中国先进研究堆堆芯流量分配计算

针对中国先进研究堆(CARR)正常运行强迫循环工况和自然循环工况下堆芯内冷却剂流动方向相反的特点,开发了堆芯流量分配计算程序。程序针对这两种运行工况进行了全堆芯的数值模拟,得出堆芯流量分配计算结果和非对称冷却条件下板状燃料元件的温度场。计算发现两种工况下堆芯内各通道的流量份额变化不大,表明流量分配主要取决于通道几何形状和尺寸,基本可以忽略功率分布不均的影响。

The calculation of mass flux distribution of CARR

The CARR is a tank-in-pool and inversed neutron-trap-type reactor with light water used as the primary coolant and moderator and heavy water as the reflector. The fluid flow direction under normal working condition is opposite to that of natural circulation. A multi-channel model steady-state thermal-hydraulic analysis code was thus developed for the calculation of mass flux distribution of CARR under those two conditions. By simulating the whole reactor core, the detailed flow distribution in the core was obtained. Our result showed that the mass flux distribution varied very little for the two conditions. It was also found that the structure size played a most important role in the flow distribution and the influence of the core power could be neglected. The temperature field of fuel element under unsymmetrical cooling condition was also obtained under both conditions.