On the thermal Rayleigh problem in partially ionized argon
Abstract
A complete set of equations providing a macroscopic description of the thermal Rayleigh problem for a partially ionized plasma is derived from the Boltzmann equation and rate equations for ionization and recombination. The plasma properties and boundarylayer nature of the problem are approximated, the set of resulting equations is written in dimensionless form in Lagrangiansimilarity coordinates, and boundary conditions are specified at the outer edge of the boundary layer and at the shocktube wall, taking the influence of the electric sheath near the wall into account. Transport and relaxation phenomena are considered, the equations are solved numerically by a finitedifference technique, and the accuracy of the solutions is evaluated. A diagnostic technique is described whereby a twowavelength laser schlieren device is used to study partially ionized gases produced by reflection of a shock wave having an incident Mach number of 7 to 10 and an initial pressure of 5 torr from the cold end wall of a shock tube. Experimental results obtained for argon are compared with the numerical solutions to the theoretical model.
 Publication:

Ph.D. Thesis
 Pub Date:
 1976
 Bibcode:
 1976PhDT........22H
 Keywords:

 Argon Plasma;
 Boundary Layer Plasmas;
 Plasma Physics;
 Rayleigh Equations;
 Thermal Boundary Layer;
 Boundary Conditions;
 Boundary Layer Equations;
 Finite Difference Theory;
 Gas Ionization;
 Ionization Cross Sections;
 Plasma Diagnostics;
 RankineHugoniot Relation;
 Refractivity;
 Schlieren Photography;
 Shock Tubes;
 Transport Properties;
 Plasma Physics