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

Pulsed discharge in water can generate high-intensity shockwaves 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 shockwave intensity by adjusting the specific internal energy of the plasma. An axisymmetric SPH model is developed to simulate shockwaves generated by the pulsed discharge in water, and the time-history pressure signals of the shockwave are analyzed in detail to investigate its propagation characteristics. The results show that the peak shockwave pressures predicted by the axisymmetric SPH-PIERM model agree closely with experimental measurements, with a mean relative error (MRE) 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 shockwave propagation under complex boundary conditions. This advancement facilitates deeper exploration of the underlying propagation mechanisms of shockwaves generated by pulsed discharge in water.