Accession Number : ADA139499

Title :   The Effect of Discrete Spanwise Regions of Bleed on Pseudo-Two Dimensional Base Flow at Transonic Speeds,


Personal Author(s) : Pollock,N

PDF Url : ADA139499

Report Date : Jul 1983

Pagination or Media Count : 62

Abstract : A preliminary experimental study of a new type of pseudo-two-dimensional bluff base consisting of a series of rectangular prismatic protrusions spaced along the span with base bleed into the regions between the protrusions is presented. A base geometry was derived which had less drag at subsonic and transonic speeds than the best reported non-bleed arrangement for bleed mass flow coefficients (based on the mass flux swept by the model frontal area) in the range 0.02 to 0.04. A simple two-dimensional bleed arrangement requires a bleed coefficient greater than 0.08 to achieve the same subsonic base drag.

Descriptors :   *Base flow, *Transonic airfoils, *Bleed systems, Aerodynamic drag, Wake, Drag reduction, Mass flow, Coefficients, Base pressure, Two dimensional flow, Subsonic characteristics, Aerodynamic configurations, Trailing edges, Blunt bodies, Low drag airfoils, Protuberances, Wind tunnel models, Tables(Data), Australia

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE