Accession Number : AD0600476

Title :   SURFACE AND VOLUME SOUND FROM BOUNDARY LAYERS,

Corporate Author : MINNESOTA UNIV MINNEAPOLIS INST OF TECH

Personal Author(s) : Meecham,William C.

Report Date : 1963

Pagination or Media Count : 25

Abstract : It is shown for turbulent boundary layers that surface, dipole sound is in general very much less than volume, quadrupole sound. This is so for two reasons: first, the relative volume sound is increased by several orders of magnitude because of shear-flow enhancement within the boundary layer. Secondly, the dipole sound intensity is shown, through the use of image argument similar to that used in the discussion of flat boundary layers, to be reduced by a factor of (L/R) squared where L is the boundary layer thickness and R is the surface radius of curvature. A discussion of irregular surface bumps shows that such imperfections may be the source of significantly large dipole sound. (Author)

Descriptors :   (*TURBULENT BOUNDARY LAYER, SOUND), FLUID DYNAMICS, BOUNDARY LAYER, SURFACE PROPERTIES

Distribution Statement : APPROVED FOR PUBLIC RELEASE