Aerodynamic forces based on an error analytical formulation for aeroservoelasticity studies on an F/A-18 aircraft

Abstract

Two classical methods are used in the literature to approximate the unsteady generalized forces from the frequency domain Q(k) to the Laplace domain Q(s) and these methods are the least squares and the minimum state (MS). In this article, a new method is presented, called the corrected minimum state (CMS), on the basis of the standard MS approximation method. This new CMS method uses an analytical form of the error as a function of Laplace variable similar to the analytical form of the aerodynamic forces calculated with the MS method. This new method is applied to an F/A-18 aircraft and it is found that the CMS method brings improvements in the approximation results in comparison with the standard MS method. It is shown that the use of the CMS method on an F/A-18 aircraft will give better results in terms of convergence speeds and precision than the MS method.