Westinghouse Non-Proprietary Class 3

L TR-NRC-17-23 NP-Attachment

Supporting Information for the NRC Audit of the D5 CPR Correlation (Non-Proprietary)

March 2017

Westinghouse Electric Company 1000 Westinghouse Drive

Cranberry Township, PA 16066

© 20 17 Westinghouse Electric Company LLC All Rights Reserved

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• Introduction

• Purpose and Desired Outcome

• Day 1 - RAI 36

• Day 2 - RAI 36 I Other RAI Discussions

• Day 3 - RAI 36 I Other RAI Discussions

• Summary and Closeout

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• Meeting Location and Emergency Response protocol - Building exits and muster point

• March Nuclear Safety Culture Trait at Westinghouse:

Decision Making

Attributes: • DM.1 Consistent Processes

• DM.2 Conservative Bias

• DM.3 Accountability for Decisions

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Audit Participants

- Westinghouse : • Uffe Bergmann • Juan Casal • Patricia Quaglia • Jean-Marie Le Corre (by phone) • Gunilla Norback (by phone) • Ed Mercier • Brad Maurer

- NRC: • Joshua Kaizer • Reed Anzalone • Josh Whitman • John Lehning • Kate Lenning

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• Purpose of the Audit - Discuss the outstanding RAls related to the review of

WCAP-17794-P (05 CPR Correlation)

• Desired Outcome - Reach a common understanding regarding responses to

the RAls which will enable completion of a successful review for the topical report going forward

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• Requests for Additional Information (35) - Responses submitted August 2016 - Additional RAls:

• RAI 36 - November 2016 • RAI 37 - with Audit Plan

• Resolutions - RA Is resolved ( 21 ) - 1 , 2, 5, 8, 1 0, 11 , 12, 1 3, 14, 1 5, 1 6, 1 9,

21, 23, 24,26,27, 30, 31, 32, and 35

• To Be Addressed in the Audit - Require further discussion (7) - 7, 9, 20, 22, 25, 33, and 34 - Supporting Information provided to aid discussion (9) - 3, 4,

6, 17, 18, 28, 29, and 36, 37

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• CPR Critical Power Ratio

• FRIGG Thermal-Hydraulic Test Loop at the Westinghouse Facilities in Vasteras, Sweden

• SLMCPR Safety Limit Minimum Critical Power Ratio

• TC Thermocouple

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Westinghouse Non-Proprietary Class 3

RAls 3, 28, 37 © 2017 Westinghouse Electric Company LLC. All Rights Reserved

L TR-NRC-17-23 NP-Attachment

Data statistics supporting RAI 3 • •

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Westinghouse Non-Proprietary Class 3

RAls 3, 28, 37 © 2017 Westinghouse Electric Company LLC. All Rights Reserved

L TR-NRC-17-23 NP-Attachment

- Data statistics supporting RAI 37 - . ~ ~

a,b,c

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Westinghouse Non-Proprietary Class 3

RAls 3, 28, 37 Summary and Discussion

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© 2017 Westinghouse Electric Company LLC. All Rights Reserved

L TR-NRC-17-23 NP-Attachment

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• Frequency of TCs registering dryout at Spacer 2, coincident with TCs at other elevations, is[ ]'d~ring the cosine test

• Repeated data points at[

Jae radial power distribution are shown below (same as discussed in

previous RAI answer, but now labelled according to TC elevation) - No trend observed in CPR error for dryout registered by TCs at Spacer 2

a,b,c

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• Repeat tests were performed at[ r·c subcooling, and at specific flow levels. The radial power distribution was as close to[

Ja,c • In principle the repeat points are taken at the same

conditions, but to account for any small deviations, a comparison of CPR is more appropriate than comparing the measured critical powers directly

[ ]a,c

• Hence, the derived standard deviation of is indeed representative of (only) the measurement uncertainty (since nearly identical input conditions were used in the CPR correlation)

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• Heat losses were experimentally determined after the latest upgrade of the FRIGG loop, and have since then been applied generically in later tests.

= [ r·c • The heat losses are applied directly to the measured critical power, thus

reducing it by[ Ja,c a,c • As part of FRIGG procedures a heat balance test is

performed before each test campaign to verify applicability of the above values Ja,c - Conditions: [ different

powers - Example test matrix applied before the cosine test is

shown on right. It covers changes in outlet temperature of( Ja,c @Westinghouse

17

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