【摘要】 文丘里式气泡发生器因其结构简单、能够有效产生所需均匀粒径的微气泡等优点,被熔盐堆脱气系统所采用。本文在脱气回路水力试验台架的实验基础上,借助高速相机来研究气泡在文丘里气泡发生器喉部和扩张段处的运动和碎化特性。研究表明:气泡运动可以分为4个阶段:1)气泡高速稳定运动阶段;2)气泡速度剧烈变化阶段;3)气泡速度稳定波动阶段;4)气泡低速稳定运动阶段。随着进气孔径的增大气泡在上述4个阶段的稳定性增加;随着水流量的增加,第二和第三阶段的区域将会向靠近x=0 mm处缩小。其中气泡的碎化过程主要是在第二阶段发生的。更多还原

【Abstract】 [Background] The Venturi-type bubble generator is adopted in molten salt reactor degassing system because of its advantages of simple structure and effective production of micro-sized bubbles. [Purpose] This study aims to investigate the motion and breakup characteristics of bubbles in the throat and expansion section of Venturi-type bubble generator. [Methods] Based on the experimental water loop, high speed camera was employed to measure the movement of bubbles. The velocity distribution of bubbles in the throat and expansion section were analyzed, and compared with water velocity distribution without gas inlet. [Results] Bubble motion was divided into four stages: high-speed stable motion stage; rapid change stage; stable fluctuation stage; low-speed steady motion stage. With the increase of the gas inlet diameter, the fragmentation rate of the bubble decreases, and the stability of the bubble increases in the above four stages. As the water flow increases, the areas in the second and third stages will shrink to near x=0 mm. [Conclusion] The fragmentation of bubbles is related to the distribution of bubbles in the throat and expansion section of Venture-type bubble generator. The higher the velocity of the bubble changes, the greater the degree of fragmentation of the bubble, and the breakup process of bubbles occurs mainly in the second stage.更多还原