On plasma jet formation in vacuum arc with composite cathode

Abstract

This paper deals with the computer modeling of vacuum arc with composite multicomponent cathode. This arc is typical for certain kind of ion sources, plasma generator and vacuum interrupters. The described hybrid model treats the electrons as an inertialess fluid and ions as macroparticles. The macroparticle dynamic is calculated with the use of particle-incell method. Ion-ion Coulomb collision is considered with the use of Monte Carlo method. The model can simulate vacuum arc as a whole including separate cathode plasma jets, mixing zone, and common plasma column. The dependence of ion angular current distribution on the cathode composition reproduced with the help of developed model agrees well with experimental results.

Hybrid MHD/PIC simulation of a deuterium gas puff z pinch

“…Ion-ion Coulomb collision is considered with the use of MC method. In the model simulation, in the configuration close to described in [6], it was obtained the neutron yields up to 1.2×10 12 . Most neutrons are not thermonuclear.…”

“…According to the hybrid approach the electron subsystem is described as an inertialess fluid, but ions are described as macroparticles. The developed model is analogous to the model [11,12], but the described model is modified to account for the deuterium ionization and neutron production due to DD fusion. The governing equations in case of the 2D axial symmetrical geometry are the following: …”

“…Recent experiments [6,7] made in a novel configuration have shown that the neutron yields can reach 3.6×10 12 at current about of 3 MA. Earlier, this neutron yield could be surpassed only on the 15-MA pinch.…”

Magnetised and unmagnetized axisymmetric particle-in-cell simulations of ion energy distributions in cathodic vacuum arcs

“…The simulation of dense energetic plasmas, including arcs, is active research area. Attempts have been made to accurately capture the complex dynamics of vacuum arcs using magnetohydrodynamic (MHD) simulations [12,13] and of individual cathode spots using test-particle simulations [12,[14][15][16][17][18]. Full particle-in-cell (PIC) simulations are kinetic, so they can be used to study the development and properties of non-Maxwellian distributions (a limitation of MHD simulations).…”

“…2D axisymmetric hybrid simulations of the ion dynamics at the cathode surface with and without an applied axial magnetic field were performed by Shmelev et al [17,21]. These simulations used a magnetised fluid model for electrons and a PIC model for ions and neutrals, to investigate the structure of the plasma jet from a vacuum arc spot.…”