An analytical solution of the problem on the plasma piston expansion in equilibrium gas and liquid medium

Summary form only given. In the problem of radiation and propagation of acousto-hydrodynamical perturbations in gas and liquid media affected by pulse sources such as electrical explosion, optical breakdown etc., the necessity of solving the outer hydrodynamic problem appears. If the liquid contains small gas bubbles, that can be observed under real conditions, it is possible to neglect the transient processes of the medium density regulation and to use the description based on the medium equilibrium. This allows essentially simplifying the mathematical statement for description of the above mentioned processes. In this paper a self-similar solution for an uniformly moving cylindrical piston in equilibrium gas and liquid medium is presented. The obtained analytical dependence of pressure at the piston on the velocity of its expansion and volume gas content can be used for description of quasiuniform channel expansion under the active stage of the electrical explosion in a liquid containing small gas bubbles.