超声对两相液体中分散水滴作用的动力学

Dynamics study on a drop dispersed in two-phase fluid in ultrasonic field

基于空化泡运动方程的推导方法,推导出超声激励下两相液体中分散水滴简化模型的动力学方程,并用MATLAB数值模拟,得出超声作用下不同参量对水滴半径变化的影响。发现对于声速、液体密度及粘滞系数不同的分散相液体,声速对水滴半径变化几乎没影响,液体密度和粘滞系数越小水滴半径增长幅度越大;静压越大水滴体积越不容易变化;水滴初始半径越小水滴半径变化幅度越大。对于确定的分散相液体,超声激励声压幅值越大或激励频率越低,水滴半径变化越大。通过对水滴半径变化的探索,为进一步研究超声对反相乳液作用机理提供理论依据。

In this paper, the equation of motion for spherical water-drop simplified model in dispersed phase liquid under the sonic assistance conditions is given by studying the motion of spherical cavitations bubble. The variation of water-drop radius which is effected by different parameters under the sonic assistance condi- tions were simulated by using the MATLAB. The results show that the ultrasonic wave velocity in deferent dis- persed phase liquid has hardly any effect on the variation of water-drop radius. Smaller values of the density and viscosity factors of deferent dispersed phase liquid means greater amplitudes of variation of water-drop radi- us. The larger the static pressure of the dispersed phase liquid is, the harder the change of water-drop volumes are. The variation of water-drop radius will be big when the water-drop initial radius is small. When dispersed phase liquid is certain, the bigger the amplitude of acoustic or the lower the ultrasonic frequency is, the grea- ter the change of water-drop radius is. It provides a foundation for studying the mechanism of the effects of ul- trasound on inverse emulsion by exploring the change of water-drop radius.