Flow Field Interference Characteristic of Axial Ring Wing Configuration

Article history: Received: 25.10.2014. Received in revised form: 19.03.2014. Accepted: 20.03.2014. To analyze the air flow interference between upper and lower wings in axial ring wing configuration, NASA SC(2)-1006 supercritical airfoil is chosen as the basic airfoil. Flow field around the doublewing structure with different relative distances between upper and lower wings is numerically simulated, using SST k   turbulence model, and the numerical conclusion about the influence of relative distance D/L on the aerodynamic performance is drawn. It is shown that, at the speed Ma = 0.8, reflection of shockwave between the upper wing and the lower wing has a great negative effect on both lift and drag coefficient. When D/L = 0.1, and the angle of attack AOA = 0°, the resultant lift produced by the two wings is equivalent to that of the single wing, while the resultant drag is 4 times of that of the single wing, which shows a poor aerodynamic characteristic. With the increasing of the relative distance, the intensity of the shockwave between the upper and lower wings is weakened and the negative effect is relieved. Furthermore, the growth of the angle of attack AOA can obscure the negative effect. It could provide helpful reference to the design of axial ring wing aircraft.