Accession Number : AD0669131

Title :   ON RADIATIVE TRANSFER IN THE LOW REYNOLDS NUMBER BLUNT BODY STAGNATION REGION AT HYPERSONIC SPEEDS. PART I. EMISSION DOMINATED CASE.

Descriptive Note : Technical rept.,

Corporate Author : BROWN UNIV PROVIDENCE R I DIV OF ENGINEERING

Personal Author(s) : Liu,Joseph T. C.

Report Date : MAR 1968

Pagination or Media Count : 38

Abstract : One objective of the paper is to contribute to an understanding of radiative transfer effects in the low Reynolds number or merged layer regime of hypersonic flow about axisymmetric blunt bodies. The other objective is to illustrate how the concept of thin shock layer theory can be extended to the radiative case, where the shock structure and shock layer are radiatively coupled, through the introduction of a psuedo-jump condition across the shock structure, accompanied by an iteration technique. The radiative transfer is simplified to the emission dominated case. The gas is taken as calorically and thermally perfect, the viscosity taken as a linear function of the temperature, and the absorption coefficient of the gas is assumed to be gray. The problem is formulated for the flow about a blunt body but the detailed calculations are carried out for the stagnation region in order to illustrate the techniques used. Radiative cooling decreases the convective heat transfer from the corresponding radiationless case. The additional contributions to the heat transfer due to radiative transfer come from both the shock structure and the shock layer. The relative importance of these contributions are assessed in terms of the rarefaction parameter. Radiative contributions become less important toward the free-molecular range. Radiative cooling decreases the overall shock structure and shock layer thicknesses. (Author)

Descriptors :   (*THERMAL RADIATION, HYPERSONIC FLOW), REYNOLDS NUMBER, BLUNT BODIES, STAGNATION POINT, EMISSIVITY, VISCOSITY, COOLING, THERMODYNAMICS, ABSORPTION, HEAT TRANSFER

Subject Categories : Aerodynamics
      Fluid Mechanics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE