Accession Number : AD0428700

Title :   MEASUREMENTS OF THE FLUCTUATING STATIC AND TOTAL-HEAD PRESSURES IN A TURBULENT WAKE,

Corporate Author : DAVID TAYLOR MODEL BASIN WASHINGTON D C

Personal Author(s) : Strasberg,M.

Report Date : DEC 1963

Pagination or Media Count : 27

Abstract : The use of probe tubes for measuring the fluctuating static and stagnation-point pressures in subsonic turbulent wakes is discussed and estimates are made of the magnitude of several sources of error. It is shown that the mere presence of a probe tube in a turbulent flow causes the measured mean-square value of the fluctuating static pressure to exceed the true value by about (1/4) (rho v sub t squared) squared, where v sub t is the fluctuating velocity component normal to the tube. Although this error is just about equal to the magnitude of the fluctuations expected in isotropic turbulence, the fluctuations in shear flows can exceed the error by enough to be measurable. The results of measurements of fluctuating pressure made in the wake behind a cylinder are presented. Data are given on the rms values and the spectra of the fluctuating static and total-head pressures, and on the cross correlations of these pressures with the fluctuating velocity. (Author)

Descriptors :   (*WAKE, INSTRUMENTATION), (*TURBULENCE, PRESSURE GAGES), STAGNATION POINT, SUBSONIC FLOW, PRESSURE, MEASUREMENT, CYLINDRICAL BODIES, VELOCITY, ERRORS, WIND TUNNELS, AERODYNAMIC CHARACTERISTICS, NOISE

Distribution Statement : APPROVED FOR PUBLIC RELEASE