Spark model of pulsed discharge in water

Underwater sparks have long been used in many fields, but up until now there are no widely accepted model for them. In this article we present a more practical model for them, taking into account the nature of the plasma of pulsed discharge in water, where the following corrections are included: (1) correction of the ionization potentials; (2) pressure caused by the effect of charge interaction on the bound state electrons; (3) line spectra; and (4) mass flow caused by evaporation, condensation, and bubble wall ablation. Using this model, the time-varying pressure, temperature, and density can be obtained for given circuit parameters. The simulation results are in good agreement with the experimental measurements. We also give a simulation with capacitance of 1.25 nF, initial voltage of 4×104V, circuit inherent inductance of 20 nH, and circuit resistance of 15 m; the maxima of the pressure, temperature, and electron density are about 5×104K, 5×10 3atm, and 4×1026m-3, respectively. © 2002 American Institute of Physics.