高温气冷实验堆堆底流道的热混合性能

Thermal mixing performance of the coolant channel in core bottom of the HTR-10

高温气冷实验堆（ＨＴＲ－１０）堆底流道结构的作用之一是使径向温度分布不均匀的堆芯出口冷却剂得到足够的热混合。在相似模型上进行的试验研究表明，在对应ＨＴＲ－１０正常运行时的冷热气进口流量比为１：０．７４６情况下，堆底流道结构能使冷却剂的温度混合程度和均匀程度分别达９４％和９８．４％以上，再流过热气导管后，即到达热交换器之前，这两个值分别达到９８％和９９．６％。在稍作简化的模型上进行的试验表明，进口流量比对流道的热混合性能影响不大，在进口热冷流量比为０．５～２范围内所得到的温度混合程度在流量比为１时有最大值并在两侧显示出一定对称性的分布，其值在９１％～９５％之间。

To make the outlet coolant of the pebble bed core of the 10 MW HTR-test module (HTR-10) a sufficient thermal mixing is one of functions of the coolant channel in the core bottom reflector. The test on a 1: 1. 5 analogical simulating test module shows that the coolant channel and the hot gas duct of the HTR-10 can yield a non-dimensional coolant temperature mixing degree (Mr) of more than 98% and a temperature homogeneous degree of over 99%. The results of the further test indicate that the influence of the ratio of cold to hot inlet coolant flow rates on the thermal mixing seems light. The value of the Mr varies from 91% to 95%, and then to 91% as the flow rate ratio from 0. 5 to 2. 0, and is symmetrical about the flow rate ratio of 1. 0.