文丘里式气泡发生器气泡碎化特性研究

熔盐堆在运行过程中须不断地去除氙等气体裂变产物。熔盐堆除气系统中气泡发生器的作用是通过向回路中注入一定量的直径为0.5 mm的小气泡，在扩散作用下吸收熔盐中的氙，最终气泡被分离出来，达到除氙的目的。在橡树岭国家实验室设计的基础上，本文为钍基熔盐研究堆设计气泡发生器，并在专门建造的水回路中对其工作特性进行了可视化研究。利用高速摄像系统跟踪气泡的运动和碎化过程，分析气液相流速对碎化后气泡尺寸的影响。结果表明：在实验条件下，当气体流量一定时，气泡尺寸随液体流量的增大而减小；当液体流量一定时，气泡尺寸随气体流量的增加而增大。

Characteristic of Bubble Breakup in Venturi-type Bubble Generator

During the operation of a molten salt reactor, the continuous removal of gaseous fission product ¹³⁵Xe from the circulating fuel has to be provided. As one of the key devices in the off-gas removal system, the bubble generator is for generating tiny bubbles with average bubble diameter around 0.5 mm. Firstly, certain amount of helium bubbles are injected to the fuel, the bubbles absorb ¹³⁵Xe, and then these bubbles containing ¹³⁵Xe are stripped out of the fuel for removing ¹³⁵Xe in the liquid fuel. In the present study, a new bubble generator was designed for TMSR referenced to the design of ORNL. Meanwhile, a water test loop was fabricated for visualization observation on the performance of the bubble generator. The movement and breakup of the bubbles were recorded by a high speed camera. The effect of gas and liquid flow rates on generated bubble diameter was also analyzed. The results show that under experimental conditions, with the increase of liquid flow rate, the bubble size decreases with the increase of liquid flow rate when the gas flow rate remains unchanged; the bubble size increases with the gas flow rate when the liquid flow rate is constant.