Aerodynamic and Aeroelastic Analysis of Flying Wing with Split Drag-Rudder

Abstract

In this paper, aerodynamic and aeroelastic characteristics of flying wing with split drag-rudder are studied, using aeroelastic analysis method in time domain based on CFD/CSD (Computational Fluid Dynamics, CFD; Computational Structural Dynamics, CSD) coupling. Unsteady aerodynamic is obtained by solving Euler equations, and structural response is calculated by solving structural dynamic equations. CFD/CSD coupling uses predictive-multiple step loose coupling method, coupling interface data exchange uses constant volume transformation (CVT) method, and dynamic grid deforming uses transfinite interpolate (TFI) method. The flutter boundary of AGARD 445.6 wing is calculated with the coupled CFD/CSD method. Comparison between present results and experimental data is given, and there are good agreements in subsonic and transonic region, respectively, which illustrate the reliability of this method. Then, for the flying wing, the aerodynamic and aeroelastic characteristics are studied and revealed. Lift and drag coefficients with various cracking angles and angles of attack are calculated, and some change laws are concluded. Finally, flutter boundary of the flying wing is computed, and lift and drag coefficients in rigid and elastic conditions are given, after which several laws are summarized.