Microfluidic Field And Acoustic Radiation Force Of Interaction Between Cavitation Bubbles And Elastic Particles In Ultrasonic Field

With the continuous development of research work,extensive theoretical and experimental studies have been conducted on single bubble,single suspended particle,double bubble and other systems,so that people know that under the action of ultrasound,the acoustic microstreaming and acoustic radiation force generated around bubbles or suspended particles and so on have important practical significance in the fields of biomedicine,life sciences,ultrasonic cleaning,and ultrasonic therapy.The interaction between bubble and bubble will significantly enhance the dynamic response.At the same time,bubble exists as a sound scatterer in the sound field,and the interaction between scattered sound waves and nonlinear vibration may change distribution of acoustic microstreaming and acoustic radiation force around bubble or suspended particles in liquids.Spherical elastic particle is typical particle in the solid particle.Based on this,this paper focuses on the study of acoustic microstreaming and acoustic radiation force generated by the system of elastic particle and bubble,mainly including the following aspects:1.Based on the theory of acoustic waves,the scattering characteristics of rigid particles and elastic particles in an unbounded ideal liquid are studied separately.The expressions of the scattering coefficients in different sound fields are given in detail basis;2.Based on the theory of acoustic scattering and the boundary conditions,in the plane wave sound field,the expressions of the elastic particles with the ideal liquid and the microstreaming around the bubble and elastic particle are derived in detail.Effect of radius?microsphere-to-bubble radius ratio and driving sound frequency are considered on the microstreaming around the bubble and elastic particle.The research results show that the interaction between the elastic particle and bubble significantly enhance the acoustic microstreaming intensity,especially the tangential component.As the interaction between them increase,the velocity of sound flow between particle and bubble decreases.When the two are in a resonance state,the amplitude of the surrounding sound flow velocity is the largest.3.Considering the interaction between elastic particle and bubble,the sound radiation force expression of elastic particle in ideal liquid water in an unbounded plane wave sound field are derived in detail.The variation characteristics of the acoustic radiation force function of a single rigid particle,a single elastic particle,an elastic particle-bubble and a rigid particle-bubble system are analyzed.The elastic radiation force of elastic particle-bubble system is mainly studied by the distance between them and the driving frequency.The change characteristics of the acoustic radiation force function curve show that the acoustic radiation force of elastic particles of different materials all show obvious resonance characteristics,so that a certain peak appears.After considering the effect of the bubble,when ka is small,the acoustic radiation force function appears negative values which pull the elastic particles towards the sound source.As ka increases,the acoustic radiation force function increases to a positive value and tends to a stable value.