Evaluation of assumptions and criteria in pseudostationary oblique shockwave reflections
Abstract
The assumptions and criteria in the treatment of oblique shockwave reflections with two and threeshock theories are critically assessed. Experimental results for N2 and Ar by BenDor (1978) and CO2 by Ando (1981) and recent results for air (Deschambault, 1984) and SF6 (Hu, 1985) are used to: (1) clarify the effects of excitation of the internal degrees of freedom; (2) evaluate the deviation from the assumption that the Mach stem from the triple point is perpendicular to the wedge surface; and (3) improve the agreement in the transition boundaries between experiment and analysis. Analysis of recent experimental results together with numerical calculations revealed the following: (1) the transition Mach number at which the reflection pattern changes from a frozen to an equilibriumgas flow can be ascertained from a comparison of the relaxation length of the internal degree of freedom of the gas and a characteristic length of the flow; and (2) the deviation of the experimental orientation of the Mach stem at the triple point from perpendicularity to the wedge surface is fairly significant.
 Publication:

Proceedings of the Royal Society of London Series A
 Pub Date:
 July 1986
 DOI:
 10.1098/rspa.1986.0065
 Bibcode:
 1986RSPSA.406...75S
 Keywords:

 Gas Dynamics;
 Oblique Shock Waves;
 Shock Wave Interaction;
 Wave Reflection;
 Boundary Layer Flow;
 Computational Fluid Dynamics;
 Degrees Of Freedom;
 Flow Measurement;
 Incidence;
 Mach Reflection;
 Shock Wave Attenuation;
 Wedge Flow;
 Fluid Mechanics and Heat Transfer