Simulation of the motion and heating of an irregular plasma

Summary

One of the attractive plasma physics problems is the plasma heating and confinement one. Because of the variety of regimes, the wide range of parameters of the medium, and the complexity and nonlinearity of the examined processes, the problem on plasma heating and propagation is a multiparameter one, which requires the use of various approaches. In the present work the differential model is presented, based on the three-fluid approach, which is designed to perform computational experiments on heating and motion of a dense ionized gas cloud (plasmoid) in a powerful magnetic field. The model takes into account such processes as ionization, heating, heat transmission, and relativist electron beam action. The model includes continuity and energy equations for all plasma components being studied, motion equations for heavy particles, and magnetic-field equations. The action of the electric field is taken into account using the simplifications that allow excluding of relatively rapid electron motions from the calculations, which makes the model more effective.

For the numerical solution of the problem, the economical finite-difference scheme is developed, which is based on the factorization method with the splitting into spatial directions and physical processes. The algorithm allows obtaining solutions of gas dynamics and of magnetic induction equations separately. The beam energy transfer is modeled using the experimental data.

The calculations of the propagation of a plasmoid heated by a source in an external magnetic field are performed. The mechanism of the effect of the magnetic field and of the heat source on the plasmoid expansion is determined.