PWR堆中非均匀余弦加热的传热研究

STUDYING OF HEAT TRANSFER ON VERTICAL NONUNIFORM COSINE HEATING IN PWR

在非均匀余弦加热、低压（≤4×105Pa）和中速（≤2.6m/s）向上流工质水中,通过试验和数值计算垂直圆管内外壁温度场来确定过冷沸腾空泡起始点。研究结果表明:空泡起始点首先出现在余弦曲线中心,并随着加热功率的增加和流量的减少向人口推进。在一个中压水回路上,用一个电磁阀模拟PWR的LOCA工况,实验测得CHF出现的时间tCHF和事故下压力、流量、流体温度以及内外壁温度的变化参数,并对这些参数进行了分析研究。

The determination of the point of onset of significant void (OSV) hasbeen completed by the experiment and computing the temperature field of vertical tube wall in the up-flow boiling of water at nonuniform heat of co- sine distribution, low pressure (<4bar) and middle velocities (<2.Sm/s). The results show that the point of OSV firstly emerges from the top of cosine curve and goes to the tube inlet as the beating power increases and flow rate decreases, The blowdown test with simulated nonuniform heating of the reactor core element in the inlet break condition was carried out in the middle pressure water loop. An electromagnetic valve was used as a break. The time from the start of blowdown to the onset of critical heat flux (CHF), and the pressure, flow rate, fluid temperature in the blowdown process were measured. The analysis of these parameters is also given.