An Experimental Investigation of Normal Shock Wave Velocity Distribution Functions in Mixtures of Argon and Helium

摘要

The electron beam-spectroscopic technique developed by Muntz for measuring simple one-dimensional moments of helium velocity distribution functions was extended for use with argon. Measurements were made on argon-helium gas mixture normal shock waves at low Mach numbers. Intensity versus wavelength profiles of single spectral lines for each gas were determined at fixed points within the shock waves with a Fabry-Perot interferometer. Lines of sight both perpendicular and parallel to the flow direction were chosen. By using appropriate calibration functions, the effect of Doppler broadening on the line structure was isolated from all other sources of line broadening, and in this way curves of parallel and perpendicular temperature for each gas as functions of position were constructed. Macroscopic velocities were measured by determining the blue shift in the line profiles when the line of sight shifted from the perpendicular to the parallel direction. The data thus obtained provided detailed information on the variation of species velocities and parallel and perpendicular temperatures within the shock waves. These results were then compared with existing theories and other experimental results. (Author)