Accession Number : AD0264494

Title :   A THEORY OF ENTROPY LAYERS AND NOSE BLUNTNESS IN HYPERSONIC FLOW

Corporate Author : STANFORD UNIV CALIF

Personal Author(s) : YAKURA,JAMES K.

Report Date : JUL 1961

Pagination or Media Count : 1

Abstract : The method of inner and outer expansions was used in obtaining uniforml -valid solutions far downstream from the blunt nose of slender bodies in hypersonic flow. Application of this technique on the inverse problem, which prescribes the shock wave leaving the body to e determined, results in a unique treatment of the flow field. The influence of nose (shock) bluntness on the flow field and body shape is found to be significant due to the formation of a layer of low density, high entropy air enveloping the body. This entropy layer i in many respects analogous to Prandtl's viscous boundary layer. Analytical solutions, which assume an inviscid perfect gas and infinite Mach number were obtained for hyperbolic and power-law shock wave shapes. The hyperbolic shocks correspond to flows past bl nted wedges and cones in two an three dimensions, respectively. The second-order result for these two case yield a displacement thickness due to t e entropy layer. The lunt body that produces a paraboloidal shock is found to grow as a small power of the distance. (Author)

Descriptors :   *BLUNT BODIES, *ENTROPY, *HYPERSONIC FLOW, BOUNDARY LAYER, CONICAL BODIES, GASES, HYPERSONIC CHARACTERISTICS, MACH NUMBER, SHOCK WAVES, THEORY, WEDGES

Distribution Statement : APPROVED FOR PUBLIC RELEASE