Method and apparatus for reducing turbulent skin friction

Aeronautics and astronautics – Aircraft sustentation – Sustaining airfoils

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244208, 244209, 244200, 244130, B64C 2102, B64C 2110

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active

049326120

ABSTRACT:
A method and apparatus for reducing the skin friction on objects in relative motion to a field of fluid. The areas of relative low speed motion are fixed to align with a series of ridges on the surface of the object. The areas of low speed motion aligned with the ridges are removed by suction from the turbulent boundary layer which results in a reduction of drag on the object. An alternative embodiment injects fluid into areas of relative high speed between the ridges to reduce the shear and the drag caused by it. Selective suction and injection are combined in one apparatus in a second alternative embodiment. A fourth embodiment injects a polymeric solution to reduce drag. A fifth embodiment heats the fluid in specified areas to reduce drag. A sixth embodiment uses a compliant material in specified areas of the surface in contact with flowing fluid to reduce drag.

REFERENCES:
patent: 2608171 (1952-08-01), Pearce
patent: 2873931 (1959-02-01), Fleischmann
patent: 3161385 (1964-12-01), Kramer
patent: 3289623 (1966-12-01), Gray et al.
patent: 3588005 (1971-06-01), Rethorst
patent: 3604661 (1971-09-01), Mayer
patent: 3628488 (1971-12-01), Gibson
patent: 4516747 (1985-05-01), Lurz
Walsh, "Turbulent Boundary Layer Drag Reduction Using Riblets", AIAA Paper #82-0169, Jan. 11-14, 1982.
Gad-el-Hak & Blackwelder, A Drag Reduction Method for Turbulent Boundary Layers, 1987, AIAA-87-0358, pp. 1-12 (not prior art).
Liepmann & Nosenchuck, Active Control of Laminar-Turbulent Transition, 1982, J. Fluid Mech., vol. 118, pp. 187-204.
Bacher & Smith, A Combined Visualization-Anemometry Study of the Turbulent Drag Reducing Mechanisms of Triangular Micro-Groove Surface Modifications, 1985, AIAA-85-0548, pp. 1-10 (not prior art).
Arakeri & Narashima, Effect of Pulsed Slot Suction on a Turbulent Boundary Layer, 1983, AIAA Journal, vol. 21, pp. 306-307.
Sokolov et al., A "Turbulent Spot" in an Axisymmetric Free Shear Layer. Part 1, 1980, J. Fluid Mech., vol. 98, Part 1, pp. 65-95.
Verollet et al., Turbulent Boundary Layer with Suction and Heating to the Wall, 1972, Heat & Mass Transfer in Boundary Layers, vol. 1, pp. 157-160.
Gad-el-Hak & Blackwelder, The Discrete Vortices from a Delta Wing, 1985, AIAA Journal, vol. 23, No. 6, pp. 961-962.
Riley & Gad-el-Hak, The Dynamics of Turbulent Spots, Frontiers in Fluid Dynamics, pp. 123-155, 1985 (not prior art).
Gad-el-Hak et al., On the Interaction of Compliant Coatings with Boundary-Layer Flows, 1984, J. Fluid Mech., vol. 140, pp. 257-280.

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