存在内外质量交换的声空化泡动力学模型

对于空化微气泡的动力学研究多基于气泡内外无质量交换的Rayleigh模型。考虑了气泡内外的物质交换,泡内气体分子数量,即气泡平衡半径成为变量,进而将Rayleigh模型推广到有质量交换的情形。通过数值计算,获得稳定平衡半径,以及它与驱动声压的相关性。结果表明:在低声压驱动下,气泡稳定平衡半径随驱动声压增大而减小;而在高声压下,气泡稳定平衡半径随驱动声压增大而增大,稳定平衡半径-声压曲线存在一个转折点。

Dynamical model of acoustic cavitation bubbles with mass exchange

Acoustic cavitation bubble is usually studied within the framework of Rayleigh dynamics without mass-exchange between interior and exterior of the bubble.In this paper,Rayleigh dynamics in the presence of mass-exchange is studied.When mass-exchange is considered,the number of molecules inside the bubble,or the ambient radius,becomes variable at beginning,and gradually reaches a steady state.By numerical calculation,the steady ambient radius together with its dependency on the driving pressure is obtained.The result shows that the steady ambient radius decreases with pressure increasing when pressure is small.It increases with pressure when the pressure gets larger.There is a turning point in the curve of steady ambient radius vs.pressure.