Document: NUREG-0800
Document ID: 8da52d2b-9980-4076-8056-2cafebb25ed6
Document Type: srp
Title: THERMAL AND HYDRAULIC DESIGN
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550060.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4.4
CFR Part: 
CFR Title: 

Content:
ranges of applicability specified for accepted analysis methods, and (4) the design is within the criteria specified in Subsection II, above, and is not an unexplained or unwarranted extrapolation of other thermal-hydraulic designs. 4. The reviewer evaluates the analytical methods used in the thermal-hydraulic analysis, including the applicability of the codes and correlations used and the uncertainty analysis methodologies implemented. For transient analysis, the setpoint limits and instrumentation uncertainty values used for establishing steady-state conditions preceding transient initiation should be evaluated to ensure appropriate conservatism. The review examines the method of employing peaking factors and hot channel factors in the thermal-hydraulic analysis. The basis for the input parameters used in the uncertainty evaluation and the resulting uncertainty in reactor thermal-hydraulic parameters should also be evaluated. 5. The reviewer does not routinely evaluate calculations. However, the reviewer should 4.4-9 Revision 2 - March 2007 ensure that those applications based on statistical design methodologies include the coefficients required by the statistical model and define the parameter ranges for which the coefficients are applicable. Uncertainties in computer codes, correlations, design methods, and setpoint methodologies should be quantified and the method(s) of accounting for these uncertainties in the design procedures should be discussed. For example, the sensitivity factors and their ranges of applicability must be reviewed for those plants using the Westinghouse revised thermal design procedure (“Revised Thermal Design Procedure,” WCAP-11397-P-A, Westinghouse Electric Corporation, July 1975). On occasion (e.g., if a new design or new design method is proposed), the staff or consultants, under the direction of the primary review organization, perform independent analyses. These analyses verify the design or establish the range of applicability