上升气泡内气溶胶沉降机理研究

气溶胶池洗过滤是反应堆严重事故中去除放射性源项的重要手段。本文以严重事故条件下上升气泡中气溶胶的滞留过程为背景，设计搭建了可视化单气泡鼓泡实验装置。通过该装置研究了气溶胶在上升气泡中的沉降效率，并与MELCOR中的气溶胶沉降模型计算结果进行了对比。结果表明，气溶胶沉降效率对气泡尺寸的变化较为敏感，当气体流量大于0.1 L/min时，气泡等效直径迅速增加，相应的气溶胶沉降效率快速降低；与MELCOR模型计算结果的对比表明，两者在总体趋势上呈现出较好的一致性，但计算结果低估了液相对气溶胶的实际去除能力，导致这种偏差的主要原因是气泡在上升过程中存在无规则的晃动以及气液界面的波动。

Research on Mechanism of Aerosol Deposition in Rising Bubbles

The aerosol pool scrubbing process is an important method to remove the radioactive source term in serious reactor accidents. Based on the aerosol retention process in the rising bubble under the condition of serious accident, a visual single bubble bubbling experiment was designed and constructed. Through this device, the deposition efficiency of aerosol in rising bubbles was studied. It is found that aerosol deposition efficiency is sensitive to the change of bubble size. When the gas flow rate is greater than 0.1 L/min, the bubble equivalent diameter increases rapidly, and the corresponding aerosol deposition efficiency decreases rapidly. The experimental results were compared with the results calculated by the MELCOR model, which shows a good consistency in the overall trend. However, the calculation results significantly underestimate the actual removal ability of liquid to aerosols, which is mainly caused by the irregular shaking of bubbles during the rising process and the fluctuation of gas-liquid interface.