Modal-Based Structural Optimization with Static Aeroelastic and Stress Constraints

Abstract

The modal-based aeroelastic optimization approach is reformulated and extended such that it can deal with more structural analysis and optimization features. The disciplines treated in this paper are statics under e xed loads and static aeroelasticity of free ‐ free aircraft. The new formulation includes the application of stress constraints under e xed and varied external loads, and the effects of inertial changes on aeroelastic trim. It also facilitates the integration of the modal-based option in common e nite element structural optimization schemes. The new scheme is applied to realistic design cases using the multidisciplinary automated structural optimization system ASTROS code. Application cases of 3761 and 26,259 degrees of freedom exhibit CPU time reduction factors of 4 ‐ 122 in comparison with the conventional discrete approach.