A wedge-shaped diffuser with half-height small vanes

Abstract

The invention discloses a wedge-shaped diffuser with a half-leaf and high-leaflet piece, relates to a radial diffuser of a centrifugal compressor, can adapt to the flow condition of spanwise non-uniform flow, and belongs to the field of design of a pneumatic part of the high-performance centrifugal compressor for a micro-miniature vortex jet engine. The wedge-shaped diffuser with the half-leaf andhigh-leaflet piece comprises an annular disc body, wherein one face of the disc body is a plane, the other face of the disc body is a concave blade cavity, an arc transition chamfer is arranged on the outer edge of the blade cavity, large blades and small blades are arranged on one face of the blade cavity, the large blades and the small blades are circumferentially and alternately arranged at the center of the disc body as the center, and the large blades, the small blades and the disc body are integrally formed for precision casting. The disc body is provided with a runner profile, the runner profile is a diffuser rim profile, the large blades and the small blades are both two-dimensional wedge-shaped straight blades, the modeling mode is consistent, and the blade height, the chord length and the maximum thickness of the small blades are both smaller than that of the large blades.

Description

technical field [0001] The present invention relates to a wedge-shaped diffuser with small blades of half-blade height, which relates to a radial diffuser of a centrifugal compressor, which can adapt to non-uniform incoming flow conditions in the direction of expansion, and belongs to the aerodynamic device of a high-performance centrifugal compressor for a micro turbojet engine. field of component design. Background technique [0002] As an important part of the centrifugal compressor, the wedge diffuser is widely used in small and medium turbojet engines because of its simple structure and convenient processing. With the continuous increase of aircraft's demand for engine thrust-to-weight ratio, the centrifugal compressor is also developing towards higher aerodynamic load, higher aerodynamic efficiency and wider working range. [0003] In a high-load centrifugal compressor, on the one hand, the degree of airflow slippage and flow field structure at different blade heights...

AI Technical Summary

Problems solved by technology

The large positive angle of attack near the blade tip will cause the airflow separation on the suction surface of the blade, resulting in large flow loss; on the other hand, the Mach number of the incoming flow of the diffuser has reached 1.0 or above, and the semi-bladeless diffuser The shock wave will be formed in the region, and the interaction between the shock wave and the boundary layer will further aggravate the development of airflow separation in the diffuser, resulting in a decrease in the diffusion capacity of the diffuser and a reduction in the working range, so it is necessary to design a new Wedge diffuser to better meet the actual needs of use

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