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Asymptotic Expansion for Transient Forces from Quasi-Steady Subsonic Wing Theory

Published online by Cambridge University Press:  07 June 2016

H. C. Garner  and
R. D. Milne
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Summary

A simple general expression is obtained for the rate of change of generalised aerodynamic damping coefficients with respect to frequency parameter in the limit as frequency tends to zero. The expression is directly proportional to aspect ratio and does not depend explicitly on Mach number. The result is consistent with calculated pitching derivatives from finite-frequency theory.

This extension of quasi-steady theory is applied to determine the leading transient term of the asymptotic expansion for large time of generalised forces due to an indicial upwash field. The expansion has direct relevance to the use of quasi-steady aerodynamic derivatives in the field of stability and control.

Type
Research Article
Information
Aeronautical Quarterly , Volume 17 , Issue 4 , November 1966 , pp. 343 - 350
Copyright
Copyright © Royal Aeronautical Society. 1966

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References

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