Accession Number : ADA191777

Title :   Comparison of the Wall Pressure Fluctuations in Artificially Generated Turbulent Spots, Natural Transition and Turbulent Boundary Layers.

Descriptive Note : Professional paper,

Corporate Author : NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA

Personal Author(s) : Mautner, Thomas S

PDF Url : ADA191777

Report Date : Jan 1988

Pagination or Media Count : 9

Abstract : Experiments have been conducted to measure the wall pressure fluctuations associated with artificially generated turbulent spots in a laminar boundary layer. The results show that both the rms wall pressure and the wall pressure spectra of turbulent spots are influenced by the local mean flow pressure gradient. The zero and favorable pressure gradient wall pressure data are in agreement with turbulent boundary layer results. However, the current spot data shows that, in the presence of an adverse pressure gradient, the spot's rms wall pressure is approximately 1.5-2.5 times larger than that found for the zero and favorable pressure gradient cases. These results are in general agreement with the adverse pressure gradient data of Huang and Hannan (1975). Additionally, the nearly constant magnitude of the spot's adverse pressure gradient wall pressure spectrum indicates a nearly even distributions of energy with frequency. Keywords: Turbulent boundary layer, Laminar boundary layer, Wall pressure fluctuations.

Descriptors :   *LAMINAR BOUNDARY LAYER, *PRESSURE GRADIENTS, ADVERSE CONDITIONS, PRESSURE, SPECTRA, TRANSITIONS, TURBULENT BOUNDARY LAYER, VARIATIONS, WALLS

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE