Analysis and Computational Study of the Aerodynamics, Aeroelasticity and Flight Dynamics of Flapping Wing Ornithopter Using Linear Approximation

摘要

The present work addresses the aerodynamics, aeroelasticity and flight dynamics of birdlike bio-inspired bi-wing flapping wing ornithopter in forward flight The main interest is to compare the dynamics of rigid and flexible flapping wing in forward flight First, a generic approach is followed to model the geometry, kinematics and aerodynamics of flapping wing ornithopter by considering a three-dimensional rigid and thin wing in flapping and pitching motion with and without phase lag. The unsteady aerodynamic approach incorporates viscous effects and leading-edge suction. Next a fundamental representation of unsteady air loads and structural flexibility interaction is developed for the analysis and numerical simulation based on a generic linear aeroelastic analysis using forward speed and oscillatory flapping motion as disturbances, to find out the influence of wing flexibility on its aeroelastic stability and aerodynamic performance. Further, a simplified and generic model flight dynamic model is presented based on using the same aerodynamic approach, by only considering the equation of motion in the plane of symmetry to gain insight for further development of refined model. Parametric studies are carried out both for the aeroelastic and flight dynamic problems to assess the plausibility of the present approach.