Abstract:
Wing morphing technology is anticipated as the undeniable future of modern flight vehicle design. Morphing aircrafts are the flight vehicles that can reconfigure their shape during flight in order to achieve multi-mission flight performance with enhanced flying range and endurance capabilities. However, this promising technology poses cross-disciplinary challenges that encourage widespread design possibilities. Current idea of integrating the wing morphing with Unmanned Air Vehicles (UAVs) has been fueled by the miniaturization of technology. This research aims to investigate the flight dynamic characteristics of various symmetrically morphed wings configurations that can be incorporated in small scale UAVs. The objective of this study is to analyze the effects of geometric variations in wing planform by varying wing span, sweep and dihedral angle on the aircraft stability, all through computational approach. Linearized rigid body six Degree of Freedom (6-DoF) equations of motion provide the governing framework for stability analysis. Computational aerodynamic and stability analysis were performed using an open source code XFLR5 based on Vortex Lattice Method (VLM) assuming quasi-steady flow. Various trim conditions corresponding to elevator trim deflections are explored along a spectrum of freestream angle of attack in aircraft pre-stall regime for said morphing schemes. Based on numerical models, aircraft dynamic modes are discussed providing necessary detail of relevant stability characteristics. Morphing limits for competing design are also investigated from stability perspective. Wing morphing is found to be an imperative control strategy to achieve a versatile set of equilibrium flight conditions. The current study covers the linear dynamics of the aircraft highlighting the phugoid mode instabilities which encourages further implications to be investigated under some suitable nonlinear environment. Moreover, the aerodynamic database generated in this dissertation is useful for designing aircraft Automatic Flight Control System (AFCS) and flight trajectory modeling.
