원자로 용기와 단열재 사이의 자연순환 이상유동에 관한 연구

초록

To observe and evaluate the two-phase natural circulation phenomena through the gap between the reactor vessel and the insulation in the APR1400 under external reactor vessel cooling, the T-HERMES program has been performed, that is, the T-HERMES-SCALE, T-HERMES-SMALL, HERMES-HALF, and T-HERMES-CFD studies. The HERMES-HALF is a non-heating experimental study on the two-phase natural circulation through the annular gap between the reactor vessel and the insulation. From the experimental flow observation, the recirculation flows in the near region of the shear key were observed. On the higher air injection rate condition, higher recirculation flows in the near region of the shear key were observed. All injected air could not pass through the minimum gap region, that is, choking phenomena near the minimum gap region occurred. By the HEMRES-HALF experiments, the circulation flow rates increased as air injection rate, inlet, and outlet area increased. The experimental results were also compared with CFX-5.6 code analysis.