Research On The Flowfield And Aerodynamic Characteristics Of Canard Rotor/wing Aircraft

In this thesis, the Canard Rotor/Wing (CRW) Aircraft is selected as the object of study. In response to the complicated characteristics of its flowfield, a CFD numerical simulation method for the CRW flowfield is established based on the momentum source model. By this method, the characteristics of CRW flowfield in hover and forward flight are investigated. Also, preliminary investigations are conducted to simulate the flowfield of CRW at transition state. The major research work in the thesis is as follows:As the background of the current work, Chapter 1 briefly introduced the research results on the flowfield and aerodynamic characteristics of CRW. It is pointed out that the CFD method based on the momentum source model is necessary for the research of CRW flowfield.In Chapter 2, based on the Jameson finite volume method and the momentum source model which is used to consider the effects of CRW blades on their flow field, a numerical method and computer code suitable for solving the flowfield and aerodynamics characteristics of CRW is developed. Then, the simulation of isolated fuselage and rotor flowfield is performed and the calculated results are compared with the available experimental data to demonstrate the validation of the method.In Chapter 3, a mesh-generation approach around the CRW aircraft is given by considering the geometry characters of CRW and the momentum source model.In Chapter 4, by the above numerical simulation method, the analysis on the CRW flowfield in hover is made, and the flowfield and aerodynamic characteristics of CRW with different design parameters are investigated. Based on the above investigation, some meaningful results are obtained.In Chapter 5, on the basis of hover flowfield, the CRW flowfield in airplane mode with different forward velocties are calculated and the effects of the forward velocities on CRW flowfield are analyzed. Then, the effects of different airfoil on the flowfield and aerodynamic characteristic of its tail are calculated which supplies the reference data for the selection of CRW tail airfoil.In Chapter 6, based on the above work, the simulation of CRW flowfield in transition state is tried, the flowfield with different positions of the wing and rotor is calculated respectively. The characteristics of these different flowfield are analyzed.