Accession Number : AD0770581

Title :   Flow Through a Sudden Enlargement Subjected to Large Amplitude Low Frequency Axial Oscillations.

Descriptive Note : Technical rept.,

Corporate Author : LEHIGH UNIV BETHLEHEM PA DEPT OF MECHANICAL ENGINEERING AND MECHANICS

Personal Author(s) : Rockwell,D. ; Siddiqui,N. ; Rehmani,S.

Report Date : AUG 1973

Pagination or Media Count : 59

Abstract : An experimental investigation was undertaken for the case of flow through a sudden expansion subjected to large amplitude low frequency axial oscillations which formed a standing wave in the receiver duct. Measurements included integrated velocity fluctuation amplitudes and velocity and wall pressure fluctuation amplitudes at the wavemaker frequency. Reattachment of the flow drastically attenuates the fluctuation parameters. Oscilloscope traces show a tendency toward flow relaminarisation during the accelerating phase of the cycle, and a turbulent bursting to high turbulence intensity when the time dependent pressure gradient changes from negative to positive. (Author)

Descriptors :   *Flow fields, *Turbulent flow, Turbulence, Turbulent boundary layer, Waveforms, Flow visualization, Fluerics

Subject Categories : Fluidics and Fluerics

Distribution Statement : APPROVED FOR PUBLIC RELEASE