Document: NUREG-0800
Document ID: 2bca792d-0e88-4e2d-b437-be572ed57a48
Document Type: srp
Title: REVIEW OF TRANSIENT AND ACCIDENT ANALYSIS METHODS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0708/ML070820123.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.0.2
CFR Part: 
CFR Title: 

Content:
h as equations that relate the shearing stresses to the rate of strain (the velocity field). Constitutive Equations and correlations required to close the field equations so that Equations they may be solved. They relate unknown quantities to the variables of the field equations. They may include physical correlations of transport phenomena such as equations that relate the shearing stresses to the rate of strain (the velocity field). Critical Power Ratio The ratio of assembly power at which critical heat flux occurs to the actual assembly power. Code Scaling, A process to determine the applicability, scalability, and uncertainty of Applicability, a computer code in simulating an accident or other transient. A PIRT and Uncertainty process is normally embedded within a CSAU process. See Reference 1. Empirical Derived from experimental data without recourse to physical modeling. Evaluation Model Calculational framework for evaluating the behavior of the reactor system during a postulated Chapter 15 event, which includes one or more computer programs and all other information needed for use in the target application. Field Equations Equations that are solved to determine the transport of mass, energy, and momentum throughout the system. 15.0.2-18 March 2007 Figures of Merit Quantitative standards of acceptance that are used to define acceptable answers for a safety analysis (e.g., DNBR limits and fuel temperature limits). Frozen The condition whereby the analytical tool(s) and associated facility input decks remain unchanged (and under configuration control) throughout a safety analysis thereby ensuring traceability of, and consistency in, the final results. General Design Design criteria described in Appendix A to 10 CFR Part 50. Criteria Homogeneous An analytical model for two-phase flow that assumes (1) both phases Equilibrium Model move at the same velocity, (2) the fluid is in thermal equilibrium, and (3) the flow is isentropic and steady. Integral Effects An