Transport processes in plasma with an admixture of several heavy impurities
- PDF / 561,504 Bytes
- 17 Pages / 612 x 792 pts (letter) Page_size
- 52 Downloads / 168 Views
MA DYNAMICS
Transport Processes in Plasma with an Admixture of Several Heavy Impurities I. V. Fomina, b*, N. A. Bobrovaa, and P. V. Sasorova a Keldysh
Institute of Applied Mathematics, Russian Academy of Sciences, Moscow, 125047 Russia Institute of Physics and Technology, Dolgoprudnyi, Moscow oblast, 141700 Russia *e-mail: [email protected]
b Moscow
Received September 30, 2016; in final form, November 30, 2016
Abstract—A two-temperature magnetohydrodynamic model of an ideal, fully ionized magnetized plasma consisting of electrons and several types of ions is developed for the case in which the mass of ions of the first type is much lower than that of j th-type ions, where j = 2, 3, …, m1 ! m j , while the densities of heavy ions are so low that collisions between them can be neglected. The ion component is assigned a common velocity, common temperature, and common density, while its composition can vary in time and space. DOI: 10.1134/S1063780X17060058
1. INTRODUCTION Collisional plasma consisting of electrons and one type of ions is usually described within a magnetohydrodynamic (MHD) model with a self-consistent electromagnetic field. The model is based on general kinetic equations for the single-particle distribution functions of both plasma components. Being derived from kinetic equations, the dissipative effects are rigorously substantiated. These issues are most completely described in the famous works by S.I. Braginskii [1, 2]. However, when modeling collisional plasma dynamics, it is often necessary to take into account that plasma consists of several types of multicharged ions. Indeed, natural and laboratory plasmas often have a complex chemical composition. In addition to electrons, it contains ions of different mass and/or charge. This fact is usually ignored in numerical simulations of plasma processes. However, ions with different masses and charges may behave differently and their number densities can depend on the coordinates and time in a different way. The problem of adequate description of collisional plasma consisting of several types of ions is highly challenging. The influence of impurities on dissipative fluxes was discussed in [3–12]. For instance, Vekshtein [3] analyzed the diffusion of impurities in plasma near the chamber walls. The one-fluid one-temperature MHD equations for plasma of complex chemical composition were derived in [4] from the general principles of weakly nonequilibrium statistical physics. These equations describe diffusion of different chemical components and take into account the contributions of the gradients of the chemical composition to the electron−ion friction force and the heat fl ux. The
electron part of the two-temperature MHD equations for plasma of complex chemical composition was also derived in [4]. To investigate diffusion in plasma of complex chemical composition, Gordeev [5] used a three-fluid approximation for relatively cold plasma. The complete system of hydrodynamic equations describing plasma consisting of electrons and two types of ions was d
Data Loading...
