Low-Reynolds-number lower wing with oblique grooves

Abstract

The invention relates to a low-Reynolds-number lower wing with oblique grooves. A plurality of inclined groove groups which are alternately distributed in a left-inclined manner and a right-inclined manner are arranged near the tail edge of the upper surface; each oblique groove group consists of a plurality of inclined grooves which are arranged in parallel at intervals in the chordwise direction, so that a spanwise array is formed; and the adjacent inclined groove groups are arranged at intervals, so that the plurality of inclined groove groups are integrally zigzag. The inclined grooves are formed in the tail edge of the upper surface of the wing, on one hand, a stable secondary vortex can be formed in the inclined grooves, the effect of a rolling bearing in machinery is achieved, and the effect of reducing viscous resistance is achieved; and on the other hand, the inclined grooves play a role of a vortex generator, secondary flow is formed in the boundary layer of the upper wing surface of the wing, mixing of high-speed flow of main flow and low-speed flow of the boundary layer is enhanced, propagation of the low-speed flow to the main flow is blocked, the capability of resisting reverse pressure gradient is higher, separation of the boundary layer can be restrained, and the lift-drag ratio is effectively increased.

Description

technical field [0001] The invention belongs to the technical field of civil aviation aircraft components, in particular to a low Reynolds number lower wing with oblique grooves. Background technique [0002] With the rise of micro air vehicles and unmanned aerial vehicles, the aerodynamic performance of wings at low Reynolds numbers has attracted more and more attention from researchers. The reduction of the Reynolds number increases the viscous friction on the wing surface. Statistics show that in the cruising state, the frictional resistance of the wall accounts for about 40% of the total resistance; in addition, due to the existence of laminar boundary layer and flow transition phenomenon, the aircraft The boundary layer on the upper surface of the wing is more prone to separation, and the separation will cause serious lift loss. Therefore, for low Reynolds number conditions, it is very important to develop effective flow control methods to suppress flow separation, red...

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Problems solved by technology

[0004]The microstructure of the wall surface represented by the longitudinal small ribs / grooves imitating shark skin has a good performance in the drag reduction of the wall surface, which has attracted extensive attention of researchers However, studies have shown that when the longitudinal small ribs are in the laminar boundary layer, they will generate additional resistance and cannot achieve the effect of drag reduction; the transverse small ribs are considered to be able to play the role of "air bearing" to reduce the friction of the wall, However, it cannot effectively suppress the separation of negative layers, and does not have the effect of reducing drag and increasing lift for wings with high angle of attack

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