基于TEXAS-Ⅴ的AP1000堆外蒸汽爆炸分析

Analysis of AP1000 Ex-vessel Steam Explosion Behavior Using TEXAS-Ⅴ Code

TEXAS-Ⅴ是一维三相瞬态蒸汽爆炸数学物理分析程序,本文采用TEXAS-Ⅴ程序对AP1000堆外蒸汽爆炸进行分析研究。结果表明:熔融物在粗混合阶段不断碎裂,并与冷却剂发生剧烈热量交换;AP1000堆外蒸汽爆炸的压力波随传播强度逐渐降低,压力波的传播会触发熔融物前沿后的熔融物碎裂产生更强的压力波,峰值可达70 MPa,且熔融物液柱具有合适的粗混合时间,较大的初始注入速度以及较大的注入直径能触发蒸汽爆炸产生更为强烈的压力波,具有更大的危险性。

T EXAS‐Ⅴ is a transient ,one‐dimensional and three‐field mathematical phys‐ics analysis code for steam explosion .TEXAS‐Ⅴ code was applied to simulate ex‐vessel steam explosion of AP1000 under severe accident condition .The results indicate that the molten fuel fragments continuously and transfers heat acutely to the coolant during the mixing phase . AP1000 ex‐vessel steam explosion pressure wave intensity gradually decreases during its propagation procedure and it may trigger a stronger pressure wave by causing molten fuel fragmentation after the leading ones . The maximum pressure predicted by TEXAS‐Ⅴ is 70 MPa .The ex‐vessel steam explosion with larger melt inject diameter ,higher initial inject velocity and appropriate mixing time can induce a more violent pressure wave in the explosion phase ,which is more dangerous .