Non-oscillatory quasineutral fluid model of cross-field discharge plasmas

This paper presents a non-oscillatory quasineutral plasma model, in which the electric field in the ion momentum equation employs the electron drift-diffusion formulation. Due to the quasineutral assumption, the electron pressure is directly coupled with the ion pressure in the inviscid flux of the ion momentum equation, which is solved using a finite-volume method with nonlinear limiting. The electron-pressure coupled method eliminates the grid-scale numerical oscillations that occur particularly near the stagnation point (the ion bulk velocity is close to zero) of a cross-field discharge plasma when using an uncoupled method. Additionally, such numerical oscillations are also observed when using a quasineutral hybrid model where a grid- or particle-based kinetic approach is employed for ions. The importance of coupling the electron pressure and ion momentum in a quasineutral plasma model is discussed.