THERMAL-HYDRAULIC ANALYSIS OF CORE SHROUD CRACK FOR CHINSHAN BWR 4 UNIT-2 USING RETRAN-02/MOD5/

The RETRAN analyses of three areas of thermal-hydraulic concerns are p resented. The first evaluated whether a 360-deg through-wall crack cou ld be detected based on system response with leakage through the crack . The second analysis was to identify the hydraulic load on the shroud and possible consequences early in the main steam-line break. The las t was the evaluation of the thermal limit (Delta CPR) of limiting tran sients with leakage. Some Of the analyses were used for justification of continued operation of the current cycle, and some will be useful i n the evaluation of the repair design.