A Navier-stokes based study into linearity in transonic flow for flutter analysis

Resumo

A finite-difference Navier-Stokes code is used in order to study the linearity of aerodynamic loads with respect to the dynamic angle of attack in threedimensional transonic flow. Steady and unsteady pressure coefficients for prescribed rigid angle of attack motion are computed for a F-5 wing for which the method has been previously validated. The study is aimed at identifying the conditions under which approximate flutter analyses based on corrections to aerodynamic influence coefficients may be used. Results indicate that higher harmonics of the unsteady loads are present in the aerodynamic response and that the boundaries for linear behavior depend on the spanwise location along the wing. © 2002 by the author(s). Published by the American Institute of Aeronautics and Astronautics, Inc.