Date of Award
Master of Science
Department of Engineering Physics
William F. Bailey, PhD
An analysis and assessment of two mechanisms in plasma shock interactions was conducted under conditions typically encountered in a weakly ionized glow discharge. The mechanisms of a spatially-dependent electron temperature and additional electron impact ionization at the shock front were examined for effects on shock structure and propagation. These mechanisms were incorporated into an existing one-dimensional, time-dependent, fluid dynamics code that uses the Riemami problem as a basis and numerically solves the Euler equations for two fluids: the neutral gas and the charged component. The spatial variation in electron temperature was modeled as a shock-centered rise in temperature. Additional ionization was modeled by incorporating a variable electron temperature and a quasi-kinetic collision function, for both unrestricted ionization and ionization mitigated by ion-electron recombination. Introduction of a spatial variation in electron temperature resulted in a broadening and strengthening of the electric field associated with the electronic double layer (EDL) at the shock front. Results of unrestricted ionization were a broadening and strengthening of the electric field associated with the EDL, acceleration of the neutral shock front, and the development of a neutral precursor ahead of the shock. Ion-electron recombination was seen to reduce these effects.
DTIC Accession Number
Walker, Shannon L., "Double Layer Effects on Shock Wave Propagation" (1999). Theses and Dissertations. 5183.