Experimental Research on Aerodynamic Characteristics of Large Aspect Ratio Wing in Unfolding Process

For an unmanned aerial vehicle, in order to study the aerodynamic characteristics of the large aspect ratio wing during the deployment process with variable sweep angles, the scaled model was tested in the wind tunnel at different angles of attack with various sweep angles of wing. Experimental results indicate that the aerodynamic configuration satisfies the cruise design requirements, providing favorable longitudinal and lateral-directional stability. Fuselage of multi-plane combination brings beneficial effect for lift. Analysis have been made on the cases including wing flow separation which lead to the step of lift curve, and the existence of longitudinal unstable range during wing unfolding, which make the foundation for next optimum of configuration. The work described in this paper can be applied in the design of unmanned aerial vehicles, missiles and other research areas.