Document: NUREG-0800
Document ID: 54e3d49d-900d-4fe8-9297-2fc04501e4e0
Document Type: srp
Title: THERMAL AND HYDRAULIC DESIGN
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340664.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4.4
CFR Part: 
CFR Title: 

Content:
y. 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 deter- mined 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 ensures that adequate account is taken of the effect of crud in the primary coolant system, such as in the calculation of CHF in the core, heat transfer in the steam generators, and pressure drop throughout the RCS. The reviewer is to examine the calculation of hydraulic loads for normal operations, including anticipated transients, to ensure they are properly estimated for the worst cases. Worst case -hydraulic loads for normal oper- ations are to be provided for use in the analysis of lifting force of the fuel (SRP Section 4.2). CPB will also provide consultation to RSB upon request, regarding calculations for postulated accident conditions. MEB reviews the adequacy of components and structures under accident loads (SRP Section 3.9.2) and CPB determines that a coolable core geometry is maintained (SRP Section 4.2). 4.4-5 Rev. 1 - July 1981 The reviewer should ensure that an adequate loose parts monitoring system is provided. At the CP level, the design criteria for the system and the types, locations, and methods of mounting all intended sensors should be reviewed.