Current Applied Physics, Vol.18, No.10, 1101-1107, 2018
Modeling of the initial stages of the formation of heterogeneous plasma flows in the electric explosion of conductors
The experimental and theoretical studies on scattering of electric explosion products in the end-type plasma accelerator are carried out. Using the method of high-speed imaging (106 shots per second), it is revealed that there are three zones in a heterogeneous plasma flow. Zone 1 is a plasma focus, in Zone 2 there is a 90 degrees turn of a flow, whereas a plasma flow is parallel to the dielectric disk in Zone 3. Following the concepts of plasma scattering when exposed to magnetic and gas-dynamic pressure, a mathematical model is proposed and provides an adequate explanation of plasma motion in Zone 3. It comprises equations of laws of mass and conservation of momentum, as well as the first and second Kirchhoff s laws. The outcomes of modeling are in compliance with the experimental data. A numerical single-fluid magnetohydrodynamic model is developed for general description of formation and evolution of a plasma flow. It is based on Navier-Stokes and Maxwell's equations. The obtained patterns of plasma current distribution agree satisfactory with the results of high-speed imaging. They point at a jet in the central part of the electrode, which splits out with the distance from its surface.
Keywords:Electric explosion of conductors;Heterogeneous plasma fluxes;Finite element method;Conservation laws