ML19331A067
| ML19331A067 | |
| Person / Time | |
|---|---|
| Issue date: | 11/26/2019 |
| From: | Riccardella P Advisory Committee on Reactor Safeguards |
| To: | Margaret Doane NRC/EDO |
| Wang, W, ACRS | |
| References | |
| NUREG/KM 0013 | |
| Download: ML19331A067 (3) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, DC 20555 - 0001 November 26, 2019 Ms. Margaret M. Doane Executive Director for Operations U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
NUREG/KM-0013, CREDIBILITY ASSESSMENT FRAMEWORK FOR CRITICAL BOILING TRANSITION MODELS - A GENERIC SAFETY CASE TO DETERMINE THE CREDIBILITY OF CRITICAL HEAT FLUX AND CRITICAL POWER MODELS, DRAFT REPORT FOR COMMENT
Dear Ms. Doane:
During the 668th meeting of the Advisory Committee on Reactor Safeguards, November 6-8, 2019, we reviewed the staffs knowledge management publication, NUREG/KM-0013, Credibility Assessment Framework for Critical Boiling Transition Models - A Generic Safety Case to Determine the Credibility of Critical Heat Flux and Critical Power Models, Draft Report for Comment. Our review was also informed by staff presentations on April 18, 2019, and August 21, 2019, to the Thermal-Hydraulic Subcommittee, during which a draft of the assessment framework was successfully applied to the staffs review of the D5 correlation for SVEA-96 Optima3 fuel.
CONCLUSION AND RECOMMENDATION
- 1. The credibility assessment framework documented in NUREG/KM-0013 is an innovative technical approach to review the adequacy of data-driven models.
- 2. Extending this framework to other data-driven model applications should be explored.
DISCUSSION NUREG/KM-0013 offers a systematic and auditable approach to the review of data-driven models, also referred to as correlations. Such models are used across the industry to apply results from separate effects experiments to licensing calculations.
The credibility assessment framework considers three high-level decisions that assess: the goodness of the experimental data, the adequacy of the model generation, and the validation of the final correlation and its uncertainties. The framework allows the staff to systematically break down their review into small logical segments that allow efficient evaluation of these high-level decisions. One worthy example is how the methodology allows the objective definition of subjective terms such as safe. In the process, the evaluation documents the review in an auditable way that can be easily traced and updated for future applications.
M. Doane Even though NUREG/KM-0013 focuses exclusively on the assessment of critical boiling transition models, this approach could be used for other data-driven models and its use should be explored. For example, a similar approach could be used to assess correlations for experimental material property data, CRUD (Chalk River Unidentified Deposit or Corrosion Residual Unidentified Deposit) deposition and removal from fuel, or thermal-hydraulic parameters such as heat transfer coefficients.
SUMMARY
The credibility assessment framework documented in NUREG/KM-0013 is an innovative technical approach to review the adequacy of data-driven models. Extending this framework to other data-driven model applications should be explored.
Sincerely,
/RA/
Peter Riccardella Chairman REFERENCE
- 1. NUREG/KM-0013. Credibility Assessment Framework for Critical Boiling Transition Models - A Generic Safety Case to Determine the Credibility of Critical Heat Flux and Critical Power Models, Draft Report for Comment, March 2019 (ADAMS Accession Number ML19073A249).
M. Doane November 26, 2019
SUBJECT:
NUREG/KM-0013, CREDIBILITY ASSESSMENT FRAMEWORK FOR CRITICAL BOILING TRANSITION MODELS - A GENERIC SAFETY CASE TO DETERMINE THE CREDIBILITY OF CRITICAL HEAT FLUX AND CRITICAL POWER MODELS, DRAFT REPORT FOR COMMENT Accession No: ML19331A067 Publicly Available Y Sensitive N Viewing Rights:
NRC Users or ACRS Only or See Restricted distribution *via email OFFICE ACRS/TSB SUNSI Review ACRS/TSB ACRS ACRS NAME WWang WWang LBurkhart (KHoward for)
SMoore PRiccardella (SMoore for)
DATE 11/26/2019 11/26/2019 11/26/2019 11/26/2019 11/26/2019 OFFICIAL RECORD COPY