Numerical Study of the Influence of a Two-Component Gas Mixture Composition on the Properties of a Nanosecond Capillary Discharge

The paper presents a parametric numerical study of a nanosecond capillary discharge in a gas mixture consisting of argon and helium with varying ratio between particle densities of the components. Simulations were performed using a magnetohydrodynamics model with average ion approximation and assuming that local thermodynamic equilibrium is satisfied for electron and ion components of the plasma separately. Parametric analysis revealed that for a given particle density of Ar gas the additional partial pressure of He ions limits the compression of plasma and decreases the resulting peak electron densities, while peak electron temperatures do not vary in a significant manner. The effect in peak electron densities is most dramatic when the Ar : He ratio exceeds 2 : 1.