was prepared by or for the General Electric Company.
l i         A. Makaa any varranty or representation, express or implied, with recpect to the accuracy, completeness, or usefulness of the           1 infomation contained in this doc: cent, or that the use of any 3
Neither the General Electric Cor:pany nor any of the contributors to i
infcmaticn dicolosed in this document may not infringe privately l
this doc: cent:
t             cuned rights; or                                                       '
l i
I I
A.
    !        B.
Makaa any varranty or representation, express or implied, with recpect to the accuracy, completeness, or usefulness of the 1
i              Ascumca any responsibility for liability or damage of any kind         h uhich may result from the use of any infomation disclosed in
infomation contained in this doc: cent, or that the use of any infcmaticn dicolosed in this document may not infringe privately l
  ,              thia document.
3 t
cuned rights; or I
I B.
Ascumca any responsibility for liability or damage of any kind h
i uhich may result from the use of any infomation disclosed in thia document.
i 4
i 4
W ii
W ii
                                                                                      .e
.e


l g _ _ __                                                                 N G
g _ _ __
NEDO-24281 TABLE OF CONTENTS Page l-1
N G
: 1. INTRODUCTION AND  
NEDO-24281 TABLE OF CONTENTS Page l-1 1.
INTRODUCTION AND  


==SUMMARY==
==SUMMARY==
 
2-1 2.
2-1
MCPR FUEL CLADDING INTEGRITY SAFE"IY LIMIT 2-1 2.1 Core Flow Uncertainty 2.1.1 Core Flow Measurement During Single Loop 2-1 Operation 2-2 2.1.2 Core Flow Uncertainty Analysis 2-4 2.2 TIP Reading Uncertainty i
: 2. MCPR FUEL CLADDING INTEGRITY SAFE"IY LIMIT                 2-1 2.1   Core Flow Uncertainty 2.1.1   Core Flow Measurement During Single Loop 2-1 Operation                                 2-2 2.1.2   Core Flow Uncertainty Analysis             2-4 2.2   TIP Reading Uncertainty                                     i 3-1     -
3-1 3.
: 3. MCPR OPERATING LIMIT                                     3-1 3.1   Core-Wide Transients                               3-2 3.2     Rod Withdrawal Error                               3-4 3.3     MCPR Operating Limit 4-1     .
MCPR OPERATING LIMIT 3-1 3.1 Core-Wide Transients 3-2 3.2 Rod Withdrawal Error 3-4 3.3 MCPR Operating Limit 4-1 4.
: 4. STABILITY ANALYSIS                                                 ,
STABILITY ANALYSIS 5-1 5.
5-1
ACCIDENT ANALYSES 5-1 5.1 Loss-of-Coolant Accident Analysis 5-1 5.1.1 Break Spectrum Analysis 5-2 4
: 5. ACCIDENT ANALYSES                                         5-1 5.1     Loss-of-Coolant Accident Analysis                 5-1     ,
5.1.2 Single-Loop MAPLHGR Determination 1
5.1.1   Break Spectrum Analysis                   5-2   4 5.1.2   Single-Loop MAPLHGR Determination                 1 Small Break Peak Cladding Temperature      5-2 5.1.3                                             5-2 5.2   One-Pump Seizure Accident 6-1 6.
5-2 5.1.3 Small Break Peak Cladding Temperature 5-2 5.2 One-Pump Seizure Accident 6-1 6.
REFERENCES h
REFERENCES h
I r
I r
t i
ti
                                                                          ]i d
]
i d
ii1/1v 1
ii1/1v 1
s
s


    .                                  NED0-24281 TABLES Table                           Title     Page 5-1 MAPLilGR Multiplier Cases             5-5 5-2 Limiting MAPLHGR Reduction Factors   5-5 I
NED0-24281 TABLES Table Title Page 5-1 MAPLilGR Multiplier Cases 5-5 5-2 Limiting MAPLHGR Reduction Factors 5-5 I
l l
?
l
                                                            ?
I l
I l
I I
I I
i l
i l
                                                            )
)
1 4
1 4
i 9
i 9
Line 109: Line 127:
v/vi
v/vi


                                                                                  'mi NEDO-24281 ILLUSTRATIONS Title                         Pg Figure Illustration of Single Recirculation Loop Operation Flows   2-5 2-1 Main Turbine Trip With Bypass Manual Flow Control           3-5 3-1 4-1    Decay Ratio Versus Power Curve for Two-Loop and Single-     4-2 Loop Operation FitzPatrick Discharge Break Spectrum Reflood Times         5-6 5-1 FitzPatrick Discharge Break Spectrum Uncovered Times       5-7 5-2 FitzPatrick Suction Break Spectrum Reflood Tines           5-8 5-3 FitzPatrick Suction Break Spectrum Unco *ered Times         5-9 5-4 l
'mi NEDO-24281 ILLUSTRATIONS Title Pg Figure 2-5 Illustration of Single Recirculation Loop Operation Flows 2-1 3-5 3-1 Main Turbine Trip With Bypass Manual Flow Control Decay Ratio Versus Power Curve for Two-Loop and Single-4-1 4-2 Loop Operation 5-6 5-1 FitzPatrick Discharge Break Spectrum Reflood Times 5-7 5-2 FitzPatrick Discharge Break Spectrum Uncovered Times 5-8 5-3 FitzPatrick Suction Break Spectrum Reflood Tines 5-9 5-4 FitzPatrick Suction Break Spectrum Unco *ered Times l
l                                                                                     E' 51 e
l E'
i 1                                                                                         :
51e i
\
1
\\
A L
A L
l l
l l
vii/viii
vii/viii


g-        ~~~,.--.n               . . _ . . .
~~~,.--.n w
w
g-NEDO-24281 1.
* NEDO-24281
INTRODUCTION AND  
: 1.       INTRODUCTION AND  


==SUMMARY==
==SUMMARY==
 
FitzPatrick Nuclear Power Plant technical specifications for the
FitzPatrick Nuclear Power Plant The current technical specifications for the
=
                                                                                                              =
The current operation beyond a relatively short period of time if an do not allow plant be returned to service. The FitzPatrick idle recirculation loop cannot (Technical Specification 3.6.Gl shall not be operated Nuclear Power Plant for a period in excess of 24 hours with one recirculation loop out of service.
do not allow plant operation beyond a relatively short period of time if an idle recirculation loop cannot be returned to service. The FitzPatrick (Technical Specification 3.6.Gl shall not be operated Nuclear Power Plant for a period in excess of 24 hours with one recirculation loop out of service.
reduced power with a single recirculation loop The capability of operating at in is highly desirable, from a plant availability / outage planning standpoint, d
reduced power with a single recirculation loop The capability of operating at                                                                 in is highly desirable, from a plant availability / outage planning standpoint, d
the event maintenar.ce of a recirculation pump or other component ren ers one To justify single-loop operation, the safety analyses docu-loop inoperative.
the event maintenar.ce of a recirculation pump or other component ren ers one loop inoperative. To justify single-loop operation, the safety analyses docu-               d mente'd in the Final Safety Evaluation Reports and Reference 1 were reviewe for one-pump operation.        Increased uncertainties in the core total flow and TIP readings resulted in an 0.01 incremental increase in the MCPR fuel cladding This 0.01 increase is integrity safety limit during single-loop operation.
d mente'd in the Final Safety Evaluation Reports and Reference 1 were reviewe Increased uncertainties in the core total flow and for one-pump operation.
reflected in the MCPR operating limit. No other increase in this limit is required as core-wide transients are bounded by the rated power / flow analyses performed for each cycle, and the recirculation flow-rate dependent rod block and scram setpoint equations given in the technical specifications are adjusted for one-pump operation. The least stable power / flow condition, achieved by is not affected by one-pump operation.           ,
TIP readings resulted in an 0.01 incremental increase in the MCPR fuel cladding This 0.01 increase is integrity safety limit during single-loop operation.
tripping both recirculation pumps,                                                               L b
No other increase in this limit is reflected in the MCPR operating limit.
h the flow control should be in master manual, During single-loop operation,                                                                     h since control oscillations might occur in tne recirculation flow control system under automat!c flow control conditions.
required as core-wide transients are bounded by the rated power / flow analyses performed for each cycle, and the recirculation flow-rate dependent rod block and scram setpoint equations given in the technical specifications are adjusted The least stable power / flow condition, achieved by for one-pump operation.
0.84, 0.35, and 0.84 for the 7x7, 8x8, Derived MAPLHGR reduction factors are                                                               '
is not affected by one-pump operation.
and 8x8R r ue ! types, respectively.
tripping both recirculation pumps, L
b h
the flow control should be in master manual, During single-loop operation, h
control oscillations might occur in tne recirculation flow control since system under automat!c flow control conditions.
0.84, 0.35, and 0.84 for the 7x7, 8x8, Derived MAPLHGR reduction factors are and 8x8R r ue ! types, respectively.
The dis-The analyses were performed assuming the equalizer valve was closed.
The dis-The analyses were performed assuming the equalizer valve was closed.
if its charge valve in the idle recirculation loop is normally closed, but closure is prevented, the suction valve in the loop should be closed to prevent of a postulated the loss of Low Pressure Coolant Injection (LPCI) flow out break in the idle suction line, 1-1/1-2 I,
if its charge valve in the idle recirculation loop is normally closed, but closure is prevented, the suction valve in the loop should be closed to prevent of a postulated the loss of Low Pressure Coolant Injection (LPCI) flow out break in the idle suction line, 1-1/1-2 I,


_-g--~-.__-
_-g--~-.__-
NED0-24281
NED0-24281 2.
: 2. MCPk FUEL CLADDING INTEGRITY SAFETY LIMIT Except      for core total flow and TIP reading, the uncertainties used in the ctatistical analysis to determine the MCPR fuel cladding integrity safety limit are not dependent on whether coolant flow is provided by one or two racirculation pumps. Uncertainties used in the two-loop operation analysis are documented in the FSAR for initial cores and in Table 5-1 of Reference 1 for reloads. A 6% core flow measurement uncertainty has been established for As shown eingle-loop operation (compared to 2.5% for two-loop operation).
MCPk FUEL CLADDING INTEGRITY SAFETY LIMIT for core total flow and TIP reading, the uncertainties used in the Except ctatistical analysis to determine the MCPR fuel cladding integrity safety limit are not dependent on whether coolant flow is provided by one or two Uncertainties used in the two-loop operation analysis are racirculation pumps.
documented in the FSAR for initial cores and in Table 5-1 of Reference 1 for A 6% core flow measurement uncertainty has been established for reloads.
As shown eingle-loop operation (compared to 2.5% for two-loop operation).
below, this value ccuservatively reflects the one standard deviation (ene sigma) accuracy of the core ilow measurement system documented in Reference 2.
below, this value ccuservatively reflects the one standard deviation (ene sigma) accuracy of the core ilow measurement system documented in Reference 2.
The random noise component of the TIP reading uncertainty was revised for single recirculation loop operation to reflect the operating plant test results given in Subsection 2.2 below. This revision resulted in a single-loop opera-The comparable tion process computer uncertainty of 9.1% for reload cores.
The random noise component of the TIP reading uncertainty was revised for single recirculation loop operation to reflect the operating plant test results given in Subsection 2.2 below. This revision resulted in a single-loop opera-The comparable tion process computer uncertainty of 9.1% for reload cores.
The net two-loop process computer uncertainty value is 8.7% for reload cores.
The net two-loop process computer uncertainty value is 8.7% for reload cores.
effect of these two revised uncertainties is a 0.01 incremental increase in the required MCPR fuel cladding integrity safety limit.
effect of these two revised uncertainties is a 0.01 incremental increase in the required MCPR fuel cladding integrity safety limit.
2.1 CORE FLOW UNCERTAINTY Core Flow Measurement Durine Single Loop Operation                                     Cl 2.1.1                                                                                                             l l
2.1 CORE FLOW UNCERTAINTY Cl Core Flow Measurement Durine Single Loop Operation l
The jet pump core flow measurement system is calibrated to measure core flow when both sets of jet pumps are in forward flow; total core flow is the sum of the indicated loop flows. For single-leop operation, however, the inactive                                 5 jet pumps will be backflcwing. Therefore, the measured ficw in the backflowing                             -
2.1.1 l
In jet    pumps must be subtracted from the measured ficw in the active loop.                                   i addition, the jet pump flow coefficient is different for reverse flow than for
The jet pump core flow measurement system is calibrated to measure core flow when both sets of jet pumps are in forward flow; total core flow is the sum of the indicated loop flows. For single-leop operation, however, the inactive 5
Therefore, the measured ficw in the backflowing jet pumps will be backflcwing.
In pumps must be subtracted from the measured ficw in the active loop.
i jet addition, the jet pump flow coefficient is different for reverse flow than for and the measurement of reverse flow must be modified to account
[
[
f orward flow,                 and the measurement of reverse flow must be modified to account              ;
f orward flow, for this difference.
for this difference.                                                                                           I f
I f
For single-loop operation,                    the total core flow is derived by the following i
the total core flow is derived by the following For single-loop operation, i
fo rmula:                                                                                                 l Inactive Loop                             }
fo rmula:
Total       Core}   ,    Active Loop j - C IndicatedFlow}.                             '
l Inactive Loop
Flow  ,      Indicated Flow /
}
2-1                                                 $
Total Core}
N
Active Loop j - C IndicatedFlow}.
Indicated Flow /
Flow 2-1 N


wasr -                 .c -     .
wasr -
.c -
NEDO-24281 where C (= 0.95) is defined as the ratio of " Inactive Loop True Flow" to
NEDO-24281 where C (= 0.95) is defined as the ratio of " Inactive Loop True Flow" to
        " Inactive Loop Indicated Flow," and " Loop Indicated Flow" is the flow indi-cated by the jet pump " single-tap" loop flow summers and indicators, which are set to indicate forward flow correctly.
" Inactive Loop Indicated Flow," and " Loop Indicated Flow" is the flow indi-cated by the jet pump " single-tap" loop flow summers and indicators, which are set to indicate forward flow correctly.
The 0.95 factor was the result of a conservative analysis to appropriately modify the single-tap flow coefficient for reverse flow.* If a more exact, less conservative core flow measuremenc is required, special in-reactor calibration tests would have to be made. Such calibration tests would involve calibrating core support plate AP versus core flow during two-pump operation             i along the 100% flow control line, operating on one pump along the 100% flow I
The 0.95 factor was the result of a conservative analysis to appropriately modify the single-tap flow coefficient for reverse flow.*
control line, una calculating the correct value of C based on the core flow             t derived f rom the core support plate AP and the loop flow indicator readings, f
If a more exact, less conservative core flow measuremenc is required, special in-reactor calibration tests would have to be made. Such calibration tests would involve calibrating core support plate AP versus core flow during two-pump operation i
i j
along the 100% flow control line, operating on one pump along the 100% flow I
2.1.2     Core Flow Uncertainty Analysis The uncertainty analysis procedure used to establish the core flow uncertainty I
control line, una calculating the correct value of C based on the core flow t
for one-pump operation is essentially the same as for two-pump operation, except for some extensions. The core flow uncertainty analysis is described               j 17 Reference 2. The analysis of one-pump core flow uncertainty is summarized
derived f rom the core support plate AP and the loop flow indicator readings, f
                                                                                                      -      ?
i 2.1.2 Core Flow Uncertainty Analysis j
below.                                                                                   !
The uncertainty analysis procedure used to establish the core flow uncertainty I
l For single-loop operation, the total core ficw can be expressed as follows                         N (Figure 2-1):                                                                                       l
for one-pump operation is essentially the same as for two-pump operation, except for some extensions. The core flow uncertainty analysis is described j
                                                                                                              ,i W     "                                                                        '
17 Reference 2.
C         A ~ I i
The analysis of one-pump core flow uncertainty is summarized
E 1.here V
?
g
below.
                      =    total core flow;                                                             ; y l                                                                                                           q.
l N
I W    =    active loop flow; and 3
For single-loop operation, the total core ficw can be expressed as follows l
W   =     inactive loop (true) flow,                                                       t 7                                                                                         P>
(Figure 2-1):
,i W
C A ~ I i
' E 1.here total core flow;
; y V
=
l g
q.
active loop flow; and I
W
=
3 t
inactive loop (true) flow, W
=
7 P>
d
d
          *The expected value of the       "C" coefficient is NO.88.
*The expected value of the "C" coefficient is NO.88.
e
e
                                                                                                          ~
~
                                                    ~
~


wm                                                                                                              .h NEDO-24281 By applying the " propagation of errors" method to the above equation, the variance of the total flow uncertainty can be approximated by:
.h wm NEDO-24281 By applying the " propagation of errors" method to the above equation, the variance of the total flow uncertainty can be approximated by:
                                                                                                                    ~
a\\
2          2                    2                    a\   [2           2\
[2 2\\
Cy    " C
~
                                          +[Q1-a}l     *W j2                                 + *C rand +[(1:a}k rand W                                               1 *W sys                  A
+[Q1-a}l j2 +[(1:a}
                                                                                                  /
2 2
where oy      =  uncertainty of total core flow;                                                       _;
2
C                                                                                               _l i
*W
: c.        =  uncertainty systematic to both loops;                                                   ~l I
+ *C
sys
*W C
!          cp            =  random uncertainty of active loop only; A
" C 1
rand                                                                                                      ,
y W
I oy            =  random uncertainty of inactive loop only;                                                     i I
Arand k rand
rand a      =  uncertainty of "C" coefficient; and a =     ratio of inactive loop flow (W 7) to active loop flow (W ).g
/
:P Resulting from an uncertainty analysis, the conservative, bounding vlaues of                                 ;
sys where uncertainty of total core flow; o
s and oc are 1.6%, 2.6%, 3.5% and 2.8%, respectively.
=
owsys, cuArand, cwyrand                                                                                         6 Based on above uncertainties and a bounding value of 0.36 for                             "a", the variance     4 of the t tal flow uncertainty is approximately:
y C
                                        '                                      03                  +     21 c6'C
_l i
                          =
uncertainty systematic to both loops;
(1.6)' + (/ 11-0.36          ( .6)2+[lb.6)2-
~l c.
                                                                              \     36/   -
=
( *
I sys random uncertainty of active loop only; c
* j 4
=
                                          ,                                                                          1
p Arand I
                          =
i random uncertainty of inactive loop only; o
=
y I rand uncertainty of "C" coefficient; and a
=
ratio of inactive loop flow (W ) to active loop flow (W ).
a =
7 g
;>:P Resulting from an uncertainty analysis, the conservative, bounding vlaues of s
are 1.6%, 2.6%, 3.5% and 2.8%, respectively.
and oc owsys, cuArand, cwyrand 6
Based on above uncertainties and a bounding value of 0.36 for "a",
the variance 4
of the t tal flow uncertainty is approximately:
.6)2+[lb.6)2-21 (1.6)' + (/ 1 03 c6'
(
+
(
\\
36/
j
=
1-0.36 4
C 1
(5.0%)'
(5.0%)'
=
1 2-3
1 2-3
                                                                                                                  'l
'l


r
r
  ' W it+1Su n u .         ~. _ _. ~ .. .. m .              ..
' W it+1Su n u.
~. _ _. ~.... m.
4 NEDO-24281 k' hen the effect of 4.1% core bypass flow split uncertainty at 12% (bounding case) bypass flow fraction is added to the above total core flow uncertainty, the active coolant flow uncertainty in:
4 NEDO-24281 k' hen the effect of 4.1% core bypass flow split uncertainty at 12% (bounding case) bypass flow fraction is added to the above total core flow uncertainty, the active coolant flow uncertainty in:
2          =  ( .0%)2 + j l 0 l' h l (4.1%)' (5.0%)2                     b active                      1-0.12 coolant                  \       /                                             j i   fi t
l 0 l' h (4.1%)'
which is less than the 6% core flow uncertainty assumed in the statistical           .
(5.0%)2 b
f' analysis.                                                                                   q
(.0%)2 + j 2
                                                                                            ! 4 In su:: nary, core flow during one-pump operation is measured in a conservative     i way and its uncertainty has been conservatively evaluated.                           ,
l
=
=
1-0.12 active
\\
/
j fi coolant i
t which is less than the 6% core flow uncertainty assumed in the statistical f'
analysis.
q
! 4 In su:: nary, core flow during one-pump operation is measured in a conservative i
way and its uncertainty has been conservatively evaluated.
2.2 TIP READING UNCERTAINTY
2.2 TIP READING UNCERTAINTY
                                                                                                    /
/
To ascertain the TIP noise uncertainty for single recirculation loop operation, a test was performed at an operating Bk'R.         The test was performed at a power level 59.3% of rated with a single recirculation pump in operation (core flow         ,
To ascertain the TIP noise uncertainty for single recirculation loop operation, a test was performed at an operating Bk'R.
46.3% of rated). A rotationally syr: metric control rod pattern existed prior to the test.
The test was performed at a power level 59.3% of rated with a single recirculation pump in operation (core flow 46.3% of rated). A rotationally syr: metric control rod pattern existed prior to the test.
Five consecutive traverses were made with each of five TIP machines, giving a             i a
Five consecutive traverses were made with each of five TIP machines, giving a i
total of 25 traverses. Analysis df their data resulted in a nodal TIP noise               h of 2.85%. Use of this TIP noise value as a component of the process computer,       jf total uncertainty results in a one-sigma process computer total uncertainty             .
a total of 25 traverses. Analysis df their data resulted in a nodal TIP noise h
of 2.85%.
Use of this TIP noise value as a component of the process computer, j f total uncertainty results in a one-sigma process computer total uncertainty
(
(
value for single-loop operation of 9.1% for relcad cores.                                 >
value for single-loop operation of 9.1% for relcad cores.
h 4
h 4
t i
ti n
n 2-4
2-4


I
I liED0-24281 l
                    '                    liED0-24281                                           l l I l
I l
                                                                                                \
\\
CORE b
CORE b
w, WC WA W
WC w,
WA W
WC
WC
* TOTAL CORE FLOW WA = ACTIVE LOOP FLCW W) = INACTIVE LOOP FLCW ion Flows Illustration of Single Recirculation Loop Operat Figure 2-1.
* TOTAL CORE FLOW WA = ACTIVE LOOP FLCW
2-5/2-6 I
= INACTIVE LOOP FLCW W) ion Flows Illustration of Single Recirculation Loop Operat Figure 2-1.
I 2-5/2-6


E
E
{
{
NED0-24281                                               >
NED0-24281 t
t
[
[ .
3.
: 3. MCPR OPERATING LIMIT I
MCPR OPERATING LIMIT I
I i
I 3.1 CORE-k'IDE TRANSIENTS i
3.1 CORE-k'IDE TRANSIENTS                                                                           i hich Operation with one recirculation loop results in a maximum Therefore,              power output w is 20 to 30% below that which is attainable for two-pump operation.     l     peration the consequences of abnormal operational transients from one- loop           oop oopera-will be considerably less severe than those analyzed from a two-flow decrease and cold water increase tran-                     '
i hich Operation with one recirculation loop results in a maximum power output w Therefore, is 20 to 30% below that which is attainable for two-pump operation.
tional mode. For pressurization,                                               hermal and sients, previously transmitted Reload /FSAR results bound both the t overpressere consequences of one-loop operation.
l peration the consequences of abnormal operational transients from one-oop o loop opera-will be considerably less severe than those analyzed from a two-flow decrease and cold water increase tran-For pressurization, hermal and tional mode.
(tur-Figure 3-1 shows the consequencesAsofcan              a typical   pressurization transient be seen, the consequences of                 f bine trip) as a function of power level.                                     d reduction one-loop operation are considerably less because of the associate in operating power level.
sients, previously transmitted Reload /FSAR results bound both the t overpressere consequences of one-loop operation.
full The consequences from flow decrease transients are also bounded by the                                 ,
(tur-Figure 3-1 shows the consequences of a typical pressurization transient As can be seen, the consequences of f
A single pump trip from one-loop operation is less severe power analysis.                                                     d initial power than a two-pump trip from full power because of the reduce level.
bine trip) as a function of power level.
Cold water increase transients can result from either recirculation pump                               l or introduction of colder water into the reactor vessel by speedup or restart, The K g factors are derived assuming events such a" loss of feeduater heater.
d reduction one-loop operation are considerably less because of the associate in operating power level.
that both recirculation loops increase speed to the maximum permitted by the M-C set scoop tube position. This condition produce: the maximum possible ii     d from less power increase and, hence, maximum ACPR for transients in t ate                                     -
full The consequences from flow decrease transients are also bounded by the A single pump trip from one-loop operation is less severe power analysis.
When operating with only one recirculation loop, than rated power and flow.                                     d speed on only one the flew and power increase asscciated with the increase associated with both pumps increasing speed; M-C set will be less than that therefore, the K g factors derived with the two-pump assumption are conserva-tive for single-loop operation. Inadvertent restart of the idle recirculation pump would result    in a neutron flux transient which would exceed the flow The resulting scram is expected to be less severe than the reference scrat.                                     The latter event (loss of rated power / flow case documented in the FSAR.
d initial power than a two-pump trip from full power because of the reduce level.
1 3-1                                                     )
Cold water increase transients can result from either recirculation pump l
or introduction of colder water into the reactor vessel by speedup or restart, factors are derived assuming The K events such a" loss of feeduater heater.
g both recirculation loops increase speed to the maximum permitted by the scoop tube position. This condition produce: the maximum possible that M-C set ii d from less power increase and, hence, maximum ACPR for transients in t ate When operating with only one recirculation loop, than rated power and flow.
d speed on only one the flew and power increase asscciated with the increase associated with both pumps increasing speed; M-C set will be less than that factors derived with the two-pump assumption are conserva-therefore, the K Inadvertent restart of the idle recirculation g
tive for single-loop operation.
in a neutron flux transient which would exceed the flow pump would result The resulting scram is expected to be less severe than the reference scrat.
The latter event (loss of rated power / flow case documented in the FSAR.
1 3-1
)
L,
L,


                                                                                                        ~
~
  $ : .s2 s. .T 2     .l . ..:..** : . . ... _ a. ..
$ :.s2 s..T 2
* I 4
.l a.
SEDO-24281 feedwater heating) is generally the most severe cold water increase event with respect to increase in core power. This event is caused by positive reactivity insertion from core flow inlet subcooling; therefore, the event is primarily I
I SEDO-24281 4
dependent on the initial power level. The higher the initial power level, the                 1 greater the CPR change during the transient. Since the initial power level during one-pump operation will be significantly lower, the one-pump cold water increase case is conservatively bounded by the full power (two-pump)             i       I
feedwater heating) is generally the most severe cold water increase event with respect to increase in core power. This event is caused by positive reactivity insertion from core flow inlet subcooling; therefore, the event is primarily I
                                                                                                      <,l analysis.
dependent on the initial power level. The higher the initial power level, the 1
ll l Jd From the above discussions, it can be concluded that the transient consequence         lE from one-loop operation is bounded by previously submitted full power analysis.
greater the CPR change during the transient. Since the initial power level during one-pump operation will be significantly lower, the one-pump cold water increase case is conservatively bounded by the full power (two-pump)
3.2   ROD WITHDRAWAL ERROR The rod withdrawal error at rated power is given in the FSAR for the initial         ,
I i
core and in cycle-dependent reload supplemental submittals. These analyses         l' are performed to demonstrate that, even if the operator ignores all instrument     l indications and the alarm which could occur during the course of the transient, the rod block system will stop rod withdrawal at a minimum critical power ratio (MCPR) which is higher than the fuel cladding integrity safety limit. Correc-tion of r.he rod block equation (see the following) and lower power assures that   ;        .
<,l analysis.
                                                                                                      .,=
,l J l l d From the above discussions, it can be concluded that the transient consequence lE from one-loop operation is bounded by previously submitted full power analysis.
3.2 ROD WITHDRAWAL ERROR The rod withdrawal error at rated power is given in the FSAR for the initial core and in cycle-dependent reload supplemental submittals. These analyses l'
are performed to demonstrate that, even if the operator ignores all instrument l
indications and the alarm which could occur during the course of the transient, the rod block system will stop rod withdrawal at a minimum critical power ratio (MCPR) which is higher than the fuel cladding integrity safety limit. Correc-tion of r.he rod block equation (see the following) and lower power assures that
.,=
the MCPR safety limit is not violated.
the MCPR safety limit is not violated.
1
1' ;
[
[
One-pump operation results in backflow through the inactive bank of jet pumps while the flow is being supplied into the lower plenum from the active bank of     j l
One-pump operation results in backflow through the inactive bank of jet pumps while the flow is being supplied into the lower plenum from the active bank of j
jet piutp s . Because of the backflow through the inactive jet pumps, the present i
l Because of the backflow through the inactive jet pumps, the present i
t rod block equation was conse natively modified for use during one-pump operation I
jet piutp s.
                                                                                                          ~
t rod block equation was conse natively modified for use during one-pump operation I
because the direct active-loop flow measurement may not indicate actual flow     l above about 35% drive flow without correction.
~
A precedure has been established for correcting the rod block equation to account for the discrepancy between actual flow and indicated flow in the active loep. This preserves the original relationship between rod block and actual effective drive flow when operating with a single loop.
because the direct active-loop flow measurement may not indicate actual flow l
above about 35% drive flow without correction.
A precedure has been established for correcting the rod block equation to for the discrepancy between actual flow and indicated flow in the account active loep. This preserves the original relationship between rod block and actual effective drive flow when operating with a single loop.
3-2
3-2


NEDO-24281 The two-pump rod block equation is:                                                                                                   i RB    =    mW +   RB     - m(100) 100                               _.
NEDO-24281 The two-pump rod block equation is:
The one-pump equation becomes:
i mW +
                                    =    mW + R2 100                                    ~ 0 RB
RB
                                                          ' *(
- m(100)
where aW    =    difference, determined by utility, between two-loop and single-loop effective drive flow at the same core flow; RB    =    power at rod blbck in %;
RB
m =     flow reference slope for the rod block monitor (RBM);
=
i W  =    drive flow in % of rated; and                                                                               A j?
100 The one-pump equation becomes:
RB        -    t p level rod block at 100% flow.
100 ' *(
100                                                                                                                       .
~ 0 mW + R2 RB
i If the rod block setpoint (RB100) is changed, the equation must be recalculated
=
                                                                                                                                                  ^l; using the new value.                                                                                                                 3 i
where difference, determined by utility, between two-loop and single-aW
The APRM trip settings are            flew biased in the same manner as the rod block                         -                      .
=
monitor trip setting. Therefore, the APRM rod block and scram trip settings are subject to the same procedural changes as the rod block monitor trip set-ting discussed above.
loop effective drive flow at the same core flow; power at rod blbck in %;
RB
=
flow reference slope for the rod block monitor (RBM);
m =
i drive flow in % of rated; and A
W
=
j?
t p level rod block at 100% flow.
RB 100 i
If the rod block setpoint (RB100) is changed, the equation must be recalculated
^l; using the new value.
3 i
flew biased in the same manner as the rod block The APRM trip settings are Therefore, the APRM rod block and scram trip settings monitor trip setting.
to the same procedural changes as the rod block monitor trip set-are subject ting discussed above.
1 3-3
1 3-3
          - - -            -                              - _ - - _ - - - - - - - -        ---e----- mw- w- - -w--w--- w,- -  - - --e v-
---e-----
mw-w-
-w--w---
w,-
--e v-


k % 'aET, X.~nw t c~ v 7. c m a a n .sa .u s u a . .. . ... , _ _ _ . _ _
k % 'aET, X.~nw t c~ v 7. c m a a n.sa.u s u a......., _ _ _. _ _
NEDO-24281 3.3 OPERATING MCPR LIMIT                                                             i For single-loop operation, the rated condition steady-state MCPR limit is increased by 0.01 to account for the increase in the fuel cladding integrity                             l l
NEDO-24281 3.3 OPERATING MCPR LIMIT i
safety limit bection 2) . At lower flows, the steady-state MCPR operating             i limit is conservatively established by multiplying the rated flow steady-state         i               p limit by the Kg factor. This ensures that the 99.9% statistical limit require-         .
For single-loop operation, the rated condition steady-state MCPR limit is increased by 0.01 to account for the increase in the fuel cladding integrity safety limit bection 2). At lower flows, the steady-state MCPR operating i
ment  is always satisfied for any postulated abnormal operational transient.
limit is conservatively established by multiplying the rated flow steady-state i
L l
p limit by the K factor. This ensures that the 99.9% statistical limit require-g is always satisfied for any postulated abnormal operational transient.
1 I
ment L
i
l 1
                                                                                                  ,        I L
I i
I L
r I
r I
l I
l I
Line 307: Line 424:
l I
l I
l l
l l
3-4                                                 ,
3-4 I
I l
l l
l
\\
\       _.                                                                        _ _ _ .
 
* i
i NED0-24281 i
    .                                                    NED0-24281 i
1160 t
1160                                                                                                           !
lY ii a
t           !
aco l
lY ii a       ,
E 4
                                                                                                -            aco
2 uso -
                                                                                                                  <      l E       4 uso -                                                                                                         2 5         .
5 e
e o
o I
I E
E U
U 11oo    -
i' 11oo 2
i''
W sooj
2 W
~}.io.o a-5 w
_          sooj a
E 5
      ~}.io.o w
5 i
5 E
N i
5                                                                                                           5            i N
y w
w                                                                                                           y          i 2                                                                                                           -
2 d
d a 'oso
f a 'oso s
                                                                                                                    !          f s4 5                                                                                                                       l E
l 5
sw                                                                                                                        f t
4 E
G                                                                                                                       ,
f s
j 1 4o                                                                                                                   ,
t w
        .5                                                                                                                       t t
G j 1 4o
to2a                                                                                                             ,
.5 t
1000 l
t to2a 1000 l
900-                                                   c RANGE OF EXPECTED -
900-c RANGE OF EXPECTED -
M AxiquM ONE LOOP POWER OPER ATION l       I I           I                                   1;ro              14o eso                                          so      ao      too o           20         .o POWER LEVEL (% NUCLEAR SOILER RATEDI 1
M AxiquM ONE LOOP POWER OPER ATION l
I I
I 14o o
20
.o so ao too 1;ro eso POWER LEVEL (% NUCLEAR SOILER RATEDI 1
Main Turbine Trip with Bypass Manual Flow Control Figure 3-1.
Main Turbine Trip with Bypass Manual Flow Control Figure 3-1.
3-5/3-6 e
3-5/3-6 e
                                                                                                -=mwyy_,_%__
^ - ' ~ ' - ' - - - - - _ _ _ _ _
-=mwyy_,_%__


NEDO-24281
NEDO-24281 4.
: 4. STABILITY ANALYSIS The least stable power / flow condition attainable under   for ratednormal    conditions power and occurs at natural circulation with the control rods set                                             j flow.
STABILITY ANALYSIS The least stable power / flow condition attainable under normal conditions for rated power and occurs at natural circulation with the control rods set j
This condition may be reached following the trip of both recirculation pumps.
This condition may be reached following the trip of both recirculation As shown in Figure 4-1, operation along the minimum forced recircula-flow.
As shown in Figure 4-1, operation along the minimum               forced recircula-ble than operating 2
2 ble than operating pumps.
tion line with one pump running at minimum speed is more sta is less stable than operating with both with natural circulation flow only, but
tion line with one pump running at minimum speed is more sta is less stable than operating with both with natural circulation flow only, but
                                                                                                          ?
?
pumps operating at minimum speed.
pumps operating at minimum speed.
y l
l y
1 During single-loop operation, the flow control should beflow    in master     manua ,
During single-loop operation, the flow control should be in master manua,
control system                 :
1:
since control oscillations might occur in the recirculation under automatic flow control conditions.                                                             't
flow control system since control oscillations might occur in the recirculation under automatic flow control conditions.
                                                                                                          ?
't
?
I l
I l
9
9
                                                                                                                ,e a
,e a
9 m
9 m
4-1 l
4-1 AS l
AS l
l l
l


J.-,-
J.-,-
NEDO-24281 1.2 ULTIMATE STASILITY LIMIT 1.0     ------ - = = =                                           a-- -    a-== -            - ,-                ]
NEDO-24281 1.2 ULTIMATE STASILITY LIMIT 1.0 ------ - = = =
                                                                        - - -- SINGLE LOOP. PUMP MINIMUM SPEED
a--
                                                                          -            SOTH LOOPS, PUMPS MINIMUM SPEED c.s     -
a-==
I
]
        ~
- - -- SINGLE LOOP. PUMP MINIMUM SPEED SOTH LOOPS, PUMPS MINIMUM SPEED c.s I
O                                                                                                                 !
~O A
A                                                                                                                   .
.5 9
        .5                                                                                                                 !
e Q
9                                                                                                                  e Q     o.6     -
o.6
{
{
z
z
        ,o                                                   NATURAL Q                                                    CIRCULATION      /     RATED FLOW CONTROL LINE d
,o NATURAL
LINE          /                                                         -
/
V                                                   , .
RATED FLOW CONTROL LINE d
a4      -                                          /                                                         ' i HIGHEST POWER ATTAINAS LE         t     ?<
Q CIRCULATION
                                                            /                                           FOR SINGLE                 h
/
                                                          //                                           LOOP OPER ATION J
LINE V
l o:       -
/
: l. bi
' i a4 HIGHEST POWER ATTAINAS LE t
                                                                                                                              . 1 i
?<
i    f, l
/
l                                                                                                                                { '.
FOR SINGLE h
I                           f                 I                 I                 '
//
o o                   ao                           40               to                 80           100 j I POWER (%)
LOOP OPER ATION l
* t
J l b o:
                                                                                                                                  .l Figure 4-1.     Decay Ratio Versus Power Curve for Two-Loop and l 'j Single-Loop Operation                                                                 -d 4-2                                                 ,
. i 1
Id
i i
f, l
{ '.
l I
f I
I o o ao 40 to 80 100 j
I POWER (%)
.l t
Figure 4-1.
Decay Ratio Versus Power Curve for Two-Loop and l 'j Single-Loop Operation
- d 4-2 Id


m w.                     - - -
m w.
Mr-h NEDO-24281 l
Mr-h NEDO-24281 l
l t
l t
t
t 5.
: 5. ACCIDENT ANALYSES                               l 6
ACCIDENT ANALYSES l
The broad spectrum of postulated accidents is covered by six categories of d2aign basis events. These events are the loss-of-coolant, recirculation pump caizure, control rod drop, main steamline break, refueling, and fuel assembly l
6 The broad spectrum of postulated accidents is covered by six categories of d2aign basis events. These events are the loss-of-coolant, recirculation pump caizure, control rod drop, main steamline break, refueling, and fuel assembly l
lording accidents. The analytical results for the loss-of-coolant and recir-i culation pump seizure accidents with one recirculation pump operating are             Fa 5
lording accidents. The analytical results for the loss-of-coolant and recir-i culation pump seizure accidents with one recirculation pump operating are Fa 5
given below. The results of the two-loop analysis for the last four events             y are conservatively applicable for one-pump operation.
given below. The results of the two-loop analysis for the last four events y
5.1   LOSS-OF-COOLANT ACCIDENT ANALYSIS                                                 I; A single-loop operation analysis utilizing the models and assumptions documented         (f l
are conservatively applicable for one-pump operation.
4I in Ref erence 3 was performed for the FitzPatrick Nuclear Power Plant. Using             l ir
5.1 LOSS-OF-COOLANT ACCIDENT ANALYSIS I;
                                                                                                  ')
(f l
this method, SAFE /REFLOOD computer code runs were made for a full spectrum of break sizes for the suction and discharge side breaks. The reflooding time for the single-loop analysis is similar to the two-loop analysis, and the Maximum Average Planar Linear Heat Generation Rate (MAPLHGR) curves currently applied were modified by derived reduction factors for use during one recirculation pump           [i";
A single-loop operation analysis utilizing the models and assumptions documented 4 I in Ref erence 3 was performed for the FitzPatrick Nuclear Power Plant.
ope rat ion.                                                                               V t.
Using l ir
5.1.1   Break Spectrum Analysis                                                             'r
')
                                                                                                  \
this method, SAFE /REFLOOD computer code runs were made for a full spectrum of break sizes for the suction and discharge side breaks. The reflooding time for the single-loop analysis is similar to the two-loop analysis, and the Maximum Average Planar Linear Heat Generation Rate (MAPLHGR) curves currently applied were modified by derived reduction factors for use during one recirculation pump
A break spectrum analysis was performed using the SAFE /REFLOOD cceputer codes               fi f,4 ar.d the assumptions giv1n in Section II.A.7.2.2. of Reference 3.                              .
[i";
ope rat ion.
V t.
5.1.1 Break Spectrum Analysis
'r
\\
fi A break spectrum analysis was performed using the SAFE /REFLOOD cceputer codes f,4 ar.d the assumptions giv1n in Section II.A.7.2.2. of Reference 3.
m b
m b
The discharge break spectrum and the suction break spectrum reflooding times for             k one recirculation loop operation are compared to the standard previously per-t ormed two-loop operation in Figures 5-1 and 5-3. The uncovered tines (reflood time minus recovery time) for each break spectrum are compared in                     }
The discharge break spectrum and the suction break spectrum reflooding times for k
Figures 5-2 and 5-4                                                                             !
recirculation loop operation are compared to the standard previously per-one t ormed two-loop operation in Figures 5-1 and 5-3.
For the FitzPatrick Nuclear Power Plant, the reflooding time for the limiting break in standard two-loop operation is 247 seconds, occurring at 80% of the Desien Basis Accident (DBA) discharge break. The boiline transition time ranges to 10.i seconds for the three fuel types. For the sinele-loop analv+1s,           B from 9                                                                                        i 5-1                                               i
The uncovered tines (reflood time minus recovery time) for each break spectrum are compared in
}
Figures 5-2 and 5-4 For the FitzPatrick Nuclear Power Plant, the reflooding time for the limiting break in standard two-loop operation is 247 seconds, occurring at 80% of the Desien Basis Accident (DBA) discharge break. The boiline transition time ranges from 9 to 10.i seconds for the three fuel types.
For the sinele-loop analv+1s, B
i 5-1 i


f m .__    _
..... i,-:jf f m.__
                    . _ ,  . _ _ . _ - - m    . . . . . i ,-:jf NEDO-24281 the most limiting break also occurs at the 80% DBA discharge break, and the reflooding time is 247 seconds. The uncovered time at the most limiting break is 213 seconds for the two-loop analysis and 214 seconds for the single-loop analysis.
m NEDO-24281 the most limiting break also occurs at the 80% DBA discharge break, and the reflooding time is 247 seconds. The uncovered time at the most limiting break is 213 seconds for the two-loop analysis and 214 seconds for the single-loop analysis.
5.1.2   Single-Loop MAPLHGR Determination The small difference in uncovered time for the limiting break size would result in a very small change in the calculated peak cladd ag temperature. Therefore,           ,
5.1.2 Single-Loop MAPLHGR Determination The small difference in uncovered time for the limiting break size would result in a very small change in the calculated peak cladd ag temperature. Therefore, as noted in Reference 3, the one-and two-loop SAFE /REFLOOD results can be con-sidered similar and the generic alternative procedure described in Section II.A.7.4 of this reference was used to calculate the MAPLHGR reduction factors for single-loop operation.
as noted in Reference 3, the one- and two-loop SAFE /REFLOOD results can be con-sidered similar and the generic alternative procedure described in Section II.A.7.4 of this reference was used to calculate the MAPLHGR reduction factors for single-loop operation.                                                                                   y.
y.
k MAPLHGR reduction factors were determined for the cases given in Table 5-1.
k MAPLHGR reduction factors were determined for the cases given in Table 5-1.
The most limiting reduction factors for each fuel type is shown in Table 5-2.
The most limiting reduction factors for each fuel type is shown in Table 5-2.
t One-loop operation MAPLHGR values arc derived by multiplying the current two-loop operation MAPLHGR values by the reduction factor for that fuel type.                .
t One-loop operation MAPLHGR values arc derived by multiplying the current two-loop operation MAPLHGR values by the reduction factor for that fuel type.
As discussed in Reference 3, single recirculation loop MAPLHGR values are               '
As discussed in Reference 3, single recirculation loop MAPLHGR values are f
f conservative when esiculated in this manner.                                            .
conservative when esiculated in this manner.
5.1.3   Small Break Peak Cladding Temperature f
5.1.3 Small Break Peak Cladding Temperature f
Section II.A.7.4.f.2 of Reference 3 discusses the small sensitivity of the i                                                                       r y
r Section II.A.7.4.f.2 of Reference 3 discusses the small sensitivity of the i
calculated peak clad temperature (PCT) to the assumptions used in the one-pump operation analysis and the duraticn of nucleate boiling. Since the slight                 I increase (%50*F) in PCT is overwhelmingly offset by the decreased MAPLHCR (equivalent to 300* to 500*F *. PCT) for one-pu=p operation, the calculated PCT                   ,
y calculated peak clad temperature (PCT) to the assumptions used in the one-pump I
values for small breaks will be well below the 2200*F 10CFR50.46 cladding temperature limit.
operation analysis and the duraticn of nucleate boiling.
Since the slight increase (%50*F) in PCT is overwhelmingly offset by the decreased MAPLHCR (equivalent to 300* to 500*F *. PCT) for one-pu=p operation, the calculated PCT values for small breaks will be well below the 2200*F 10CFR50.46 cladding temperature limit.
F L
F L
5.2 ONE-PUMP SEIZURE ACCIDENT j
5.2 ONE-PUMP SEIZURE ACCIDENT j
The one-pump seizure accident is a relatively mild event during two-                               '
The one-pump seizure accident is a relatively mild event during two-recirculation-pump operation, as documented in References 1 and 2.
recirculation-pump operation, as documented in References 1 and 2. Similar analyses were performed to determine the impact this accident would have on                 '}
Similar analyses were performed to determine the impact this accident would have on
'}
l C.1
l C.1


    .                                                EEDO-26281                                     (
EEDO-26281
(
k:
k:
0 one-recirculation-pump operation. These analyses were performed with the t{
0 t {
models documented in Reference 1 for a large core BWR/4 plant (Reference 4).           !\i l to The analyses were initialized from steady-state operation at the following initial conditions, with the added condition of one inactive recirculttion loop. Two sets of initial conditions were assumed:                                     g l\'
one-recirculation-pump operation. These analyses were performed with the models documented in Reference 1 for a large core BWR/4 plant (Reference 4).
E 1
!\\i l to The analyses were initialized from steady-state operation at the following initial conditions, with the added condition of one inactive recirculttion loop. Two sets of initial conditions were assumed:
                                                                                                        ,l (1) Thermal Power = 75% and core flow = 58%                                         >
g l\\'
E 1,l (1) Thermal Power = 75% and core flow = 58%
l
l
                                                                                                        'i I                         (2) Thermal Power = 82% and core flow = 56%                                 ld 2          These conditions were chosen because they represent reasonable upper limits of             lh  5
'i I
: h.           ,
(2) Thermal Power = 82% and core flow = 56%
q single-loop operation within existing MAPLHGR and MCPR limits at the same maximum pump speed. Pump seizure was simulated by setting the single operating                 4 i           pump speed to zero instantaneously.                                                                 )
ld lh 5
U p
These conditions were chosen because they represent reasonable upper limits of 2
The anticipated sequence of events following a recirculation pump seizure which occurs during plant operation with the alternate recirculation loop out of service is as follows:
h.
(1) The recirculation loop flow in the loop in which the pump seizure             ;
single-loop operation within existing MAPLHGR and MCPR limits at the same q
occurs dreps instantaneously to zero.
maximum pump speed. Pump seizure was simulated by setting the single operating 4
(2) Core volds increase which results in a negative reactivity inser-                   ,
i pump speed to zero instantaneously.
:                              tion and a sharp decrease in neutron flux.                                         ,
)Up The anticipated sequence of events following a recirculation pump seizure which occurs during plant operation with the alternate recirculation loop out of service is as follows:
                                                                                                            )?
(1) The recirculation loop flow in the loop in which the pump seizure occurs dreps instantaneously to zero.
i' (3) Heat flux drops more slowly because of the fuel time constant.                 ]
(2) Core volds increase which results in a negative reactivity inser-tion and a sharp decrease in neutron flux.
                                                                                                        .I (4) Neutron flux, heat flux, reactor water level, stean flow, and feed-       'j*i r
) ?
j                              water flow all exhibit transient behaviors. However, it is not           8 f
i' (3) Heat flux drops more slowly because of the fuel time constant.
anticipated that the increase in water level will cause a turbine trip and result in scram.
]
1 It is expected that the transient will terminate at a condition of natural circulation and reactor operation will continue. There will also be a small I
.Ii'j*
(4) Neutron flux, heat flux, reactor water level, stean flow, and feed-r j
water flow all exhibit transient behaviors. However, it is not 8
f anticipated that the increase in water level will cause a turbine trip and result in scram.
It is expected that the transient will terminate at a condition of natural circulation and reactor operation will continue. There will also be a small I
decrease in system pressure.
decrease in system pressure.
!                                                          ,->                                              J
J


NEDO-24281 The minimum CPR for the pump seizure accident for the large core BWR/4 plant was determined to be greater than the fuel cladding integrity safety limit; therefore, no fuel failures were postulated to occur as a result of this analyzed event.
NEDO-24281 The minimum CPR for the pump seizure accident for the large core BWR/4 plant was determined to be greater than the fuel cladding integrity safety limit; therefore, no fuel failures were postulated to occur as a result of this analyzed event.
i l
i l
These results are applicable to the FitzPatrick Nuclear Power Plant.                             'I,4 14 li 1,'
These results are applicable to the FitzPatrick Nuclear Power Plant.
'I,4 14 li1,'
J.
J.
0 r
0 r
i
i
                                                                                                  ?
?
ll
ll
                                                                                                  ,i i-I i
,i i-I i
k
k


NED0-24281                                       r l
NED0-24281 r
i-               .
l i-Table 5-1 MAPLHGR MULTIPLIER CASES t.
Table 5-1 MAPLHGR MULTIPLIER CASES                                                     _
l Fuel Type Cases Calculated i
t.
7x7 80% DBA Discharge Break *
l                   -
}j p,:
Fuel Type                                                                           Cases Calculated         i 7x7                                                                         80% DBA Discharge Break *
85% DBA Discharge Break p
                                                                                                                                            }j p ,:
100% DBA Suction Break I'
85% DBA Discharge Break           p               -
8x8 80% DBA Discharge Break
100% DBA Suction Break             I' 8x8                                                                         80% DBA Discharge Break
* K
* K   -
?
                                                                                                                                                ?
1 85% DBA Discharge Break I,i 9
1 85% DBA Discharge Break           I ,i       9 Is 100% DBA Suction Break                             j 8x8R                                                                       80% DBA Discharge Break *           [,.
Is 100% DBA Suction Break j
8x8R 80% DBA Discharge Break *
[,.
4 3
4 3
85% DBA Discharge Break             (           -
85% DBA Discharge Break
100% DBA Suction Break               f;f 4
(
100% DBA Suction Break f;f 4
l
l
              *Most limiting break for MAPLHGR reduction factors.                                                                 k
*Most limiting break for MAPLHGR reduction factors.
                                                                                                                                      'l     1
k
'l 1
(?
(?
i Table 5-2 l
Table 5-2 i
l                                                      LIMITING MAPLHGR REDUCTION FACTORS                                             p j                                                                                                                                      k ,.,
l l
l Fuel Type                                                       Reduction Factors f-7x7                                                                 0.84                                       l 8x8                                                                 0.85 8x8R                                                               0.84                                         ,
LIMITING MAPLHGR REDUCTION FACTORS p
M e
k,
A I.$
j l
f Fuel Type Reduction Factors 7x7 0.84 l
8x8 0.85 8x8R 0.84 M
e A
I.$


J~d.'.                                     _ . . _ _ _ _ . ' ' '''
J~d.'.
MEDO-26281 1
MEDO-26281 1
3
3 3
                                                                                                                                                    -  3
=
                                                =                                                                                                     -
8 O
                                            . 8 O   -f O w
-f O w s!
B
[
[
s!                                                                                                    -
i o
B i
E d
'                                                                                                                                                                    o       ,
e i
E         d-e
p l
* p           .
{
l                                                i                                                                                                                          {
6
l 6         ?O         -
?
i m          l w          !
l O
e cc:
l i
e           8         1
mw e
                                                                                                                                                        -          u         e i
cc:
I "u
e 8
Q l                                                                                                                                                                 Q-V3
1 e
                                                                                                                                                /
u i
                                                                                                                                                        !a O ie a       L
"u I
* O     M                     a
Q l
                                                                                                                                                          $.      U
Q-V3
                                                                                                                                                          <      2 O   W                           -
!a i
                                                                                                              ,-                                  ~
/
m   g   j                      i 2       g r
O e
                                                                                                                                                          <    w
a L
                                                                                                                                                          $    C                   ,
O M
                                                                                                                                                          =   a                     .
a U
                                                                                                                                                  -=           3                   i.
2 O
W g
j
~
m i
g 2
r w
C
=
a
-=
3 i.
w
w
[                                                                                                                                                               .
[
u
%u
                                                                                                                                                              **9                     4 e      w                    .
**9 4
l
l e
                                                                                                                                                                  .      4 i
w 4
(                                                                                                                                                             -
i
I s                                                                                                                                 n                   ..,
(
                            \                                                                                                                   -
I s
n
\\
8 I
8 I
i w
i w
w                   z
w z
                          /     {                                                                                                                                         i           =
/
{
i
=
S s
S s
N N
N N I
I                                   I             I     I           I              o                 ,
I I
s           s                e           s                                   s             e               s-              .
I I
a           a                 n           a                                 ~               n     .s.                        -
o s
P**) 3 W11 DNICOOl d 3 to i
s e
s s
e
.s.
s a
a n
a
~
n P**) 3 W11 DNICOOl d 3 to i
i I
i I
                                                                                                                                                                        . e ed *.
. e ed *.


M
M NEDO-24281 I
  .                                  NEDO-24281 I
?
                                                                                  ?
?
                                                                  ?
?
                                                                  ?
.s 81 a
                .s 81                                         -      a 8d
~
                                                                  ~
8d j'.
E 5i                                                       i:     j'.
E 5i i:
r; I                                       _      a     ?
r;
                                                                    -      g I
?
l                                                             8 e
I a
o
I g
                                                            ~
l 8
C      E' b
e o
8 2 &        i l
E' C
E8   x a ?         !
~
e -          i E
b 8
r e         !
2 i
i                                                                       e
l E8 a
                                                                        =
?
a a            ,
x i
'                                                                          3           ,
e E
I f4          I.
r e
                                                                                      }.
e a
{                                                           r;         4 i                                                           3         h R    Cs.
i
=
a l
3 f
I.
}.
4 I
{
4 r;
h i
R 3
Cs.
N A
N A
N                                       -    8       .,
N 8
5 N
5 N*
                        )                                                   h.
)
                      /
h.
                  /                                             -
/
S N
/
s's             %
S N s's N
N I         i         l         l g
I i
E R_
l l
k          k        8 I*) 36111 G3H3 AODNQ 1V101 5-7
k k
8 E
R_
g I*) 36111 G3H3 AODNQ 1V101 5-7


NED0-24281 8
NED0-24281 8
                                                                                      ~
~
1
1
                                                    \                                             i l
\\
I L                       _    g A                        l L
l i
m 8 8d                          1
I L
                              %e                             i 35                                                             .
g l
A 8
L m8d 1
%e i
35
{
I g
j 8
I
I
{
\\
g 8      j I
\\
                                                                \
y M
                                                                \                            y M
a g
a     g
\\
                                                                  \                         t
t
                                                                    \                       35 0
\\
35 0
O g
O g
8;   i
8; i
                                                                      \                   35 1 2
\\
                                                                        \                    a
35
                                                                        \         -
\\
8 s
1 2
a
\\
s 8
3
3
                                                                          )                   0 e
)
U l               c I
0 e
U l
c I
I v~.
I v~.
                                                                          /                   ;        '
/
i l             -
l 8
8 5
i 5
1 I               1                 1               g E
1 I
E 6        $  3              $
1 1
(m) 3MI LNt0001338 s'
g 6
                                              =.>                                                   ,,
3 E
E (m) 3MI LNt0001338 s'
=.>


NEDO-24281 8
NEDO-24281 8
e         *
e
                                                      \
\\
I I
I I
                                                                                      ~
l 8
8 l
~
                    .8                                     L 8d                                   1 NN
.8 L
                                                            \                       -
8d 1
a     8 I
NN
i
\\
                                                              \                                p g                             .g o
a 8
                                                                \                             a:
I
\\
p i
g
.g o
\\
o
o
                                                                \                   -
\\
R     9             i' j                         -
a:
R 9
i j
E 8
E 8
                                                                  \                       &
\\
O O
O O
as;
\\
                                                                        \
as; c
                                                                                            $  c
\\
                                                                        \s 03e 1
03 s
a 5 '
1 e
                                                                            \
a 5
m           >;
\\
a   ;            .;
m a
a c.,
a c.,
                                                                                                              -:t l
t l
l 5
l 5
k               ;
k, 2
2
/'
                                                                              /'             >
/
                                                                            /                 s
s
                                                                        /                   5 k
/
i j                                       ,
5 i
j                 -
k j
a                  ~
a j
l       i               I                       I           g 3         $      $                $                      S           E pas) 3Wil DNICOO7 338 e a.35.v;-
~
l i
I I
g 3
S E
pas) 3Wil DNICOO7 338 e a.35.v;-


  ,i,       i 1.
,i, i
1.
i z
i z
c z1'ef $' wc~
z1'ef $' wc~
T 0
c T
0 1
00 1
                            /
/,
0
0
                                /
/
1 9
1 9
p                                                                   s e
p sem i
m i        I 0           T f
I T
0 f
i 8
i 8
d e              _
de r
r
/
                                      /                                                                 e v
ev
o c
/
                                        /                                                               1 U
oc 1
                                                                                                                  ~-
Y U
Y                                                              m          ~
~-
0           u i
~
7 r         "
m 0
7 t           *-
u i
c           Q
7 r
                                            /                                                      )     e A     p B   S           *
7 t
                                              /                                                  D F   k           M"M O     a
/
                                                /                                                  %    e           %
c Q
5
e
(    r            $
)
e       0       A   B 6
M"M A
                                                  /                                                E l
p
f A
/
n o
B S
                                                        /                                           K   i t
D F
N  -
k
A    c E                   "
/
O a
e
(
r 5
/
e 0
A B
6 E
l n
N fA o
/
i K
t A
c
[
E R
u B
S
[
[
R    u
"=
* B  S                "
k c
[                                          k c
/
                                                                                                                          "=
i 5 r
                                                                /                    i 5 0           i r
g 7
0 i
t g
t g
g 7
/
                                                                    //                                   P i
g7 a
a z
g P
t g7g
t
                                                                                                                            ^4 y
^4 z
                                                                        /                                 F                              ,
/
P
y i
                                                                          /                                 .
/
O                                                                                  4 P    O                                                                e 0
L-                                                                      4            -                              .
O                                                                                        5 O    E                                                                                                                F L. L                                                                                    e O GN W    I r
u W
T    S                                                                                    g                        '
i                            '    .
F
F
                          -                                                                                                     ew
/
_                                                                                        i 0
P O
.                                                                                              3                               ..
4 P
O e
04 O
L-5 F
O E
W L.
L e
O G r
N W
I u
T S
g i
F ew 0
i 3
w
w
                                                                            -                  0                                         ~
~
                                            ~                  -                              2
0
                            -                                  0           0 0                   6           5 0               0              1 9             8
~
                                      $I>G Owc ?$2a J.           O.-
2 0
YcsV                                                                                   '
0 5
1 !                                          ,'    ;'!                        :I                       .
0 0
6 1
0 8
9
$I>G Owc ?$2a J.
O.-
YcsV 1
:I


M lu. -
M lu. -
NEDO-24281
NEDO-24281 6.
: 6. REFERENCES                                   .
REFERENCES
: 1. " Generic Reload Fuel Application, General Electric Company", August 1979 ,
" Generic Reload Fuel Application, General Electric Company", August 1979 1.
(NEDE-240ll-P-A).
(NEDE-240ll-P-A).
Data, Correlation   l.l
Data, Correlation l.l
: 2. " General Electric BWR Thermal Analysis Basis (CETAB):                     .;
" General Electric BWR Thermal Analysis Basis (CETAB):
2.
and Design Application", General Electric Company, January 1977 (NEDO-10958-A).
and Design Application", General Electric Company, January 1977 (NEDO-10958-A).
il
il
: 3. " General Electric Company Analytical Model for Loss-of-Coolant Analysis     .
" General Electric Company Analytical Model for Loss-of-Coolant Analysis in Accordance with 10CFR50 Appendix K Amendment No. 2 - One Recirculation l
in Accordance with 10CFR50 Appendix K Amendment No. 2 - One Recirculation   l Loop Out-of-Service", General Electric Company, Revision 1, July 1978         .    ,
3.
(NEDO-20566-2).
Loop Out-of-Service", General Electric Company, Revision 1, July 1978
                                                                                      'f Enclosure to Letter #TVA-BFNP-TS-Il7, O. E. Gray III to Harold R. Denton,     i               .
,'f (NEDO-20566-2).
Enclosure to Letter #TVA-BFNP-TS-Il7, O. E. Gray III to Harold R. Denton, i
September 15, 1978.
September 15, 1978.
8 a
8 a
i,
i,
                                                                                          . ''[
[
il f
il f
4 t i.
4 t i.
1 ^i I-4
1 ^i I-4
[
[
I\
I\\
6 -
6 -
t! l
t l
                                                                                                  !I i
!I i
p 4
p 4
6-1/6-2 l
6-1/6-2 l
1 l}}
1 l}}

Latest revision as of 18:24, 20 December 2024

Single Loop Operation
ML20028F082
Person / Time
Site: FitzPatrick Constellation icon.png
Issue date: 08/31/1980
From:
GENERAL ELECTRIC CO.
To:
Shared Package
ML20028F081 List:
References
80NED285, NEDO-24281, NUDOCS 8301310130
Download: ML20028F082 (30)


Text

.. _

NEDO 24281 80N ED28's CLASS 4 I

AUGUST 1980 I

k i

FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION l

1 l

u 9:

Is it n u m a s s u m e s. u m ~ m,z m m. - - m 4:

1 l

$882258c2o!884%

GEN ER AL h ELECTRIC P

PDR

4 i

f l

NEDO-24281 80NED285 j

Class I l

August 1980 I

9 i, et I

] l 1

t j i f

1 I i

i i

f*

i, t

i FITZPATRICK NUCLEAR POWER PLANT SINGLE-LOOP OPERATION l

I I

d I.

l l

l

.I I

i

(

l I

i l

I l

I I

f t

t t

i '

i i NUCLEAR POWER SYSTEMS OlVi$lON e GENERAL ELECTRIC COMPANY l

SAN JOSE, CAllFORNI A 95125 i I i

e

' s I,

GEN ER AL $ ELECTRIC L

i


vm---vv--.e w---- -. --

,--,.,..,--,,,,,-...-v

,,,----r

---%-.cw+.--m---#,--,-w.---.~. my--y'-

3,,

- - +. -

++-e e-~m-- ---+

g-y----

l q

f.

NEDO-24281

?

t I

DISC: AIMER GF RESPONSIBILITY j

Ynia doxer:ent was prepared by or for the General Electric Company.

Neither the General Electric Cor:pany nor any of the contributors to i

this doc: cent:

l i

A.

Makaa any varranty or representation, express or implied, with recpect to the accuracy, completeness, or usefulness of the 1

infomation contained in this doc: cent, or that the use of any infcmaticn dicolosed in this document may not infringe privately l

3 t

cuned rights; or I

I B.

Ascumca any responsibility for liability or damage of any kind h

i uhich may result from the use of any infomation disclosed in thia document.

i 4

W ii

.e

g _ _ __

N G

NEDO-24281 TABLE OF CONTENTS Page l-1 1.

INTRODUCTION AND

SUMMARY

2-1 2.

MCPR FUEL CLADDING INTEGRITY SAFE"IY LIMIT 2-1 2.1 Core Flow Uncertainty 2.1.1 Core Flow Measurement During Single Loop 2-1 Operation 2-2 2.1.2 Core Flow Uncertainty Analysis 2-4 2.2 TIP Reading Uncertainty i

3-1 3.

MCPR OPERATING LIMIT 3-1 3.1 Core-Wide Transients 3-2 3.2 Rod Withdrawal Error 3-4 3.3 MCPR Operating Limit 4-1 4.

STABILITY ANALYSIS 5-1 5.

ACCIDENT ANALYSES 5-1 5.1 Loss-of-Coolant Accident Analysis 5-1 5.1.1 Break Spectrum Analysis 5-2 4

5.1.2 Single-Loop MAPLHGR Determination 1

5-2 5.1.3 Small Break Peak Cladding Temperature 5-2 5.2 One-Pump Seizure Accident 6-1 6.

REFERENCES h

I r

ti

]

i d

ii1/1v 1

s

NED0-24281 TABLES Table Title Page 5-1 MAPLilGR Multiplier Cases 5-5 5-2 Limiting MAPLHGR Reduction Factors 5-5 I

?

I l

I I

i l

)

1 4

i 9

4 r

v/vi

'mi NEDO-24281 ILLUSTRATIONS Title Pg Figure 2-5 Illustration of Single Recirculation Loop Operation Flows 2-1 3-5 3-1 Main Turbine Trip With Bypass Manual Flow Control Decay Ratio Versus Power Curve for Two-Loop and Single-4-1 4-2 Loop Operation 5-6 5-1 FitzPatrick Discharge Break Spectrum Reflood Times 5-7 5-2 FitzPatrick Discharge Break Spectrum Uncovered Times 5-8 5-3 FitzPatrick Suction Break Spectrum Reflood Tines 5-9 5-4 FitzPatrick Suction Break Spectrum Unco *ered Times l

l E'

51e i

1

\\

A L

l l

vii/viii

~~~,.--.n w

g-NEDO-24281 1.

INTRODUCTION AND

SUMMARY

FitzPatrick Nuclear Power Plant technical specifications for the

=

The current operation beyond a relatively short period of time if an do not allow plant be returned to service. The FitzPatrick idle recirculation loop cannot (Technical Specification 3.6.Gl shall not be operated Nuclear Power Plant for a period in excess of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> with one recirculation loop out of service.

reduced power with a single recirculation loop The capability of operating at in is highly desirable, from a plant availability / outage planning standpoint, d

the event maintenar.ce of a recirculation pump or other component ren ers one To justify single-loop operation, the safety analyses docu-loop inoperative.

d mente'd in the Final Safety Evaluation Reports and Reference 1 were reviewe Increased uncertainties in the core total flow and for one-pump operation.

TIP readings resulted in an 0.01 incremental increase in the MCPR fuel cladding This 0.01 increase is integrity safety limit during single-loop operation.

No other increase in this limit is reflected in the MCPR operating limit.

required as core-wide transients are bounded by the rated power / flow analyses performed for each cycle, and the recirculation flow-rate dependent rod block and scram setpoint equations given in the technical specifications are adjusted The least stable power / flow condition, achieved by for one-pump operation.

is not affected by one-pump operation.

tripping both recirculation pumps, L

b h

the flow control should be in master manual, During single-loop operation, h

control oscillations might occur in tne recirculation flow control since system under automat!c flow control conditions.

0.84, 0.35, and 0.84 for the 7x7, 8x8, Derived MAPLHGR reduction factors are and 8x8R r ue ! types, respectively.

The dis-The analyses were performed assuming the equalizer valve was closed.

if its charge valve in the idle recirculation loop is normally closed, but closure is prevented, the suction valve in the loop should be closed to prevent of a postulated the loss of Low Pressure Coolant Injection (LPCI) flow out break in the idle suction line, 1-1/1-2 I,

_-g--~-.__-

NED0-24281 2.

MCPk FUEL CLADDING INTEGRITY SAFETY LIMIT for core total flow and TIP reading, the uncertainties used in the Except ctatistical analysis to determine the MCPR fuel cladding integrity safety limit are not dependent on whether coolant flow is provided by one or two Uncertainties used in the two-loop operation analysis are racirculation pumps.

documented in the FSAR for initial cores and in Table 5-1 of Reference 1 for A 6% core flow measurement uncertainty has been established for reloads.

As shown eingle-loop operation (compared to 2.5% for two-loop operation).

below, this value ccuservatively reflects the one standard deviation (ene sigma) accuracy of the core ilow measurement system documented in Reference 2.

The random noise component of the TIP reading uncertainty was revised for single recirculation loop operation to reflect the operating plant test results given in Subsection 2.2 below. This revision resulted in a single-loop opera-The comparable tion process computer uncertainty of 9.1% for reload cores.

The net two-loop process computer uncertainty value is 8.7% for reload cores.

effect of these two revised uncertainties is a 0.01 incremental increase in the required MCPR fuel cladding integrity safety limit.

2.1 CORE FLOW UNCERTAINTY Cl Core Flow Measurement Durine Single Loop Operation l

2.1.1 l

The jet pump core flow measurement system is calibrated to measure core flow when both sets of jet pumps are in forward flow; total core flow is the sum of the indicated loop flows. For single-leop operation, however, the inactive 5

Therefore, the measured ficw in the backflowing jet pumps will be backflcwing.

In pumps must be subtracted from the measured ficw in the active loop.

i jet addition, the jet pump flow coefficient is different for reverse flow than for and the measurement of reverse flow must be modified to account

[

f orward flow, for this difference.

I f

the total core flow is derived by the following For single-loop operation, i

fo rmula:

l Inactive Loop

}

Total Core}

Active Loop j - C IndicatedFlow}.

Indicated Flow /

Flow 2-1 N

wasr -

.c -

NEDO-24281 where C (= 0.95) is defined as the ratio of " Inactive Loop True Flow" to

" Inactive Loop Indicated Flow," and " Loop Indicated Flow" is the flow indi-cated by the jet pump " single-tap" loop flow summers and indicators, which are set to indicate forward flow correctly.

The 0.95 factor was the result of a conservative analysis to appropriately modify the single-tap flow coefficient for reverse flow.*

If a more exact, less conservative core flow measuremenc is required, special in-reactor calibration tests would have to be made. Such calibration tests would involve calibrating core support plate AP versus core flow during two-pump operation i

along the 100% flow control line, operating on one pump along the 100% flow I

control line, una calculating the correct value of C based on the core flow t

derived f rom the core support plate AP and the loop flow indicator readings, f

i 2.1.2 Core Flow Uncertainty Analysis j

The uncertainty analysis procedure used to establish the core flow uncertainty I

for one-pump operation is essentially the same as for two-pump operation, except for some extensions. The core flow uncertainty analysis is described j

17 Reference 2.

The analysis of one-pump core flow uncertainty is summarized

?

below.

l N

For single-loop operation, the total core ficw can be expressed as follows l

(Figure 2-1):

,i W

C A ~ I i

' E 1.here total core flow;

y V

=

l g

q.

active loop flow; and I

W

=

3 t

inactive loop (true) flow, W

=

7 P>

d

  • The expected value of the "C" coefficient is NO.88.

e

~

~

.h wm NEDO-24281 By applying the " propagation of errors" method to the above equation, the variance of the total flow uncertainty can be approximated by:

a\\

[2 2\\

~

+[Q1-a}l j2 +[(1:a}

2 2

2

  • W

+ *C

  • W C

" C 1

y W

Arand k rand

/

sys where uncertainty of total core flow; o

=

y C

_l i

uncertainty systematic to both loops;

~l c.

=

I sys random uncertainty of active loop only; c

=

p Arand I

i random uncertainty of inactive loop only; o

=

y I rand uncertainty of "C" coefficient; and a

=

ratio of inactive loop flow (W ) to active loop flow (W ).

a =

7 g

>
P Resulting from an uncertainty analysis, the conservative, bounding vlaues of s

are 1.6%, 2.6%, 3.5% and 2.8%, respectively.

and oc owsys, cuArand, cwyrand 6

Based on above uncertainties and a bounding value of 0.36 for "a",

the variance 4

of the t tal flow uncertainty is approximately:

.6)2+[lb.6)2-21 (1.6)' + (/ 1 03 c6'

(

+

(

\\

36/

j

=

1-0.36 4

C 1

(5.0%)'

=

1 2-3

'l

r

' W it+1Su n u.

~. _ _. ~.... m.

4 NEDO-24281 k' hen the effect of 4.1% core bypass flow split uncertainty at 12% (bounding case) bypass flow fraction is added to the above total core flow uncertainty, the active coolant flow uncertainty in:

l 0 l' h (4.1%)'

(5.0%)2 b

(.0%)2 + j 2

l

=

=

1-0.12 active

\\

/

j fi coolant i

t which is less than the 6% core flow uncertainty assumed in the statistical f'

analysis.

q

! 4 In su:: nary, core flow during one-pump operation is measured in a conservative i

way and its uncertainty has been conservatively evaluated.

2.2 TIP READING UNCERTAINTY

/

To ascertain the TIP noise uncertainty for single recirculation loop operation, a test was performed at an operating Bk'R.

The test was performed at a power level 59.3% of rated with a single recirculation pump in operation (core flow 46.3% of rated). A rotationally syr: metric control rod pattern existed prior to the test.

Five consecutive traverses were made with each of five TIP machines, giving a i

a total of 25 traverses. Analysis df their data resulted in a nodal TIP noise h

of 2.85%.

Use of this TIP noise value as a component of the process computer, j f total uncertainty results in a one-sigma process computer total uncertainty

(

value for single-loop operation of 9.1% for relcad cores.

h 4

ti n

2-4

I liED0-24281 l

I l

\\

CORE b

WC w,

WA W

WC

  • TOTAL CORE FLOW WA = ACTIVE LOOP FLCW

= INACTIVE LOOP FLCW W) ion Flows Illustration of Single Recirculation Loop Operat Figure 2-1.

I 2-5/2-6

E

{

NED0-24281 t

[

3.

MCPR OPERATING LIMIT I

I 3.1 CORE-k'IDE TRANSIENTS i

i hich Operation with one recirculation loop results in a maximum power output w Therefore, is 20 to 30% below that which is attainable for two-pump operation.

l peration the consequences of abnormal operational transients from one-oop o loop opera-will be considerably less severe than those analyzed from a two-flow decrease and cold water increase tran-For pressurization, hermal and tional mode.

sients, previously transmitted Reload /FSAR results bound both the t overpressere consequences of one-loop operation.

(tur-Figure 3-1 shows the consequences of a typical pressurization transient As can be seen, the consequences of f

bine trip) as a function of power level.

d reduction one-loop operation are considerably less because of the associate in operating power level.

full The consequences from flow decrease transients are also bounded by the A single pump trip from one-loop operation is less severe power analysis.

d initial power than a two-pump trip from full power because of the reduce level.

Cold water increase transients can result from either recirculation pump l

or introduction of colder water into the reactor vessel by speedup or restart, factors are derived assuming The K events such a" loss of feeduater heater.

g both recirculation loops increase speed to the maximum permitted by the scoop tube position. This condition produce: the maximum possible that M-C set ii d from less power increase and, hence, maximum ACPR for transients in t ate When operating with only one recirculation loop, than rated power and flow.

d speed on only one the flew and power increase asscciated with the increase associated with both pumps increasing speed; M-C set will be less than that factors derived with the two-pump assumption are conserva-therefore, the K Inadvertent restart of the idle recirculation g

tive for single-loop operation.

in a neutron flux transient which would exceed the flow pump would result The resulting scram is expected to be less severe than the reference scrat.

The latter event (loss of rated power / flow case documented in the FSAR.

1 3-1

)

L,

~

$ :.s2 s..T 2

.l a.

I SEDO-24281 4

feedwater heating) is generally the most severe cold water increase event with respect to increase in core power. This event is caused by positive reactivity insertion from core flow inlet subcooling; therefore, the event is primarily I

dependent on the initial power level. The higher the initial power level, the 1

greater the CPR change during the transient. Since the initial power level during one-pump operation will be significantly lower, the one-pump cold water increase case is conservatively bounded by the full power (two-pump)

I i

<,l analysis.

,l J l l d From the above discussions, it can be concluded that the transient consequence lE from one-loop operation is bounded by previously submitted full power analysis.

3.2 ROD WITHDRAWAL ERROR The rod withdrawal error at rated power is given in the FSAR for the initial core and in cycle-dependent reload supplemental submittals. These analyses l'

are performed to demonstrate that, even if the operator ignores all instrument l

indications and the alarm which could occur during the course of the transient, the rod block system will stop rod withdrawal at a minimum critical power ratio (MCPR) which is higher than the fuel cladding integrity safety limit. Correc-tion of r.he rod block equation (see the following) and lower power assures that

.,=

the MCPR safety limit is not violated.

1' ;

[

One-pump operation results in backflow through the inactive bank of jet pumps while the flow is being supplied into the lower plenum from the active bank of j

l Because of the backflow through the inactive jet pumps, the present i

jet piutp s.

t rod block equation was conse natively modified for use during one-pump operation I

~

because the direct active-loop flow measurement may not indicate actual flow l

above about 35% drive flow without correction.

A precedure has been established for correcting the rod block equation to for the discrepancy between actual flow and indicated flow in the account active loep. This preserves the original relationship between rod block and actual effective drive flow when operating with a single loop.

3-2

NEDO-24281 The two-pump rod block equation is:

i mW +

RB

- m(100)

RB

=

100 The one-pump equation becomes:

100 ' *(

~ 0 mW + R2 RB

=

where difference, determined by utility, between two-loop and single-aW

=

loop effective drive flow at the same core flow; power at rod blbck in %;

RB

=

flow reference slope for the rod block monitor (RBM);

m =

i drive flow in % of rated; and A

W

=

j?

t p level rod block at 100% flow.

RB 100 i

If the rod block setpoint (RB100) is changed, the equation must be recalculated

^l; using the new value.

3 i

flew biased in the same manner as the rod block The APRM trip settings are Therefore, the APRM rod block and scram trip settings monitor trip setting.

to the same procedural changes as the rod block monitor trip set-are subject ting discussed above.

1 3-3

---e-----

mw-w-

-w--w---

w,-

--e v-

k % 'aET, X.~nw t c~ v 7. c m a a n.sa.u s u a......., _ _ _. _ _

NEDO-24281 3.3 OPERATING MCPR LIMIT i

For single-loop operation, the rated condition steady-state MCPR limit is increased by 0.01 to account for the increase in the fuel cladding integrity safety limit bection 2). At lower flows, the steady-state MCPR operating i

limit is conservatively established by multiplying the rated flow steady-state i

p limit by the K factor. This ensures that the 99.9% statistical limit require-g is always satisfied for any postulated abnormal operational transient.

ment L

l 1

I i

I L

r I

l I

i s

i i

l I

l l

3-4 I

l l

\\

i NED0-24281 i

1160 t

lY ii a

aco l

E 4

2 uso -

5 e

o I

E U

i' 11oo 2

W sooj

~}.io.o a-5 w

E 5

5 i

N i

y w

2 d

f a 'oso s

l 5

4 E

f s

t w

G j 1 4o

.5 t

t to2a 1000 l

900-c RANGE OF EXPECTED -

M AxiquM ONE LOOP POWER OPER ATION l

I I

I 14o o

20

.o so ao too 1;ro eso POWER LEVEL (% NUCLEAR SOILER RATEDI 1

Main Turbine Trip with Bypass Manual Flow Control Figure 3-1.

3-5/3-6 e

^ - ' ~ ' - ' - - - - - _ _ _ _ _

-=mwyy_,_%__

NEDO-24281 4.

STABILITY ANALYSIS The least stable power / flow condition attainable under normal conditions for rated power and occurs at natural circulation with the control rods set j

This condition may be reached following the trip of both recirculation As shown in Figure 4-1, operation along the minimum forced recircula-flow.

2 ble than operating pumps.

tion line with one pump running at minimum speed is more sta is less stable than operating with both with natural circulation flow only, but

?

pumps operating at minimum speed.

l y

During single-loop operation, the flow control should be in master manua,

1:

flow control system since control oscillations might occur in the recirculation under automatic flow control conditions.

't

?

I l

9

,e a

9 m

4-1 AS l

l l

J.-,-

NEDO-24281 1.2 ULTIMATE STASILITY LIMIT 1.0 ------ - = = =

a--

a-==

]

- - -- SINGLE LOOP. PUMP MINIMUM SPEED SOTH LOOPS, PUMPS MINIMUM SPEED c.s I

~O A

.5 9

e Q

o.6

{

z

,o NATURAL

/

RATED FLOW CONTROL LINE d

Q CIRCULATION

/

LINE V

/

' i a4 HIGHEST POWER ATTAINAS LE t

?<

/

FOR SINGLE h

//

LOOP OPER ATION l

J l b o:

. i 1

i i

f, l

{ '.

l I

f I

I o o ao 40 to 80 100 j

I POWER (%)

.l t

Figure 4-1.

Decay Ratio Versus Power Curve for Two-Loop and l 'j Single-Loop Operation

- d 4-2 Id

m w.

Mr-h NEDO-24281 l

l t

t 5.

ACCIDENT ANALYSES l

6 The broad spectrum of postulated accidents is covered by six categories of d2aign basis events. These events are the loss-of-coolant, recirculation pump caizure, control rod drop, main steamline break, refueling, and fuel assembly l

lording accidents. The analytical results for the loss-of-coolant and recir-i culation pump seizure accidents with one recirculation pump operating are Fa 5

given below. The results of the two-loop analysis for the last four events y

are conservatively applicable for one-pump operation.

5.1 LOSS-OF-COOLANT ACCIDENT ANALYSIS I;

(f l

A single-loop operation analysis utilizing the models and assumptions documented 4 I in Ref erence 3 was performed for the FitzPatrick Nuclear Power Plant.

Using l ir

')

this method, SAFE /REFLOOD computer code runs were made for a full spectrum of break sizes for the suction and discharge side breaks. The reflooding time for the single-loop analysis is similar to the two-loop analysis, and the Maximum Average Planar Linear Heat Generation Rate (MAPLHGR) curves currently applied were modified by derived reduction factors for use during one recirculation pump

[i";

ope rat ion.

V t.

5.1.1 Break Spectrum Analysis

'r

\\

fi A break spectrum analysis was performed using the SAFE /REFLOOD cceputer codes f,4 ar.d the assumptions giv1n in Section II.A.7.2.2. of Reference 3.

m b

The discharge break spectrum and the suction break spectrum reflooding times for k

recirculation loop operation are compared to the standard previously per-one t ormed two-loop operation in Figures 5-1 and 5-3.

The uncovered tines (reflood time minus recovery time) for each break spectrum are compared in

}

Figures 5-2 and 5-4 For the FitzPatrick Nuclear Power Plant, the reflooding time for the limiting break in standard two-loop operation is 247 seconds, occurring at 80% of the Desien Basis Accident (DBA) discharge break. The boiline transition time ranges from 9 to 10.i seconds for the three fuel types.

For the sinele-loop analv+1s, B

i 5-1 i

..... i,-:jf f m.__

m NEDO-24281 the most limiting break also occurs at the 80% DBA discharge break, and the reflooding time is 247 seconds. The uncovered time at the most limiting break is 213 seconds for the two-loop analysis and 214 seconds for the single-loop analysis.

5.1.2 Single-Loop MAPLHGR Determination The small difference in uncovered time for the limiting break size would result in a very small change in the calculated peak cladd ag temperature. Therefore, as noted in Reference 3, the one-and two-loop SAFE /REFLOOD results can be con-sidered similar and the generic alternative procedure described in Section II.A.7.4 of this reference was used to calculate the MAPLHGR reduction factors for single-loop operation.

y.

k MAPLHGR reduction factors were determined for the cases given in Table 5-1.

The most limiting reduction factors for each fuel type is shown in Table 5-2.

t One-loop operation MAPLHGR values arc derived by multiplying the current two-loop operation MAPLHGR values by the reduction factor for that fuel type.

As discussed in Reference 3, single recirculation loop MAPLHGR values are f

conservative when esiculated in this manner.

5.1.3 Small Break Peak Cladding Temperature f

r Section II.A.7.4.f.2 of Reference 3 discusses the small sensitivity of the i

y calculated peak clad temperature (PCT) to the assumptions used in the one-pump I

operation analysis and the duraticn of nucleate boiling.

Since the slight increase (%50*F) in PCT is overwhelmingly offset by the decreased MAPLHCR (equivalent to 300* to 500*F *. PCT) for one-pu=p operation, the calculated PCT values for small breaks will be well below the 2200*F 10CFR50.46 cladding temperature limit.

F L

5.2 ONE-PUMP SEIZURE ACCIDENT j

The one-pump seizure accident is a relatively mild event during two-recirculation-pump operation, as documented in References 1 and 2.

Similar analyses were performed to determine the impact this accident would have on

'}

l C.1

EEDO-26281

(

k:

0 t {

one-recirculation-pump operation. These analyses were performed with the models documented in Reference 1 for a large core BWR/4 plant (Reference 4).

!\\i l to The analyses were initialized from steady-state operation at the following initial conditions, with the added condition of one inactive recirculttion loop. Two sets of initial conditions were assumed:

g l\\'

E 1,l (1) Thermal Power = 75% and core flow = 58%

l

'i I

(2) Thermal Power = 82% and core flow = 56%

ld lh 5

These conditions were chosen because they represent reasonable upper limits of 2

h.

single-loop operation within existing MAPLHGR and MCPR limits at the same q

maximum pump speed. Pump seizure was simulated by setting the single operating 4

i pump speed to zero instantaneously.

)Up The anticipated sequence of events following a recirculation pump seizure which occurs during plant operation with the alternate recirculation loop out of service is as follows:

(1) The recirculation loop flow in the loop in which the pump seizure occurs dreps instantaneously to zero.

(2) Core volds increase which results in a negative reactivity inser-tion and a sharp decrease in neutron flux.

) ?

i' (3) Heat flux drops more slowly because of the fuel time constant.

]

.Ii'j*

(4) Neutron flux, heat flux, reactor water level, stean flow, and feed-r j

water flow all exhibit transient behaviors. However, it is not 8

f anticipated that the increase in water level will cause a turbine trip and result in scram.

It is expected that the transient will terminate at a condition of natural circulation and reactor operation will continue. There will also be a small I

decrease in system pressure.

J

NEDO-24281 The minimum CPR for the pump seizure accident for the large core BWR/4 plant was determined to be greater than the fuel cladding integrity safety limit; therefore, no fuel failures were postulated to occur as a result of this analyzed event.

i l

These results are applicable to the FitzPatrick Nuclear Power Plant.

'I,4 14 li1,'

J.

0 r

i

?

ll

,i i-I i

k

NED0-24281 r

l i-Table 5-1 MAPLHGR MULTIPLIER CASES t.

l Fuel Type Cases Calculated i

7x7 80% DBA Discharge Break *

}j p,:

85% DBA Discharge Break p

100% DBA Suction Break I'

8x8 80% DBA Discharge Break

  • K

?

1 85% DBA Discharge Break I,i 9

Is 100% DBA Suction Break j

8x8R 80% DBA Discharge Break *

[,.

4 3

85% DBA Discharge Break

(

100% DBA Suction Break f;f 4

l

  • Most limiting break for MAPLHGR reduction factors.

k

'l 1

(?

Table 5-2 i

l l

LIMITING MAPLHGR REDUCTION FACTORS p

k,

j l

f Fuel Type Reduction Factors 7x7 0.84 l

8x8 0.85 8x8R 0.84 M

e A

I.$

J~d.'.

MEDO-26281 1

3 3

=

8 O

-f O w s!

B

[

i o

E d

e i

p l

{

6

?

l O

l i

mw e

cc:

e 8

1 e

u i

"u I

Q l

Q-V3

!a i

/

O e

a L

O M

a U

2 O

W g

j

~

m i

g 2

r w

C

=

a

-=

3 i.

w

[

%u

    • 9 4

l e

w 4

i

(

I s

n

\\

8 I

i w

w z

/

{

i

=

S s

N N I

I I

I I

o s

s e

s s

e

.s.

s a

a n

a

~

n P**) 3 W11 DNICOOl d 3 to i

i I

. e ed *.

M NEDO-24281 I

?

?

?

.s 81 a

~

8d j'.

E 5i i:

r;

?

I a

I g

l 8

e o

E' C

~

b 8

2 i

l E8 a

?

x i

e E

r e

e a

i

=

a l

3 f

I.

}.

4 I

{

4 r;

h i

R 3

Cs.

N A

N 8

5 N*

)

h.

/

/

S N s's N

I i

l l

k k

8 E

R_

g I*) 36111 G3H3 AODNQ 1V101 5-7

NED0-24281 8

~

1

\\

l i

I L

g l

A 8

L m8d 1

%e i

35

{

I g

j 8

I

\\

\\

y M

a g

\\

t

\\

35 0

O g

8; i

\\

35

\\

1 2

a

\\

s 8

3

)

0 e

U l

c I

I v~.

/

l 8

i 5

1 I

1 1

g 6

3 E

E (m) 3MI LNt0001338 s'

=.>

NEDO-24281 8

e

\\

I I

l 8

~

.8 L

8d 1

NN

\\

a 8

I

\\

p i

g

.g o

\\

o

\\

a:

R 9

i j

E 8

\\

O O

\\

as; c

\\

03 s

1 e

a 5

\\

m a

a c.,

t l

l 5

k, 2

/'

/

s

/

5 i

k j

a j

~

l i

I I

g 3

S E

pas) 3Wil DNICOO7 338 e a.35.v;-

,i, i

1.

i z

z1'ef $' wc~

c T

00 1

/,

0

/

1 9

p sem i

I T

0 f

i 8

de r

/

ev

/

oc 1

Y U

~-

~

m 0

u i

7 r

7 t

/

c Q

e

)

M"M A

p

/

B S

D F

k

/

O a

e

(

r 5

/

e 0

A B

6 E

l n

N fA o

/

i K

t A

c

[

E R

u B

S

[

"=

k c

/

i 5 r

g 7

0 i

t g

/

g7 a

g P

t

^4 z

/

y i

/

F

/

P O

4 P

O e

04 O

L-5 F

O E

W L.

L e

O G r

N W

I u

T S

g i

F ew 0

i 3

w

~

0

~

2 0

0 5

0 0

6 1

0 8

9

$I>G Owc ?$2a J.

O.-

YcsV 1

I

M lu. -

NEDO-24281 6.

REFERENCES

" Generic Reload Fuel Application, General Electric Company", August 1979 1.

(NEDE-240ll-P-A).

Data, Correlation l.l

" General Electric BWR Thermal Analysis Basis (CETAB):

2.

and Design Application", General Electric Company, January 1977 (NEDO-10958-A).

il

" General Electric Company Analytical Model for Loss-of-Coolant Analysis in Accordance with 10CFR50 Appendix K Amendment No. 2 - One Recirculation l

3.

Loop Out-of-Service", General Electric Company, Revision 1, July 1978

,'f (NEDO-20566-2).

Enclosure to Letter #TVA-BFNP-TS-Il7, O. E. Gray III to Harold R. Denton, i

September 15, 1978.

8 a

i,

[

il f

4 t i.

1 ^i I-4

[

I\\

6 -

t l

!I i

p 4

6-1/6-2 l

1 l