Dynamic Flight Simulation (DFS) Tool for Nonlinear Flight Dynamic Simulation Including Aeroelastic Effects

Conventional flight dynamic model solves the nonlinear six degrees o f freedom (6-dof) equations of motion with an aerodynamic database to assess the stability, performance and handling quality of the aircraft. This aerodynamic database is usually generated by wind tunnel testing on a rigid aircraft model, whereby the airframe is considered rigid or deformed in qasic-static manner. Dynamic aeroelastic model on the other hand combines the structural dynamics and unsteady aerodynamics to predict the aeroelastic response. However, the equations of motion involved in the dynamic aeroelastic model at least for the structural dynamics, are usually linear, therefore, can not produce the nonlinear response of the fight dynamic model. The need of an integrated flight dynamic model and aeroelastic model is brought ab out by the emerging design requirements for slender, more flexible and/or sizable aircraft such as oblique flying wing, High altitude long endurance aircraft, sensorcraft, and morphing vehicles. In the present work, we have developed a nonlinear dynamic flight simulation (DFS) tool by combining the flight dynamics and aeroe lastic models in a Matlab/Simulink simulation environment. This DFS tool can simulate the key aeroelastic coupling mechanisms between structural dynamic and unsteady aerodynamic effects with the classical rigid-body dynamics. It is formulated in principle by using commonly agreed terms from the flight dynamics and aeroelasticity disciplines. Furthermore, it leaves the flight dynamic model with minimum changes so that D FS remains in the framework of 6-dof simulation environment. Thus, when the aeroelastic effects are removed, DFS reduces to the flight dynamics model.