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Pitch Ramp Maneuvers as a Prototypical Case in Low Reynolds Number Unsteady Aerodynamics

OL Michael, Kenneth Granlund, Luis Bernal

Abstract


We revisit the classical problem of a flat plate in linear pitch ramp, with and without streamwise deceleration, motivated by the application of perching Micro Air Vehicles. Lift and drag coefficients can reach values 2-4 higher than quasi-steady maxima, depending on pitch rate. Streamwise deceleration causes increase in peak force coefficients, but has little effect at low and moderate angle of attack. Peak lift coefficient is seen to correlate with the
saturation of the leading edge vortex and its subsequent shedding. Comparison between 2D and aspect ratio 2.0 plates comports with quasi-steady theory.

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DOI: http://dx.doi.org/10.21535%2FProICIUS.2010.v6.483

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