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Method for aerodynamic unsteady forces time calculations 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 least squares method is presented for the conversion of unsteady aerodynamic forces from frequency into Laplace domain, in which the error is written in an analytical form as a function of the Laplace variable, similar to the analytical form of the aerodynamic forces calculated by use of the least squares method. This method is applied on an F/A-18 aircraft (14 symmetric and 14 anti-symmetric modes) for one Mach number and for a set of 14 reduced frequencies. Two different types of results are obtained and analysed: aerodynamic force approximations in the Laplace domain and flutter speeds and frequencies values. For a better comparison of these results, different lag term numbers are used. Results obtained by this new method are better in terms of execution speed and precision than the results obtained by use of the least squares method.

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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