Transonic aerodynamics of flexible wings

This paper presents a method capable of predicting the bending and twisting of the real wings by coupling a transonic CFD code with a thin-walled structure analysis program (TWSAP). The linear structural capabilities available in the NASTRAN structural analysis software were utilized to predict the bending and twisting of a simplified stick model of the actual wing. The thin-walled structure analysis results were validated for open and closed sections along with multi-cellular sections. The deformations predicted using the simplified finite element model (stick model) of the Bombardier experimental transonic high aspect ratio wing (W20) were I in very good agreement. with the full FEM of the wing. Preliminary results show that the use of simplified FEM of the aircraft wings provide a quick and economic option for predicting the-aerodynamic performance of flexible wings in flight. Results obtained for the undeformed and the static equilibrium (convergence) states of the W20 wing are presented, the latter, being in very good agreement with experimental measurements.