Development of Validation System for Subchannel Analysis Codes under Steady-State PWR Conditions

Subchannel analysis code plays an essential role for the thermal hydraulic design of PWR cores. It calculates subchannel-wise local properties under single- and two-phase flow conditions which are used as input parameters for evaluating design parameters such as minimum DNBR and maximum fuel temperature. A validation system for subchannel analysis codes for steady-state conditions is provided in this study through investigation of validation status of existing subchannel codes, review of licensing guideline for thermal-hydraulic codes, and establishment of thermal hydraulic data base for test bundles. Thermal hydraulic test data has been procured for the following experiments: CNEN 4x4 flow distribution test, CU 4x4 flow and enthalpy distribution test, PNL 7x7 flow blockage test, GE 3x3 two-phase flow and quality distribution test, CE 15x15 inlet jetting test, WH 14x14 inlet blockage test, PNL 2x6 low flow test, ISPRA 4x4 two-phase flow and quality distribution test, FRIGG 36-rod void distribution test, Zion-1 plant FA exit temperature distribution test. Sampling analysis for each test has been conducted by employing KAERI inhouse subchannel analysis code MATRA. The state-of-the-art for subchannel thermal hydraulic analysis models such as void fraction correlations, crossflow and turbulent mixing models, and heat transfer correlations was also investigated