Invisible snakelike air inlet channel design method based on matrix transformation

Abstract

The invention discloses an invisible snakelike air inlet channel design method based on matrix transformation. According to the technical scheme, when the center line is designed, front and rear sections of quintic polynomials are spliced, so that the whole center line is second-order continuous; in the aspect of shape design of the cross sections of the pipeline, the contour line of each cross section is dispersed into a plurality of points, coordinates of the points are sequentially listed in the clockwise direction, and the contour line of each cross section can be represented by a matrix. Based on the method, the geometric shape change of the cross section contour line is converted into algebraic operation between matrixes. By designing a matrix transformation rule among an inlet section, a middle section and an outlet section, a shape change rule of a cross section contour line can be designed. By means of the design method, smooth transition between sections in any shape can be achieved, the starting point and the end point of each section curve generated in the design process are located on the symmetry plane, and therefore the more accurate air inlet channel profile can be obtained.

Description

technical field [0001] The invention belongs to the technical field of air inlets of aircraft, and in particular relates to a design method of a stealth serpentine air inlet. Background technique [0002] As an important component of the aircraft propulsion system, the air intake is located upstream of the aero-engine, and is responsible for capturing the flow and adjusting the airflow quality for the downstream engine. From the point of view of geometric features, the intake port is essentially a pipe with a variable cross-section. With the increasing complexity of the battlefield environment, the requirements for the stealth performance of the aircraft are getting higher and higher, and in order to reduce the radar scattering area of ​​the engine as much as possible, it is required that the intake duct be bent in an "S" shape according to a certain rule, so as to realize the protection of the engine. occlude. The design of conventional variable-section curved pipes mainl...

AI Technical Summary

Problems solved by technology

The present invention can solve the technical problem that the air inlet designed in the prior art is difficult to smoothly transition between the inlet section, the intermediate control section and the outlet section, and no matter how many points the contour line of the cross section is discretized, each intermediate transition The sections are all generated by strict mathematical operations, and there is no approximate operation. In addition, it can also solve the technical problem of gaps at the symmetry planes in the intermediate transition sections designed in the prior art.

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