MODAL-BASED STRUCTURAL OPTIMIZATION WITH STATIC AEROELASTIC AND STRESS CONSTRAINTS

The modal-based aeroelastic optimization approach is reformulated and extended such that it can deal with more structural analysis and optim ization features. The disciplines treated in this paper are statics un der fixed loads and static aeroelasticity of free-free aircraft, The n ew formulation includes the application of stress constraints under fi red and varied external loads, and the effects of inertial changes on aeroelastic trim, It also facilitates the integration of the modal-bas ed option in common finite element structural optimization schemes. Th e new scheme is applied to realistic design cases using the multidisci plinary automated structural optimization system ASTROS code. Applicat ion cases of 3761 and 26,259 degrees of freedom exhibit CPU time reduc tion factors of 4-122 in comparison with the conventional discrete app roach.