Theoretical computation of the electrical conductivity of thermal plasmas-application to plasma torch design of an electrothermal launcher

Abstract

Designing a plasma torch that allows the ignition of gun propellant is generally complex. In this paper, however, we show that it is possible to design a torch from using simplified calculation of electrical conductivity with the help of an experienced design method (Doehlert matrix). First, we explain how to obtain plasma composition both at and out of thermal equilibrium. Then, we compare the simplified calculation with the complete calculation of electrical conductivity. Then, we construct a Doehlert matrix as a function of temperature and thermal nonequilibrium. Finally, we study the length/diameter ratio versus the length and resistivit

Convection effect on an arc plasma evolution process in a two parallel contact system

“…The time-varying electromagnetic field induced by the current loop, including the electrodes and arc column, is calculated in this paper. Therefore, compared with most of the previous studies [5][6][7][8][9][10][11][12][13], the item…”

“…They also calculated the air and different metal vapor mixture plasma properties. Ander et al [4,5] and Zhang et al [6] calculated the composition and thermodynamic properties of ablated vapors of Cu, PMMA, PA6-6, PETP, POM and PE. In addition, the modeling of the plasma-sheath boundary region and the influence of the surface structure on arc voltage were studied [7,8].…”

Numerical simulation of capillary plasma flow generated by high-current pulsed power

“…In Fig. 3(b), present calculation of electrical conductivity at the standard atmospheric pressure is compared with the computation of André and Brunet [15], who included more complex species such as C 2 , H 2 , CH 2 , C 2 H, C 2 H 2 , etc., in their thermodynamic property formulations. Those diatomic and polyatomic species become important at relatively low temperature of less than 5000 K and the comparison shows the discrepancy is noticeable only below 5000 K. Therefore, simplified approach of only including monoatomic species could be acceptable in providing reasonably accurate transport properties to present computations of typical plasma conditions in ETC gun operations.…”

“…Symbols represent the computational results by André and Brunet[15] and solid lines are from present calculations.…”