Research on dynamic aerodynamic characteristics of flying wing model with low aspect ratio

Abstract

The flying wing with low aspect ratio removes the horizontal and vertical tails and adopts configuration of wing-body fusion, which has better lift and drag characteristics and stealth than the traditional wing-body split configuration. In this paper, with the help of the semi-reflux transient transonic wind tunnel of China Aerodynamics Research and Development Center, a single-degree-of-freedom pitching dynamic force test is carried out on the standard model of flying wing with low aspect ratio, and the mechanism of some cases is analyzed through numerical calculation. The study found that when the fuselage is forced to pitch at f=1Hz: The normal force coefficient curve will form a hysteresis loop in the shape of a spoon; during the pitching process, the angle of attack of stall is delayed from the 40° which is the angle of attack of stall in static case to 45°; the pitching movement will delay the dissipation of the energy of leading edge vortex along the flow direction and increases the vortex suction at the rear of the wing; the flow pattern of the suction surface is similar during the upward elevation process, and spanwise flow is more severe than the static case under the same angle of attack.