Numerical Investigation of the Influence of Fuselage Corner Bluntness on a High-Pressure Capturing Wing Configuration

Abstract

Under beneficial aerodynamic interference, the innovative high-pressure capturing wing (HCW) configuration exhibits remarkable aerodynamic performance at hypersonic speeds. At the same time, the additional lifting surface of the HCW may significantly improve the lift at subsonic speeds, which makes the configuration a promising concept for air vehicle design covering a wide speed range. Recent research has shown that the HCW can generate flow separations on the upper surface of the fuselage in certain subsonic flow conditions, which considerably deteriorates aerodynamic performance of the air vehicle. In this paper, a hybrid configuration combining HCW with a cone-truncated cone fuselage is studied. Numerical simulations are conducted to examine the impact of fuselage corner bluntness on flow characteristics and aerodynamic performances in typical subsonic (Mach 0.7) and hypersonic (Mach 7) flow conditions. The results show that at Mach 0.7, with the increase of blunt radius at the fuselage corner, the flow separations on the upper surface of the fuselage can be effectively restrained. The lift coefficient of the vehicle remains virtually unchanged, while the drag coefficient decreases significantly by 69% when the blunt radius is 600 mm. At Mach 7, the fuselage corner bluntness leads to a slight drop of 9% and 8% in the lift and drag coefficient of the vehicle, respectively, while the lift-to-drag ratio remains virtually unchanged. Hypersonic flight, prized for its potential in long-distance cruising and rapid transportation, is a global research focus. Several hypersonic aircraft concepts have been proposed in recent years, such as the BlueEdge, the Quarterhorse, and the evolving Valkyrie. Aiming for a high lift-to-drag ratio during cruising, the aerodynamic layouts of hypersonic aircraft frequently employ flattened shapes or small-aspect-ratio wings. This results in a significant contradiction between the aerodynamic performance and loading capacity, while it is also difficult for the aircraft to achieve a substantial lift during the subsonic horizontal take-off and landing phase. The contradiction between lift-to-drag ratio and volume has previously been addressed by a new aerodynamic configuration named the high-pressure capturing wing, which adds an upper wing above the airframe. This configuration exhibits remarkable aerodynamic performance at hypersonic speeds under beneficial aerodynamic interference; at the same time, the additional lifting surface may significantly improve the lift at subsonic speeds, making it a promising concept for air vehicle design covering a wide speed range. This paper conducts a numerical investigation on the impact of fuselage corner bluntness on flow characteristics and aerodynamic performances in typical subsonic and hypersonic flow conditions. Obtained results offer references for the design and optimization of the high-pressure capturing wing configuration in a flow field for a wide speed range.