含气率对PTS时压力容器内流动与传热的影响

本文对反应堆压力容器紧急安注时的流动与传热特性在1/10的模型上进行了流动可视化、局部传热系数以及混合函数的试验研究。针对三个热冲击敏感区域的部分测点,比较了环腔流速为0.5m/s、安注流速为1～30 m/s时不同含气率对下降环腔内流动与传热特性的影响,得出并分析了不同测点传热系数、混合函数的变化规律。研究结果表明:随着含气率增大,安注流体与环腔流体的混合增强;下降环腔内的含气率对小安注流速时的流动与传热影响显著,而对大安注流速时影响较小。

THE EFFECT OF VOID FRACTION ON FLOW AND HEAT TRANSFER IN PRESSURE VESSEL AT PTS

In this paper, the experimental investigation on characteristics of flow and heat transfer when cold water is immediately injected are performed for reactor pressure vessel. The experiments include three parts of flow visualization, Local heat transfer coefficient and mixture function, and it is performed on a 1/10 model. For part measurement points on three areas sensitive to thermal shock, the effects of different void fraction on characteristics of flow and heat transfer are compared when flow rate of downcomer is 0.5 m/s and flow rate of safety injection is 0-30 m/s. The change rule of heat transfer coefficient and mixture function are gained and analysed. From theses studies, it is indicated: with the void fraction increasing, the mixing of safety injection fluid with the fluid in the downcomer becomes increasingly strong. And the effect of the void fraction on the flow and heat transfer at small flow rate of safety injection is becoming remarkable. However, the void fraction has slight effect on the flow and heat transfer when the injection flow rate is high.