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The advantages of swept, sharp edges that generate controlled (or fixed) three-dimensional flow separations on a vehicle, because of the qualitatively unchanging flowfield developed throughout the range of flight conditions are promoted in perference to allowing uncontrolled (or unfixed) separations. The three-dimensional viscous flowfields and vortical interactions about typical components such as delta wings and bodies at incidence are discussed, in apposition to their use on selected examples of current flight vehicles., Summary in French.

Experimentally determined wall pressure distributions, local surface shear stresses and their directions, and detailed turbulent boundary-layer traverses in near zero heat transfer conditions, are presented through skewed shock/boundary-layer interaction regions generated by a wedge standing normal to a test wall. The mainstream Mach numbers were 2 and 4, while the Reynolds number based on the undisturbed test boundary-layer thickness of 0.2-in., growing along the nozzle sidewall of the NAE 5 X 5-in. blowdown wind tunnel, was 200,000. Tangential air injection at a jet exit Mach number of 3 was then introduced into the 3D shock separated Mach 2 boundary layer, to control the separation. The optimum direction of blowing was found to be along a line somewhere between the deflected surface of the wedge and the line of the oblique shock wave., Also pub. as ISSN-0077-5541.

Current knowledge and understanding of the fluid physics of 2D and 3D flow separation and reattachment, particularly for turbulent flows, is limited. It is necessary that high quality, carefully planned 2D and 3D boundary layer experiments be conducted to obrain dependable experimental data to enhance our basic knowledge, and for use in verification, validation and development of theoretical prediction methods. These complete, unambiguous data sets should include detailed documentation of all measurable quantities, both mean and fluctuating, at the wall, in the viscous boundary layer and in the external flowfield. Emphasis should be placed on redundant measurement techniques to ensure high data reliability. (Author), See also Conference Proceedings, Rept. no. AGARD-CP-168, AD-A020 001, and Rept. no. AGARD-CP-168-Suppl, AD-A025 662. NATO Furnished.

Flow-field measurements have been made to determine the effects of core blowing on vortex breakdown and control. The results of these proof-of-concept experiments clearly demonstrate the usefulness of water tunnels as test platforms for advanced flow-field simulation and measurement., This article is from 'Aerodynamic and Related Hydrodynamic Studies Using Water Facilities, Symposium of the Fluid Dynamics Panel' Held in Monterey, California on 20-23 October 1986, AD-A199 357, p2-1-3-15.

This review provides an illustrated introduction laying the knowledge base for vortical flows about three-dimensional configurations that are of typical interest to aerodynamicists and researchers in fluid mechanics. The paper then compiles a list of ten issues, again in illustrative format, that the authors deem important to the understanding of complex vortical flows. These issues and our responses to them provide, it is hoped, a skeletal framework on which to hang the ensuing conference proceedings. (Author), This article is from 'Aerodynamics of Vortical Type Flows in Three Dimensions: Conference Proceedings Held at Rotterdam, Netherlands on 25-28 April 1983,' AD-A135 157, p1-1-1-31.

The effects of unequal porosity factors, ascribed to the floor and ceiling of two-dimensional wind tunnel test sections, are investigated with a simplified mathematical model that utilizes a point vortex and a point doublet placed mid-way between the two walls. Closed form solutions are derived, using the method of images for wall pressure distributions, and corrections to Mach number and model angle of attack.