A Simulation Study On CRN Electrode Characteristics Of Plasma Impulse Sound Source

The shock wave generated by the impulsive sound source is widely used in the fields of in vitro rock crushing,liquid electric sand removal,rock crushing and sewage treatment.In the realm of acoustic depth detection,the use of impulsive sound sources can effectively compensate for the drawbacks of numerous existing acoustic logging approaches in terms of detection depth and detection resolution.Several elements influence the performance of the impulsive sound source,including circuit characteristics,water parameters,electrode shape,and so on.Studying the mechanism of the high current pulse discharge process in water,analyzing the effect of external conditions on the electroacoustic characteristics of the impulsive sound source,and optimizing the discharge electrode structure can provide a foundation for the design of the impulsive sound source.In this study,the impulsive discharge plasma control equation is constructed to explain the discharge process,and the energy conversion process is analyzed by analyzing the mechanism and discharge process of shock wave generated by high current impulse discharge process in water.The computation can yield the intensity of the shock wave,the excitation wave conversion efficiency,and the electro-acoustic conversion efficiency.The same needle-needle electrode configuration as in the classical experiment is built in the finite element simulation program COMSOL,and the impulse excitation wave intensity generated during the discharge process is derived by solving the pulse discharge plasma control equation.The results reveal that the numerical simulation results are similar to the conventional experimental results,proving the numerical simulation method’s soundness.For the effect of different electrode structures on the electroacoustic properties of the impulsive sound source,the cone-ring electrode(C-type electrode),rod-ring electrode(R-type electrode),and needle-ball electrode(N-type electrode)models were constructed.The electroacoustic properties of C,R,and N electrodes were studied with varying electrode spacing and constant external circuit parameters.Because the R-type electrode has a greater shock wave intensity and electroacoustic conversion efficiency,it is chosen as the preferable electrode with an electrode gap of 8 mm.The impacts of external factors on the electroacoustic features of the impulsive source were studied by investigating the effects of the charging voltage,ring electrode radius,and aqueous medium temperature on the electroacoustic characteristics of the R-type impulsive source.The results reveal that when the charging voltage increases,the prebreakdown time lowers,and the shock wave intensity and electroacoustic conversion efficiency improvements,while the electroacoustic conversion efficiency drops after 16 k V.With a ring electrode radius of 4 mm,the peak impulse intensity,excitation conversion efficiency,and electroacoustic conversion efficiency were optimum.Peak impulse intensity,excitation conversion efficiency,and electroacoustic conversion efficiency all rise with rising aqueous medium temperature,but the increase is modest.The findings revealed that the improved impulsive sound source’s pre-breakdown time was reduced,the peak impulse intensity rose by4.05% from 3.70 MPa to 3.85 MPa,and the electroacoustic conversion efficiency increased from 4.67% to 5.00%,making it more suited as the source.