A SUGGESTED NUMERICAL ALGORITHM FOR GEOMETRICALLY NONLINEAR AEROELASTIC BEHAVIOR

Document Type : Original Article

Author

PhD., Assist. Prof., Karary Academy of Technology – Khartoum – Sudan.

Abstract

A numerical simulation algorithm has been developed to investigate the effects of geometric nonlinearities on dynamic aeroelastic behavior of wing-like cantilever structures. A geometrically nonlinear finite element formulation relevant to flexible structures has been adopted to model the structure using a degenerate-continuum shell element along with total Lagrangian formulation. Subsonic doublet lattice method (DLM) has been used to model the unsteady aerodynamics. To ensure full coupling between the structural and aerodynamic networks, infinite plate spline technique has been employed. This has facilitated the transfer of loads and displacements during the nonlinear analysis where the aerodynamic load is applied incrementally through a unique two-level time stepping procedure developed in the present work. The results obtained highlighted the effectiveness of the suggested numerical algorithm in capturing geometrically nonlinear behavior. Geometric nonlinearities showed additional nonlinear features that are not predicted by the linear approach.

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