CFD-CSD Coupled Aeroelastic Analysis Of Flexible Flapping Wings For MAV Applications

摘要

A coupled CFD-CSD solver is used to simulate the aerodynamics of flexible flapping wings for MAV applications. The CFD solver is a compressible RANS solver developed at University of Maryland, called OVERTURNS. The open source general-purpose multibody dynamics solver MBDyn is used as the structural solver after an extension to take into account geometrically nonlinear shells, making it possible to analyze plates/membranes with large deformations. Validation of the two codes for flapping wings/plates is carried, out independently. The solvers are then coupled and validated against prior experiments and predictions of a simplified configuration involving a spanwise flexible wing in pure plunge. In-house experiments are also carried out on MAV wings in an open jet wind tunnel. Rigid wings are tested for pure flap and flap plus pitch kinematics. Flexible wings with root flap actuation are also tested in the wind tunnel and experiments are carried out to structurally characterize them. CFD and CFD-CSD analyses are carried out on the rigid and flexible wings, respectively. Good correlation is observed between the experimental and analytical results. Further, the analysis is used to study the flow physics in greater detail. A high fidelity, well validated CFD-CSD solver is developed which may help in designing the next generation flapping wing MAVs.