Research On Morphing Aerodynamics Characteristics And Control Of Morphing Aircraft Based On CFD

The morphing aircraft is a new kind of aerocraft in new concept. Compared with the general fixedwing aircraft, it has many advantages. The research program of morphing aircraft is begun at an earlytime in Europe and American. The programs of it are also developed at home. The technology ofmorphing aircraft has great significance in the application of aviation. With the method ofComputational Fluid Dynamics (CFD), the control problem of deformable camber morphing aircraftis researched and the deformation control of stability and maneuverability is completed in this thesis.Firstly, the basic knowledge of CFD, FLUENT software and simulation of numerical computationare introduced. The mesh model of morphing airfoil is built in the Gambitt which is front-endprocessing software of FLUENT. The phenomenon of shockwave on the surface of airfoil is capturedin the process of numerical simulation in FLUENT.Then, the aerodynamics data of morphing airfoil is analyzed in the different kinds of conditions.Choosing an appropriated set of data, the function relationship between aerodynamics parameters andcamber of morphing airfoil is acquired by the use of interpolation polyfit. In addition, the functionrelationship of morphing aircraft is estimated and amended.At last, the parameter-variable system model of morphing aircraft is built and the state equationwith variable parameter of camber is obtained based on the function relationship of morphing aircraft.By using the theory of Robust Optimal Control, The Robust Optimal LQ control law of uncertaintysystem is designed for the morphing aircraft system. The deformation stability control of morphingaircraft is firstly researched. The simulation results indicate that the flight velocity, height and flightquality are maintained, and the equilibrium point of morphing aircraft system is changed into new one.The influence on morphing aircraft system is compared with different deformation rate. At the sametime, the deformation maneuverability control is researched, and the simulation results indicate thatnot only the flight climb maneuver is realized, but also the flight velocity and height are maintained.On the other hand, the advantages of deformation stability and maneuverability control are analyzed.