Numerical simulation of shock waves from pulsed discharge in water based on the SPH-PIERM

Pulsed discharge in water can generate high-intensity shock waves with complex propagation characteristics, and existing methods struggle to accurately analyze their dynamic evolution. The Smoothed Particle Hydrodynamics (SPH) method, owing to its high accuracy and strong robustness, has become an effective tool for investigating such problems. To address the insufficient accuracy of the explosive-equivalent approach in SPH-based numerical simulations of pulsed discharge in water, this paper proposes the Plasma Internal Energy Regulation Method (PIERM). This method neglects variations in plasma mass under different discharge conditions and instead precisely controls shock wave intensity by adjusting the specific internal energy of the plasma. An axisymmetric SPH model is developed to simulate shock waves generated by the pulsed discharge in water, and the time-history pressure signals of the shock wave are analyzed in detail to investigate its propagation characteristics. The results show that the peak shock wave pressures predicted by the axisymmetric SPH-PIERM model agree closely with experimental measurements, with an average relative error of less than 2%. Moreover, the model successfully captures key physical features such as wall-reflected waves and rarefaction waves from the free liquid surface, demonstrating its capability to accurately represent shock wave propagation under complex boundary conditions. This advancement facilitates deeper exploration of the underlying propagation mechanisms of shock waves generated by pulsed discharge in water.