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A nonlinear unsteady one-dimensional theory for wings in extreme ground effect

Published online by Cambridge University Press:  19 April 2006

E. O. Tuck
Affiliation:
Applied Mathematics Department, University of Adelaide

Abstract

Flow induced by a body moving near a plane wall is analysed on the assumption that the normal distance from the wall of every point of the body is small compared to the body length. The flow is irrotational except for the vortex sheet representing the wake. The gap-flow problem in the case of unsteady motion is reduced to a nonlinear first-order ordinary differential equation in the time variable. In the special case of steady flow, some known results are recovered and generalized. As an illustration of the unsteady theory, the problem is solved of a flat plate falling toward the ground under its own weight, while moving forward at uniform speed.

Type
Research Article
Copyright
© 1980 Cambridge University Press

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References

Bagley, J. A. 1961 The pressure distribution on two-dimensional wings near the ground. Aero. Res. Counc. R. & M. no. 3238.Google Scholar
Barrows, T. M. 1971 Progress on the ram-wing concept, with emphasis on lateral dynamics. U.S. Dept. Transp. Rep. DOT-TSC-FRA-71-7.Google Scholar
Barrows, T. M. & Widnall, S. 1970 The aerodynamics of ram-wing vehicles for application to high-speed ground transportation. A.I.A.A. Paper, no. 70–142. 8th Aerospace Sci. Meeting, New York.Google Scholar
Gallington, R. W. & Miller, M. K. 1970 The ram-wing: a comparison of simple one dimensional theory with wind tunnel and free flight results. A.I.A.A. Paper, no. 70–971. Guidance, Control and Flight Mech. Conf., Santa Barbara, California.Google Scholar
Norrbin, N. H. 1974 Bank effects on a ship moving through a short dredged channel. 10th Symp. Naval Hydro., Cambridge, Mass. Proc., Office of Naval Res., Washington, D.C., pp. 7188.
Pistolesi, E. 1937 Ground effect-theory and practice. N.A.C.A., T.M. no. 828.Google Scholar
Strand, T., Royce, W. W. & Fujita, T. 1962 Cruise performance of channel-flow ground-effect machines. J. Aero. Sci. 29, 702711.Google Scholar
Taylor, G. I. 1967 Low-Reynolds-Number Flows. 16 mm color sound film, Encyclopaedia Britannica Educational Corp., Chicago, Illinois.
Tuck, E. O. 1975 Matching problems involving flow through small holes. Adv. Appl. Mech. 15, 89158.Google Scholar
Tuck, E. O. 1978a Hydrodynamic problems of ships in restricted waters. In Annual Review of Fluid Mechanics (ed. Van Dyke, M.) 10, 3344. Annual Reviews Inc.
Tuck, E. O. 1978b Unsteady Small-Gap Ground Effects, Engineering Science Report 78–1, Calif. Inst. of Tech., Pasadena.Google Scholar
Tuck, E. O. 1979 Applied Mathematics Report T7906, University of Adelaide.
Tuck, E. O. & Newman, J. N. 1974 Hydrodynamic interactions between ships. 10th Symp. Naval Hydro., Cambridge, Mass. Proc., Office of Naval Res., Washington, D.C., pp. 3570.Google Scholar
Widnall, S. E. & Barrows, T. M. 1970 An analytic solution for two- and three-dimensional wings in ground effect. J. Fluid Mech. 41, 769792.Google Scholar
Yih, C. S. 1974 Fluid mechanics of colliding plates. Phys. Fluids 17, 19361940.Google Scholar