Design And Optimization Of The High Power Electromagnetic Shock Wave Generator

The high power electromagnetic shock wave generator is made by the shock action of strong pulsed magnetic field of microsecond duration on thin membrane,which is in contact with the sound medium.It is widely used in clinical extracorporeal lithotripsy,deep geological exploration,industrial cleaning,vacuum packaging detection and so on.At present,the development of high power output electromagnetic shock wave generator in China,compared to foreign research,is still at a relatively low level,some important equipment in some important areas still need to be imported.Therefore,it is very necessary to actively carry out in-depth research on the key technology in this field.The research work focuses on using finite element method to get the electromagnetic shock wave generator optimized in order to obtain an electromagnetic shock wave generator with high efficiency and high power output.A multi-physics modeling of the electromagnetic shock wave generator is carried out on the finite element simulation software COMSOL Multiphysics.And compared with the basic principle of the electromagnetic shock wave generator,the correctness of the model and the effectiveness of finite element simulation software in the design of electromagnetic shock wave generator are verified.The electromagnetic shock wave generator system is analyzed in this thesis.And it is explained from three aspects of transducer vibration components,excitation circuit and sound field characteristics in detail.The interaction between operating frequency,output power and electro-acoustic conversion efficiency is studied.The influence factors of the eigenfrequency of metal vibration membrane and the influence of different membrane physical parameters on the deformation characteristics are given through the modeling.The concept of the largest point of membrane deformation is proposed.And combining with the equivalent model of the excitation circuit,the theoretical parameters of the excitation circuit are optimized.The acoustic field of the electromagnetic shock wave generator is preliminarily simulated and analyzed.An optimum structural design of the membrane of the electromagnetic shock wave generator is presented in this thesis.Firstly,the performation of three type of membrane is compared and discussed based on the simulation results,the conclusion is obtained that the corrugated membrane has the largest amplitude under the same excitation.And then the influences of the corrugated thickness,corrugated height,the number of wave and the corrugated shape on the deformation of the corrugated membrane under the excited coil are discussed in detail.The optimal design parameters of the corrugated membrane are obtained by the results of simulation.Finally,the actual design of the membrane used in the electromagnetic ultrasonic shock wave generator is introduced,a simulation APP is developed to speed up the design progress of electromagnetic shock wave generator.