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Autorotation of an elliptic cylinder about an axis perpendicular to the flow

Published online by Cambridge University Press:  19 April 2006

Hans J. Lugt
Hans J. Lugt
Affiliation:
David W. Taylor Naval Ship Research and Development Center, Bethesda, Maryland 20084, U.S.A.
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Abstract

Autorotation of an elliptic cylinder about an axis fixed perpendicular to a parallel flow is explained in this paper by means of numerical solutions of the Navier-Stokes equations. Potential-flow theory predicts, for constant angular velocity, half a period in which a torque supports rotation and half a period in which it opposes rotation, with vanishing torque in the average. This balance is disturbed by viscous-flow effects in such a way that, for a given angular velocity, vortex shedding either damps rotation or, under certain conditions, favours rotation. The proper interplay of those conditions, which include synchronization of vortex shedding and rate of rotation, results in auto-rotation. The numerical results for Re [les ] 400 are compared with experimental data for Re = 90000 from the literature. The agreement of the force coefficients and the large-scale flow patterns is surprisingly good.

Information

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 99 , Issue 4 , 29 August 1980 , pp. 817 - 840
Copyright
© 1980 Cambridge University Press

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References

Bairstow, L. 1939 Applied Aerodynamics, 2nd edn, cha. V, p. 212. London: Longman.
Griffin, O. M. & Ramberg, S. E. 1974 The vortex-street wakes of vibrating cylinders. J. Fluid Mech. 66, 553.Google Scholar
Iversen, J. D. 1979 Autorotating flat-plate wings: the effect of the moment of inertia, geometry and Reynolds number. J. Fluid Mech. 92, 327.Google Scholar
Kry, P. R. & List, R. 1974 Angular motions of freely falling spheroidal hailstone models. Phys. Fluids 17, 1093.Google Scholar
Lamb, H. 1945 Hydrodynamics, 6th edn. Dover.
Lugt, H. J. 1978 Autorotation of plates. David W. Taylor Naval Ship R & D Center Rep. no. 78/058.Google Scholar
Lugt, H. J. & Haussling, H. J. 1974 Laminar flow past an abruptly accelerated elliptic cylinder at 45° incidence. J. Fluid Mech. 65, 711.Google Scholar
Lugt, H. J. & Haussling, H. J. 1978 The acceleration of thin cylindrical bodies in a viscous fluid. J. Appl. Mech. 45, 1.Google Scholar
Lugt, H. J. & Ohring, S. 1977 Rotating elliptic cylinders in a viscous fluid at rest or in a parallel stream. J. Fluid Mech. 79, 127.Google Scholar
Maxwell, J. C. 1890 On a particular case of the descent of a heavy body in a resisting medium. Scientific Papers, p. 115. Cambridge University Press.
Riabouchinsky, D. P. 1935 Thirty years of theoretical and experimental research in fluid mechanics. J. Roy. Aero. Soc. 39, 282.Google Scholar
Smith, A. M. O. 1953 On the motion of a tumbling body. J. Aero. Sci. 20, 73.Google Scholar
Smith, E. H. 1971 Autorotating wings: an experimental investigation. J. Fluid Mech. 50, 513.Google Scholar
Taneda, S. 1977 Visual study of unsteady separated flows around bodies. Prog. Aero. Sci. 17, 287.Google Scholar
Thoman, D. C. & Szewczyk, A. A. 1966 Numerical solutions of time dependent two dimensional flow of a viscous, incompressible fluid over stationary and rotating cylinders. Univ. Notre Dame, Dept. Mech. Engng Tech. Rep. no. 66-14.Google Scholar