An Experimental Study of Nonstationary Instabilities of Planar Shock Waves in Ionizing Argon

Abstract

A multipulse laser-schlieren technique was used to study the time behaviour of instabilities in the translational front of planar shock waves in ionizing argon in the 10 x 18 cm hypervelocity shock tube at UTIAS. Using a ruby laser in a combined normal-lasing/giant-pulse mode, at least two monochromatic light pulses were obtained about 7 t apart. As well, a schlieren system compatible with the 23 cm dia Mach-Zender interferometer was created with maximum sensitivity for some low-density conditions. The almost-sinusoidal perturbations were found to change with time; some like a standing wave, and others like a travelling wave. It was not, however, possible to associate the observed perturbations with either form of wave motion in nearly half of the cases. A simple graph provides a way to predict the shape of the perturbations from the shock-wave parameters.

Over forty years of continuous research at UTIAS on nonstationary flows and shock waves

“…Analytical and experimental studies on ionizing shock waves and ionizing boundary layers are reported in Brimelow 1974;Tang 1977;Buchanan 1980), and in dusty-gas boundary layers in (Wang and Glass 1986a, 1986c. Additional numerical problems in dusty-gas flows were solved in (Miura and Glass 1982, 1983, 1984, 1985).…”