液体中气泡运动行为研究进展

Research progress on bubble motion behavior in liquids

对气泡在液层中的单气泡运动行为和气泡群运动行为进行了综述。通过借助高速摄像机、粒子图像测速技术PIV以及数值计算等方法对气泡运动行为进行了研究。结果表明:液体性质、气泡尺寸、气泡尾部涡旋等多种因素导致气泡在液层中呈现出直线形、螺旋形、“之”字形等不同的上升路径;压力、进气量、液体性质等因素导致气泡形状发生变化;上升速度、液体湍动程度、黏性剪切力、浮力等作用力的影响会使气泡行为表现为聚并、碰撞和破碎。但当前研究对气泡内部运动、传质机理以及气泡群的关注较少,今后可通过对泡内流体行为、气泡群之间的相互作用、影响因素进行分析来完善传质机理。从介观尺度角度开展强化传质,可通过添加破泡内构件对大气泡进行强制破碎,减小其气泡尺寸,增大传质面积和停留时间以达到强化传质的目的。

A review is conducted on the single bubble motion behavior and bubble group motion behavior of bubbles in the liquid layer.The bubble motion behavior is studied using high-speed cameras,particle image velocimetry technique(PIV),and numerical calculations.The results show that factors such as liquid properties,bubble size,bubble tail vortex lead to different upward paths of bubbles in the liquid layer showing straight,spiral,and zigzag shapes;factors such as pressure,inlet volume,and liquid properties cause changes in the shape of bubbles;the effect of the upward velocity,the degree of liquid turbulence,viscous shear force,buoyancy and other forces will manifest the bubble behavior as aggregation,collision and fragmentation.The existing studies pay less attention to the internal motion of bubbles,the mass transfer mechanism and bubble groups.In the future,the mass transfer mechanism can be improved by analyzing the fluid behavior inside bubbles,the interactions between bubble groups,and influencing factors.Strengthening mass transfer at the mesoscale can be achieved by adding bubble-breaking internal components to forcibly break large bubbles,reducing the bubble size,increasing mass transfer area and residence time,in order to enhance mass transfer.