Simulations of gas-dynamic flows during streamers propagation at liquid dielectrics breakdowns

For the case of selfsimilar solution for the problem of streamer channel expansion at the electric breakdown in liquid, computations using the lattice gas (LG) and lattice Boltzmann equation (LEE) methods were carried out. In the latter case, the computation results agree well with theoretical calculations. Computations of the prebreakdown stage of the propagation of a rectilinear streamer channel were also carried out. Expansion of the conductive channel and formation of compression waves propagating with a speed close to the sound velocity in a dielectric liquid were observed. The stochastic evolution of the streamer structure was computed with allowance for the gas-dynamic flows. In this case, the growth proceeds due to both the hydrodynamic movement of the conductive phase and the breakdown of new portions of the substance. Transition between two mechanisms of development of the conductive structure was demonstrated