Design and Experiment of Lift Transfer in Scheme of High-Speed Helicopter

With the development of helicopter in military and civil aviation,it is necessary to increase its flight speed. The research in this filed has been done for long time. So many projects in scheme of high speed helicopter are presented in recent years. However, every project must solve a problem related to main rotor stall and shock wave-the reasons that restrict the forward speed of the helicopter.Most of the projects solve this problem by lift transfer,that is, to shift the lift from the main rotor in the helicopter model to the wing in the air plane model.In the schemes, the project of rotor/wing interchanging model is most hopeful. The key technique of the project of the high speed rotorcraft is the smoothness of lift shift,power and control. In this paper, the process of the lift shift is designed. To verify the feasibility of the scheme, the wind tunnel experiment is needed. The especial model of the diskwing/co axial rotors, or DCAR and a test rig are designed and built. The lift and the power are measured in different wind speeds, rotate speeds, attack angles for the diskwing and the DCAR. Based on these test data, the calculation method is revised for aerodynamic characteristics of the DCAR.Then,the feasibility of the lift shift for the DCAR is proved.