导流围板对堆芯入口流量分配影响的数值分析

Numerical Analysis of Flow Skirt Influence on Core Inlet Flow Distribution

堆芯入口流量的不均匀分配会引起堆芯局部温度变化较大,给反应堆安全运行带来不利影响。堆芯流量分配装置采用导流围板设计,为揭示导流围板对流量分配的影响,在保证其他结构设计不变前提下,本文通过改变导流围板顶部水隙d,以及导流围板侧面支承板的长度t,研究其对堆芯入口流量分布的影响。结果表明:d对堆芯入口流量没有明显影响,但在中心区域通道,d较小时流量分布更均匀;t减小后,中心区域流体可以更好地向四周扩散,堆芯入口流量分配趋于均匀。

The core inlet flow mal-distribution could lead to a local peak temperature point which is not allowed for the reactor safe operation. The flow skirt was used for a better core inlet flow distribution. In order to study the effect of the flow skirt on the flow distribution, the dimension 'd' on the top of the flow skirt and the length 't' of the support plate were changed for the simulation. The results showed that 'd' had a little effect on the flow distribution, but in the centre area, there was a better distribution with the decreased 'd', if the 't' was smaller, the distribution was more uniform.