Benchmarking of Catawba Nuclear Station Cycles 19-21 Travis Lange, - - PowerPoint PPT Presentation

▶
benchmarking of catawba nuclear station cycles 19 21
SMART_READER_LITE
LIVE PREVIEW

Benchmarking of Catawba Nuclear Station Cycles 19-21 Travis Lange, - - PowerPoint PPT Presentation

Sep 22, 2022 346 likes •678 views

Benchmarking of Catawba Nuclear Station Cycles 19-21 Travis Lange, Jason Young, Brad Black Catawba Catawba Nuclear Station SC outside of Charlotte Two Unit Westinghouse 4-loop PWR Unit 1 currently on cycle 23 Unit 2 beginning

slide-1
SLIDE 1

Benchmarking of Catawba Nuclear Station Cycles 19-21

Travis Lange, Jason Young, Brad Black

slide-2
SLIDE 2

Catawba

  • Catawba Nuclear Station
  • SC outside of Charlotte
  • Two Unit Westinghouse 4-loop

PWR

  • Unit 1 currently on cycle 23
  • Unit 2 beginning cycle 22

2

slide-3
SLIDE 3

Duke Energy Core Design

Core Design Initial Safety Analysis Pattern Selection

3

slide-4
SLIDE 4

Risk Tolerance

  • BOA
  • Risk thresholds (lbm of core boron, crud thickness, steaming rate) effectively considered

‘limits’ when undergoing a standard core design process

  • Risk thresholds rarely breached without an outside compelling force (such as transition to

24 month cycles)

  • Normal designs have generally not been pursued with BOA risks
  • CIPS
  • Magnitude of CIPS effect on axial offset is difficult to predict, especially in cores without a

history of CIPS

  • Not sufficient confidence in deriving the resultant axial offset from BOA results to challenge

these thresholds

  • Core designs remain CIPS-conservative

4

slide-5
SLIDE 5

Safety Analysis

  • CIPS affects many assumptions about core power distributions
  • Axial profile at steady state
  • Reactivity in core
  • Continued operation with CIPS erodes excess shutdown margin
  • Large power defect due to
  • Reactivity addition when boron/crud deposits disappear during a trip
  • Additional axial flux redistribution (more positive AO at HZP)
  • Must assume a trip would completely remove boron in crud
  • Exposes top of core where burnup has been held abnormally low
  • Fresh boron can take its place, exacerbating axial offset

5

slide-6
SLIDE 6

Delivering the Nuclear Promise

  • Delivering the Nuclear Promise
  • Duke Energy is committed to providing safe, reliable, and economically competitive nuclear

energy for ratepayers

  • Better quantifying CIPS risk is a potential area for improvement in designing more cost

competitive core designs while maintaining safe operation

  • Knowledge of likely CIPS effects on power distributions would allow technical experts to

propose designs with a potential for light CIPS, as well as examine the actual effects of CIPS on our internal safety analysis methods

  • CASL
  • By first matching BOA results and eventually predicting CIPS and projecting CIPS effects,

CASL can build confidence in utilities that VERA can be used to inform core designs with regards to CIPS risk

  • VERA can become a tool that would allow pursuing more economic core designs based

upon an actual understanding of the true risk and likelihood of CIPS in candidate core designs

6

slide-7
SLIDE 7

VERA Catawba 2 Cycles 19-21 Benchmarking Summary

Travis Lange

slide-8
SLIDE 8

8

Content

  • Review of VERA results for Jump In (cycles 19-21)

– ZPPT – Full cycle comparisons

  • Critical Boron
  • AO
  • Cycle 22 results

– ZPPT – Preliminary CIPS results

slide-9
SLIDE 9

Catawba 2 Jump In Review

Cycles 19-21

slide-10
SLIDE 10

10

Cycle 19 ZPPT

C2C19 BOC HZP ARO MeasuredDuke VERA Critical Boron Conc (PPM)* 1944 1955 1958 ITC (pcm/°F)

  • 4.53
  • 4.21
  • 5.15

MTC (pcm/°F) Boron Worth (pcm/ppm)

  • 6.12
  • 6.25

C2C19 Individual Bank Worths (pcm) Measured Duke % Diff VERA % Diff Control Bank A 385.2 393.8 2.2% 420 9.1% Control Bank B 646.5 614.6

  • 4.9%

572

  • 11.6%

Control Bank C 983.5 959.3

  • 2.5%

959

  • 2.5%

Control Bank D 467.9 461.2

  • 1.4%

456

  • 2.6%

Shutdown Bank A 156.5 157.9 0.9% 143

  • 8.6%

Shutdown Bank B 1200.7 1145.8

  • 4.6%

1115

  • 7.1%

Shutdown Bank C 367.1 359.6

  • 2.0%

341

  • 7.2%

Shutdown Bank D 366.9 360.6

  • 1.7%

341

  • 7.1%

Shutdown Bank E 650.3 659 1.3% 674 3.6% Total 5224.6 5111.8

  • 2.2%

5020

  • 3.9%
slide-11
SLIDE 11

11

Cycle 20 ZPPT

C2C20 BOC HZP ARO MeasuredDuke VERA Critical Boron Conc (PPM)* 1949 1977 1950 ITC (pcm/°F)

  • 4.4
  • 4.16
  • 5.7

MTC (pcm/°F) Boron Worth (pcm/ppm)

  • 6.09
  • 6.23

C2C20 Individual Bank Worths (pcm) Measured Duke % Diff VERA % Diff Control Bank A 415.8 434.3 4.4% 425 2.2% Control Bank B 641.6 609.9

  • 4.9%

616

  • 4.0%

Control Bank C 955.7 948.7

  • 0.7%

927

  • 3.0%

Control Bank D 523.1 516

  • 1.4%

517

  • 1.3%

Shutdown Bank A 189.9 182.1

  • 4.1%

188

  • 0.8%

Shutdown Bank B 952.4 944.6

  • 0.8%

934

  • 1.9%

Shutdown Bank C 386.4 367.9

  • 4.8%

376

  • 2.7%

Shutdown Bank D 386.7 367.9

  • 4.9%

375

  • 2.9%

Shutdown Bank E 507.4 519 2.3% 510 0.4% Total 4959 4890.4

  • 1.4%

4868

  • 1.8%
slide-12
SLIDE 12

12

Cycle 21 ZPPT

BOC HZP ARO MeasuredDuke VERA Critical Boron Conc (PPM)* 1922 1923 1903 ITC (pcm/°F)

  • 4.73
  • 4.7
  • 6.1

MTC (pcm/°F) Boron Worth (pcm/ppm)

  • 6.11
  • 6.26

Individual Bank Worths (pcm) Measured Duke % Diff VERA % Diff Control Bank A 314.6 332.6 5.7% 338 7.5% Control Bank B 715.8 675.6

  • 5.6%

683

  • 4.5%

Control Bank C 955.3 946.6

  • 0.9%

945

  • 1.1%

Control Bank D 545.5 538.1

  • 1.4%

537

  • 1.6%

Shutdown Bank A 160.7 167 3.9% 167 3.7% Shutdown Bank B 1165.6 1113.8

  • 4.4%

1106

  • 5.1%

Shutdown Bank C 416.2 408.1

  • 1.9%

405

  • 2.7%

Shutdown Bank D 415.9 409.1

  • 1.6%

407

  • 2.1%

Shutdown Bank E 535.5 528

  • 1.4%

523

  • 2.4%

Total 5225.1 5118.9

  • 2.0%

5111

  • 2.2%
slide-13
SLIDE 13

13

Critical Boron

Measured VERA Diff (VERA-measured) c19 1944 1958 14 c20 1949 1950 2 c21 1922 1903

  • 19

Initial Critical Boron [ppm]

  • 30
  • 20
  • 10

10 20 30 40 50 100 200 300 400 500 600 Burnup [EFPD]

VERA Critical Boron Differences (Predicted - Measured)

c19 C20 c21

slide-14
SLIDE 14

14

Axial Offset

*measured data comes from COMET data from Duke C19 still has effects from the jump in cycle at 18

c19 c20 c21 Whole cycle 1.34% 1.10% 0.99% >150 EFPD 0.65% 0.32% 0.37% >250 EFPD 0.73% 0.19% 0.08% RMS Error of Axial Offset Differences (VERA - measured*)

  • 3.00%
  • 2.00%
  • 1.00%

0.00% 1.00% 2.00% 3.00% 50 100 150 200 250 300 350 400 450 500 Burnup [EFPD]

VERA AO Comparison (predicted - measured)

VERA c19 VERA c20 VERA c21

slide-15
SLIDE 15

Cycle 22 Results

Non-CIPS

slide-16
SLIDE 16

16

Cycle 22 ZPPT

C2C22 BOC HZP ARO MeasuredDuke VERA Critical Boron Conc (PPM)* 1970 1963 ITC (pcm/°F)

  • 4.02
  • 5.13

MTC (pcm/°F) Boron Worth (pcm/ppm)

  • 6.06
  • 6.23

C2C22 Individual Bank Worths (pcm) Duke VERA % Diff Control Bank A 510 521 2.2% Control Bank B 508 493

  • 3.0%

Control Bank C 894 888

  • 0.7%

Control Bank D 625 620

  • 0.8%

Shutdown Bank A 177 172

  • 3.0%

Shutdown Bank B 804 792

  • 1.4%

Shutdown Bank C 373 366

  • 2.0%

Shutdown Bank D 372 365

  • 1.9%

Shutdown Bank E 447 441

  • 1.3%

Total 4710 4658

  • 1.1%
slide-17
SLIDE 17

17

VERA Cycle 22 Boron Comparison

  • 15
  • 10
  • 5

5 10 15 20 25 30 100 200 300 400 500 600 Boron [ppm] Burnup [EFPD]

C22 Boron Difference (VERA-Duke)

slide-18
SLIDE 18

18

VERA Cycle 22 AO Comparison

  • 0.80%
  • 0.60%
  • 0.40%
  • 0.20%

0.00% 0.20% 0.40% 0.60% 100 200 300 400 500 600 Axial Offset Burnup [EFPD]

C22 Axial Offset Difference (VERA - Duke)

slide-19
SLIDE 19

19

C22 Power Peaking Comparisons

  • 0.50%

0.00% 0.50% 1.00% 1.50% 2.00% 2.50% 3.00% 3.50% 100 200 300 400 500 600 % Difference Burnup [EFPD]

C22 Power Peaking Comparisons (VERA - Duke)

F_assy FdH Fq

slide-20
SLIDE 20

20

Max Power Location Comparisons

Burnup EFPD DUKE VERA DUKE VERA 4 H-09 H-09 C-12 C-12 C-12 163 C-12 139 12 C-11 C-11 C-12 C-12 C-12 163 C-12 139 25 C-11 C-11 C-12 C-12 C-12 163 C-12 149 50 C-11 C-11 C-12 C-12 C-12 163 C-12 149 75 C-11 C-11 C-12 C-12 C-12 163 C-12 149 100 E-11 E-11 C-11 C-11 C-11 163 C-11 139 150 D-10 D-10 E-11 E-11 C-11 117 C-11 106 200 D-10 D-10 D-10 D-10 G-14 117 G-14 96 250 D-10 D-10 D-10 D-10 B-08 102 H-14 86 300 D-10 D-10 D-10 D-10 D-10 102 D-10 86 350 D-10 D-10 D-10 D-10 D-10 102 E-09 86 400 D-10 D-10 D-10 D-10 H-14 71 E-09 55 450 D-10 D-10 D-10 D-10 B-08 71 E-09 55 499 D-10 D-10 D-10 D-10 B-08 71 E-09 55 DUKE VERA Max Pin Location Max Fq Position Max Assembly Location

slide-21
SLIDE 21

Preliminary C22 CIPS Results

Boron Mass Density Pin Power Differences

slide-22
SLIDE 22

22

VERA vs BOA Pin Powers 300 EFPD at 300 cm

slide-23
SLIDE 23

23

Radial Boron Mass Buildup 300 EFPD at 300 cm

slide-24
SLIDE 24

24

Axial Boron Deposition Channel 81

Top left of assembly E11

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 50 100 150 200 250 300 350 400 boron mass density [mg/cm^2] boron mass [1000*lbm] axial height [cm]

Axial Boron Mass Deposition

BOA VERA boron

slide-25
SLIDE 25

25

C22 Core Boron Buildup

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 100 200 300 400 500 600 Boron Mass [100*lbm] Time [days] BOA Boron Mass VERA CIPS

slide-26
SLIDE 26

26

C22 CIPS Axial Offset

  • 4.0%
  • 3.5%
  • 3.0%
  • 2.5%
  • 2.0%
  • 1.5%
  • 1.0%
  • 0.5%

0.0% 0.5% 100 200 300 400 500 600 Axial Offset Burnup [EFPD]

C22jj Axial Offset Comparison

c22 No Crud C22 VERA CIPS - 0.357 lbm boron

slide-27
SLIDE 27

27

VERA Pin Steaming Rate Difference

slide-28
SLIDE 28

28

VERA Pin Power Difference

slide-29
SLIDE 29

29

Pin Exposures Diff

slide-30
SLIDE 30

30

Summary and Next Steps

  • Successful Jump In

– First model of an active core with history effects

  • CIPS models show excellent feedback

– Consider adding models (boron re-solution, etc.) – Need to define criteria for acceptable design

  • A Big Thanks

– Jason Young, Brad Black, Nick Stehle, Stanley Hayes, Jonathan Hackelton, and Matt Cameron for their expertise and continued support. – Those that made it possible for me to visit Duke: – Scott Thomas, Mike Blom

slide-31
SLIDE 31

31

www.casl.gov