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Method for aerodynamic unsteady forces timecalculations on an F/A-18 aircraft

Published online by Cambridge University Press:  03 February 2016

D. E. Biskri  and
R. M. Botez
D. E. Biskri
Affiliation:
École de technologie supérieure, Department of Automated Production Engineering, Montréal, Québec, Canada
R. M. Botez
Affiliation:
École de technologie supérieure, Department of Automated Production Engineering, Montréal, Québec, Canada
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Abstract

In this paper, a new original method based on the leastsquares method is presented for the conversion ofunsteady aerodynamic forces from frequency intoLaplace domain, in which the error is written in ananalytical form as a function of the Laplacevariable, similar to the analytical form of theaerodynamic forces calculated by use of the leastsquares method. This method is applied on an F/A-18aircraft (14 symmetric and 14 anti-symmetric modes)for one Mach number and for a set of 14 reducedfrequencies. Two different types of results areobtained and analysed: aerodynamic forceapproximations in the Laplace domain and flutterspeeds and frequencies values. For a bettercomparison of these results, different lag termnumbers are used. Results obtained by this newmethod are better in terms of execution speed andprecision than the results obtained by use of theleast squares method.

Information

Type
Research Article
Information
The Aeronautical Journal , Volume 112 , Issue 1127 , January 2008 , pp. 27 - 32
Copyright
Copyright © Royal Aeronautical Society 2008 

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