单泡超声空化仿真模型的建立及其动力学过程模拟*

为了模拟单泡超声空化的动力学特性,建立了单泡超声空化的有限元仿真模型,基于流体动力学控制方程和流体体积分数模型,利用有限元分析软件模拟了超声驱动下水中单泡的空化动力学过程。结果表明:单泡随时间的演化规律是先缓慢膨胀到最大后迅速塌缩;泡内压强与气体密度变化与单泡体积变化成反比;在膨胀阶段,泡外压强与气体密度沿着泡的径向向外递减;在压缩阶段,泡外在声压垂直方向的压强与气体密度要大于声压激励方向的压强和气体密度。该文分析结果将为超声空化动力学过程模拟及研究提供参考。

Establishment of a single-bubble ultrasonic cavitation simulation model and simulation of its dynamic process

In order to simulate the dynamic characteristics of single bubble ultrasonic cavitation, a simulation model of single-bubble ultrasonic cavitation was established. Based on the fluid dynamics control equation and volume of fluid model, the finite element analysis software was used to calculate the cavitation dynamic process of a single-bubble in water driven by ultrasound. The results show that the evolution rule of a single-bubble with time is that it expands slowly to the maximum and then collapses rapidly. The change of the pressure and the gas density inside the bubble is inversely proportional to the change of the single bubble volume. In the expansion phase, the external pressure and the gas density of the bubble decrease along the radial direction of the bubble. In the compression phase, the pressure and gas density in the vertical direction of sound pressure are greater than that in the direction of sound pressure excitation. The results in this paper will provide a reference for simulation of the dynamic process of the ultrasonic cavitation.