Accession Number : AD0707883

Title :   HYPERSONIC SURFACE PRESSURE AND HEAT TRANSFER ON SLENDER BODIES IN VARIABLE COMPOSITION AND NONEQUILIBRIUM ATMOSPHERES.

Descriptive Note : Final technical rept. 1 Sep 68-31 Sep 69,

Corporate Author : OHIO STATE UNIV COLUMBUS AERONAUTICAL AND ASTRONAUTICAL RESEARCH LAB

Personal Author(s) : Harney,D. J. ; Petrie,S. L.

Report Date : APR 1970

Pagination or Media Count : 55

Abstract : The aerodynamic testing of slender bodies in high energy wind tunnels is complicated by the effects of the nonequilibrium expansion process in the wind tunnel nozzle. The atmosphere that a model sees varies in composition dependent upon the degree of nonequilibrium. This variation affects the inviscid flow field through changes in the ratio of specific heats and the viscous equations by changes in the transport as well as the thermodynamic properties of the gas. Within the limitations of hypersonic small disturbance theory the inviscid and viscous equations are formulated with a minimal dependence on Mach number and in a way that brings out their explicit dependence on the thermodynamic and transport properties of the gas. The resulting gas property parameters then are calculated for air-argon mixtures, air-helium mixtures, and frozen dissociate air. These parameters appear to provide a realistic estimate of the effect of a variable atmosphere on surface pressure and heat transfer based on the current series of tests on sharp cones and flat plates in air-argon mixtures and in a low pressure arc tunnel. In addition, the present experiments and comparative experiments in other facilities demonstrate a result of more general interest; namely, that the Mach number is not a dominant parameter in slender body viscous hypersonic aerodynamics. (Author)

Descriptors :   (*REENTRY VEHICLES, HYPERSONIC CHARACTERISTICS), AERODYNAMIC HEATING, HEAT TRANSFER, WIND TUNNEL MODELS, PRESSURE, WIND TUNNEL NOZZLES, SLENDER BODIES, VISCOSITY, MATHEMATICAL ANALYSIS

Subject Categories : Guided Missile Reentry Vehicles
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE