A Curved Head Double Sweep Close Cone Waverider with Transition Section

Abstract

The invention discloses a curved head double-sweepback osculating cone wave rider with a transition section. The front parts of the wave rider are crossed to form a curved surface head; one front part of the wave rider comprises two straight line sections and a transition curve for connecting the two straight line sections; a first straight line section corresponds to a first sweepback angle from a cusp; a second straight line section corresponds to a second sweepback angle; the angles of the two sweepback angles are controllable in a design procedure; the two straight line sections are connected by the transition curve and a first-order derivative and a second first-order derivative are continued. According to the curved head double-sweepback osculating cone wave rider, a stable separation vortex is generated on an upper surface through the straight line front part with controllable double sweepback angles, so that the aerodynamic performance of the upper surface is improved without reducing the volumetric efficiency of an aircraft, and thus the design of the upper surface is greatly facilitated.

Description

technical field [0001] The invention relates to the field of aerodynamics, in particular to a double-sweep close cone waverider with a curved head and a transition section. Background technique [0002] When an aircraft with a traditional layout flies at hypersonic speed, the maximum lift-to-drag ratio has the following relationship with the flight Mach number: [0003] [0004] where M ∞ is the flight Mach number. It can be seen from the above formula that when the traditional layout is at a high Mach number, the maximum lift-to-drag ratio can only reach about 4, that is, there is a "lift-to-drag ratio barrier". The waverider can break the "lift-to-drag ratio barrier" of the traditional layout. The relationship between the maximum lift-to-drag ratio of the aircraft with the waverider layout and the flight Mach number is: [0005] [0006] The above formula shows that when the waverider layout is at a high Mach number, the maximum lift-to-drag ratio can reach about ...

AI Technical Summary

Problems solved by technology

In this flow field, the lower surface flow is limited by the attached shock wave without leakage to the upper surface, whereas for conventional layouts, this upper and lower surface leakage can result in up to 25% lift loss

Although the generation and design methods of waveriders have been deeply studied, there are still the following problems: 1. The volumetric efficiency and lift-to-drag ratio are contradictory, which must be weighed during design; Aerodynamic performance but lower volume efficiency. Designing a compression surface can improve volume efficiency but reduce aerodynamic performance. At present, it is generally designed as a free flow surface, which does not contribute to aerodynamic performance and volume efficiency; 3. Non-design state, especially low-speed performance is poor , because the waverider can only ride waves in the design state

However, due to the small plane area of ​​this shape, the lift increase it brings is limited, and the low-speed performance is not good, the resistance is large, and the take-off and landing performance is very poor.

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