A simplified 2-D fluid model of plasma formation under pulsed high power microwaves in atmospheric gases

The mechanism of plasma formation under high power pulse (HPM) excitation in gases (nitrogen and argon) at atmospheric pressures is studied utilizing a fluid model verified against experimental data. A 2-D approximation was introduced to model the cylindrically shaped gas volume and the associated electric fields. Thus, the fluid equations and Poisson equation for space charge effects are updated in x and y directions only (setting the gradient in the z-direction to 0). The goal of this numerical simulation was to accurately predict the plasma formation delay time under different gas types and pressures based on the calculated evolution of the plasma conductivity.