Accession Number : ADD018171

Title :   Enhancement of Flow Mixing by a Frequency Tunable Cavity.

Descriptive Note : Patent, Filed 30 Jun 94, patented 28 May 96,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Yu, Kenneth H ; Schadow, Klaus C ; Smith, Robert A

Report Date : 28 May 1996

Pagination or Media Count : 11

Abstract : A shear layer of a fluid flow has relatively large vortical structures generated by acoustic forcing from oscillations induced in a cavity closely adjacent to the flow so that these structures enhance mixing at the layer. The forcing frequency is selected by varying the dimensions of the cavity, and several cavities of different dimensions may be provided for forcing at different frequencies, including beat frequencies. The cavity provides passive, high amplitude forcing effective with a compressible shear layer due to high speed flow, including supersonic flow. Cavities of differing configuration provide forcing for fluid flow from nozzles of different geometries. The most effective enhancement is provided by particular excitation frequencies generated by a cavity having a size selected in accordance with dimension-less relations between the flow parameters and nozzle geometry.

Descriptors :   *COMPRESSIBLE FLOW, *SHEAR FLOW, *PATENTS, *CAVITATION, OPTIMIZATION, VORTICES, SUPERSONIC FLOW, OSCILLATION, BOUNDARY LAYER FLOW, JET MIXING FLOW, ACOUSTIC RESONANCE

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE