Sensitivity Analysis for Coupled Aero-structural Systems

M MDO OML A novel method has been developed for calculating q gradients of aerodynamic force and moment coefi% TSV cients for an aeroelastic aircraft model. This method t/c uses the Global Sensitivity Equations (GSE) to acX count for the aero-structural coupling, and a reduceda order modal analysis approach to condense the cou6 piing bandwidth between the aerodynamic and strucA rural models. Parallel computing is applied to reduce A the computational expense of the numerous high fiA delity aerodynamic analyses needed for the coupled ALE aero-structural system. Good agreement is obtained 4) between aerodynamic force and moment gradients computed with the GSE/modal analysis approach and the same quantities computed using brute-force, computationally expensive, finite difference approximations. A comparison between the computational expense of the GSE/modal analysis method and a pure finite difference approach is presented. These results show that the GSE/modal analysis approach is the more computationally efficient technique if sensitivity analysis is to be performed for two or more aircraft design parameters.