摇摆条件下小型反应堆堆芯入口流量分配特性数值分析

Numerical Analysis of Flow Distribution Characteristics at Core Inlet of Small Reactor under Rolling Condition

为研究摇摆条件下小型反应堆强迫循环时堆芯入口处冷却剂的流量分配特性,采用数值计算的方法,使用计算流体力学(CFD)软件STAR-CCM+建立小型反应堆模型,完成模型验证,开展摇摆条件下反应堆堆芯入口流量分配特性研究。结果表明,堆芯入口位置距摇摆轴的距离越大,摇摆幅度越大,堆芯入口冷却剂流量波动越大;长周期摇摆对流量影响较小,但随着摇摆周期减小,冷却剂流量会发生跃变。堆芯入口冷却剂分布不均匀程度随摇摆幅度的增加而增加,但对摇摆周期变化并不敏感。

In order to study the flow distribution characteristics of coolant at the inlet of reactor core during forced circulation of small reactor under rolling condition,a small reactor model is established by using CFD software STAR-CCM+with numerical calculation method,model verification is completed,and the flow distribution characteristics at the inlet of reactor core under rolling condition are studied.The results show that the greater the distance from the core inlet to the rolling axis and the greater the rolling amplitude,the greater the coolant flow fluctuation at the core inlet.The long-period rolling has little effect on the flow,but the coolant flow will jump with the decrease of the cycle.The uneven distribution of coolant at the core inlet increases with the increase of rolling angle,but it is not sensitive to the change of rolling cycle.