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Unsteady aerodynamic loads on an aerofoilwith a deflecting tab

Published online by Cambridge University Press:  04 July 2016

J. P. Narkiewicz ,
A. Ling  and
G. T. S. Done
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Abstract

A thin, low cambered aerofoil with a tab at thetrailing edge in inviscid, incompressible,two-dimensional, unstalled flow with varyingfreestream velocity and arbitrary, different motionsfor both aerofoil and tab is considered. The generalexpressions for unsteady lift and aerodynamic momenton aerofoil and tab are derived within theassumptions of potential theory.

To verify the approach proposed in this paper, theclassical Theodorsen case of an oscillating aerofoilis adopted. For this case, aerofoil loads arecalculated in the time domain by applying an inverseLaplace transformation to the approximation of thelift deficiency function in the frequencydomain.

The comparison of the results calculated by this methodwith those obtained by other methods and experimentsshows good agreement, which validates the generalformulation. The loads on an aerofoil havingdifferent frequencies for main aerofoil pitch andtab deflection are calculated.

Information

Type
Research Article
Information
The Aeronautical Journal , Volume 99 , Issue 987 , September 1995 , pp. 282 - 292
Copyright
Copyright © Royal Aeronautical Society 1995 

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Footnotes

1.

Warsaw University of Technology, Warsaw,Poland.

2.

Chinese Helicopter Research and DevelopmentInstitute, Jingdezhen, Peoples' Republic ofChina.

3.

City University, London, UK

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