高温堆双区堆芯交混区内球分布实验研究

Experimental study of the pebble distribution in the mixing zone of a two-region HTGR reactor core

双区堆芯的设计代表了高温气冷堆技术的发展方向之一。为确定高温气冷堆双区堆芯交混区内燃料球分布情况开展实验研究,解决与高温堆堆芯结构和物理设计密切相关的问题。实验结果表明:交混区内燃料球和石墨球的概率分布具有良好的对称性;堆芯上部的交混区内燃料球分散度较小,中部较大,交混区并没有无限扩散而具有确定的范围,说明球流运动是一种有限的分散性;在加球面上加入任一球其在交混区内的概率密度分布满足Gauss分布规律;根据Gauss分布对称中心可以确定交混区内球流均值流线并从理论上确定交混区大小。

The two-region reactor core is a key part of the high temperature gas-cooled reactor （HTGR） design. The pebble distribution in the mixing zone of a two-region HTC-R reactor core was studied experimentally to understand the effects of the reactor core structure and physics. The results indicate that the probability distributions of fuel and graphite pebbles show an obviously symmetrical characteristic in the mixing zone with fuel pebbles mainly scattered in the middle part of the reactor core and with the distribution of pebbles added on the surface in the mixing zone being Gaussian distribution. The mean streamline of pebbles in the mixing zone can be determined according to the center of Gaussian distribution to obtain the size of the mixing zone in theory.