Bump air inlet method for realizing integration of unequal-strength wave system with forebody

Abstract

The invention provides a bump air inlet method for realizing integration of an unequal-strength wave system with a forebody, relating to the technical field of ultrasonic air inlet. The method comprises the following steps that: 1, an air inlet wave system adopts an external-compression double wave system structure based on an unequal-strength system, and the total pressure recovery coefficient sigma=sigma1*sigma2, wherein the sigma1 and the sigma2 are total pressure recovery coefficients of a conical shock wave and a normal shock wave; 2, a cone with a semi-cone angle delta c formed by the conical shock wave generates a second conical shock wave with second semi-cone angle beta in ultrasonic flow; 3, the bump height of the air inlet is h, the h / delta is 2-2.5 when the local boundary layer thickness is delta, the bump compressive plane generated in the step 2 is scaled to meet the requirement of an actual size; and 4, the lip of the air inlet adopts a conformal and sweepback lip design. The method realizes reduction of throat Mach number of the air inlet, improves the air inlet performance to ensure that the lip sweepback angle of the air inlet, the maximum turning angle of the bump compressive plane and the inlet normal shock wave angle are consistent, can increase the curve of the total pressure recovery coefficient, and reduces resistance coefficient.

Description

technical field [0001] The invention relates to a bump inlet design integrated with a front fuselage based on unequal-intensity wave systems, and belongs to the technical field of supersonic inlets. Background technique [0002] The design of the air intake is one of the keys to the design of a fighter. The air inlet must not only provide sufficient high-quality air for the engine in all states, but also consider the constraints of the overall layout and the requirements of the integrated design during design. In addition, it must also meet the overall stealth requirements of the fighter. For the supersonic inlet, it is necessary to pass a series of shock waves to decelerate the supersonic incoming flow into subsonic flow, continue to decelerate and diffuse in the diffuser channel, and then flow to the engine. The traditional supersonic inlet design generally adopts compression slant plate or compression cone to form a shock wave system, and lifts the inlet of the inlet awa...

AI Technical Summary

Problems solved by technology

[0005] However, domestic and foreign attention to the bump inlet is mainly focused on the design of the three-dimensional bulging compression surface. The published literature has not paid attention to the integrated design of the bump inlet and the front fuselage of the aircraft, and has not given the relevant integrated design. Parameter Selection Principles

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