Document: NUREG-0800
Document ID: 145ec0f9-012b-4669-9627-ed1b1d0cce95
Document Type: srp
Title: THERMAL AND HYDRAULIC DESIGN
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070412.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4.4
CFR Part: 
CFR Title: 

Content:
cceptable static and dynamic operation of the integrated system when compared with the predictions of the thermal-hydraulic design analyses. The reviewer should consult with HICB concerning the design acceptability of the hardware portion of the core protection systems.55 The reviewer is to establish that the thermal-hydraulic design and its characterization by MCHFR or DNBR have been accomplished and are presented in a manner which accounts for all possible reactor operating states as determined from operating maps. In this regard, the reviewer must confirm that the power distribution assumptions of SAR Section 4.4 are a conservative (i.e. worst-case) accounting of the power distributions derived in SAR Section 4.3 from core physics analyses, and that the latter analyses include an acceptable calculation of local void fractions. He must also confirm that the mass flux used in these calculations takes into account the core flow distribution (including that for partial loop operation) and the worst case of core bypass flow. The reviewer confirms that the primary coolant flow range shown in the operating map will be verified by prestartup measurements. The reviewer evaluates information in the applicant's safety analysis report with regard to thermal-hydraulic stability concerns during normal operations, anticipated operational occurrences, and ATWS events for conformance with specific criteria II.3. Specifically for 56 4.4-9 DRAFT Rev. 2 - April 1996 BWR applications, the reviewer assesses the applicants design in accordance with the following:57 1. The reactor and associated systems include provisions to facilitate manual or automatic protective action to ensure that specified acceptable fuel design limits are not exceeded in the event of thermal hydraulic instabilities in accordance with the recommendations of topical reports NEDO-31960 and NEDO-31960 Supplement 1 as approved by the related NRC SER (Reference 15).58 2. Thermal-hydraulic behavior during ATWS events