A New Technique for establishment of Aero-Elastic Model

Abstract

The subject interest of nonlinear unsteady aerodynamics is one of great interest in the aerospace community. The interest is due to the fact that nonlinear unsteady aerodynamic behavior can have a significant effect on the performance and stability of a flight vehicle. To deal with such the aero elastic problem one generally models it by establishing state space equations. In this study, a new technique for determination of transonic nonlinear lift was developed based on discrete reduced-order Volterra series instead of relying on classical approach "eigen system realization algorithm (ERA)". In this model, one can find out that several time-delayed terms appear. Here we employ Taylor formula to expand these time-delayed terms at the current instant, and then they are vanished. In this study, we also explain how to identify discrete reducedorder kernels. As an example, the two sets of curves between the convolution kernel function method and CFD results match fine.