Investigation of the unsteady aerodynamic characteristics of a fighter with complex configuration undergoing yaw-roll coupling oscillation motion

A new set of double degree of freedom in volatile test system is designed and con-structed in FL-8 wind tunnel.The test apparatus can not only simulate aircraft′s single degree of freedom maneuver,but also realize yaw-roll coupling movement and pitch-roll coupling move-ment around the body axis.This paper introduces the experimental proj ect in detail and conducts research into the time history influence when the model is maneuvering.Afterwards the influence of the coupling factor on the unsteady aerodynamic characteristics undergoing yaw-roll coupling oscillation motion is analyzed quantitatively at the oscillation equilibrium position.The results in-dicate that the unsteady aerodynamic gained undergoing yaw-roll coupling oscillation motion is e-qual to the linear superposition of the unsteady aerodynamic gained in the test of single yaw and roll motions when the angle of attack at the equilibrium position is less than the stall angle of at-tack.The influence of the coupling factor on the unsteady aerodynamic is remarkable near the stall angle of attack.The influence of the coupling factor on the unsteady aerodynamic is weak when the angle of attack at the equilibrium position is much greater than the stall angle of attack.