Leading-edge slat with drainage groove and designing method of drainage groove

Abstract

The invention relates to a leading-edge slat with a drainage groove and a designing method of the drainage groove. By designing the drainage groove with a certain geometric shape, a wide inlet formed in the lower surface and a narrow outlet formed in the upper surface in the leading-edge slat, and by utilizing the pressure difference of the upper and lower surfaces of the leading-edge slat, an air flow with high pressure of the lower surface of the leading-edge slat is introduced into the upper surface of the leading-edge slat by virtue of the drainage groove and is blown out along the tangential direction of the upper surface of the leading-edge slat for blowing down a low-energy air flow piled on the upper surface of the leading-edge slat, repairing a damaged speed type of a boundary layer, lowering the thickness of the boundary layer and improving the ability of the boundary layer to resist adverse pressure gradient, and thus, separation of the air flow, around the leading-edge slat, is delayed, the stalling process of an aircraft is slow, variation of the aircraft lift after stalling is mitigated, and the stalling characteristic of the aircraft is alleviated. According to the invention, the leading-edge slat is applied to some civil aircraft and is capable of postponing the stall angle alpha stall of an aircraft body combination of equal-chord swept back wings of the aircraft by 1 degree when the aircraft is in a typical takeoff / landing state with the flight speed being mach number 0.20 and turning the aircraft into slow stalling from sudden stalling, and the lift variation after stalling is small, so that the stalling prewarning time is effectively prolonged, and the flight safety is improved.

Description

technical field

[0001] The invention relates to the field of aircraft design, in particular to a design method for a leading edge slat with drainage grooves and the drainage grooves. Background technique

[0002] The combination of leading edge slats, main wing sections and trailing edge flaps is the main method for modern aircraft to obtain high lift to complete the takeoff / landing process. Among them, the main function of the leading edge slat is to delay the separation of the airflow on the wing, so that the aircraft will stall only at a larger incoming flow angle of attack, thereby increasing the stall angle of the aircraft (stall angle of attack refers to the maximum lift. Corresponding incoming flow angle of attack), increase the maximum lift of the aircraft, enhance the loading capacity of the aircraft, and expand the flight boundary.

[0003] Since the main function of the leading-edge slat is to delay the stall of the aircraft, the flow characteristics of the leadi...

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