Accession Number : AD0436675

Title :   MEASUREMENTS OF THE CORRELATION BETWEEN THE FLUCTUATING VELOCITIES AND THE FLUCTUATING WALL PRESSURE IN A THICK TURBULENT BOUNDARY LAYER,

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

Personal Author(s) : Willmarth, W. W. ; Wooldridge, C. E.

Report Date : APR 1963

Pagination or Media Count : 62

Abstract : Turbulent motion in a thick (5-inch) boundary layer with zero longitudinal pressure gradient which is produced by natural transition on a smooth surface was studied. Measurements were made of the space-time correlation between the fluctuating wall pressure and the fluctuating velocities in the layer, and between the fluctuating wall pressure and the time derivative of the fluctuating velocity normal to the wall. At any height in the boundary layer, the velocity disturbance which was correlated with the wall pressure disturbances was convected at the local mean speed. The correlation of the wall pressure with the longitudinal velocity was opposite in sign to the correlation of the wall pressure with the velocity normal to the wall. This implied that the part of the velocity field which is correlated with the wall pressure also produces turbulent shear. (Author)

Descriptors :   (*TURBULENT BOUNDARY LAYER, MEASUREMENT), (*AIRCRAFT NOISE, TURBULENT BOUNDARY LAYER), VELOCITY, PRESSURE, SHEAR STRESSES, VORTICES, SUBSONIC CHARACTERISTICS, CORRELATION TECHNIQUES, EXPERIMENTAL DATA, THEORY, INSTRUMENTATION, MOTION, OSCILLATION.

Distribution Statement : APPROVED FOR PUBLIC RELEASE