Accession Number : AD0262625

Title :   BOUNDARY LAYER DEVELOPMENT IN SUPERSONIC SHEAR FLOW

Corporate Author : ADVISORY GROUP FOR AERONAUTICAL RESEARCH AND DEVELOPMENT PARIS (FRANCE)

Personal Author(s) : ROGERS, RUTH H.

Report Date : APR 1960

Pagination or Media Count : 30

Abstract : The development of the boundary layer on the surface of a blunt cone has been investigated. Experimental results are presented for cones having a 15 degree included angle and a tip radius varying from less than a thousandth of an inch to about half an inch. The cones were placed in streams whose undisturbed Mach numbers were 3.12 and 3.81. It was found that the position of transition to turbulence moved downstream as the tip radius was increased when its distance from the tip was greater than about 100 times the tip radius. When the position of transitions was nearer the tip than this, it moved upstream as the tip radius increased. Pitot traverses of the boundary layer were made, and it was found that transition occurred (in a given stream) at a constant value of the Reynolds number, R Delta 2, which is based on conditions at the edge of the boundary layer, and on its momentum thickness. It is demonstrated that, although the Reynolds number per inch near the tip of a blunt cone is smaller than that on a sharp cone, the momentum thickness on a blunt cone is greater than would be expected on a sharp cone. Some preliminary theoretical results are quoted which predict qualitatively all the above results. The assumptions made in this theory remain, however, unjustified. (Author)

Descriptors :   *BLUNT BODIES, *BOUNDARY LAYER, *CONICAL BODIES, *SHEAR STRESSES, *SUPERSONIC FLOW, *TURBULENT BOUNDARY LAYER, MACH NUMBER, REYNOLDS NUMBER, ROLLER BEARINGS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE