CN203975226U

CN203975226U - A kind of Helicopter Main rotor fin

Info

Publication number: CN203975226U
Application number: CN201420432330.3U
Authority: CN
Inventors: 王志成
Original assignee: Foshan Shenfeng Aviation Technology Co Ltd
Current assignee: Liu Zibing
Priority date: 2014-08-03
Filing date: 2014-08-03
Publication date: 2014-12-03
Anticipated expiration: 2024-08-03

Abstract

A kind of Helicopter Main rotor fin, belongs to vehicle technology field, relates in particular to a kind of helicopter fin.It comprises leading edge, upper surface, lower surface, trailing edge and wing body.Leading edge is abundant perfectly round, upper surface is the curved surface raising up, lower surface is plane or slightly downward protruding curved surface, upper surface chordwise is uniform-distribution with several identical small ruts toward the region of trailing edge from wing thickness, the average depth of each small rut is about 0.25mm, and the diameter of small rut is between 3mm to 8mm; Clear distance between every two adjacent small ruts is between 1mm to 2mm.The sticky fiber yarn of inserting with fine hair in small rut, its length is slightly longer than the half of the diameter of small rut.Wing body is solid construction.Fin is substantially rectangular, and aspect ratio is in 9:1 ~ 13: between 1.The maximum lift-drag ratio of this fin is larger, and effective angle of attack scope is large, and is difficult for stall, and efficiency is high, and noise is low.

Description

A kind of Helicopter Main rotor fin

Technical field

A kind of Helicopter Main rotor fin, belongs to vehicle technology field, relates in particular to a kind of helicopter fin.

Background technology

Traditional Helicopter Main rotor is smooth with the surface of fin, aerofoil profile adopts symmetric form substantially, within the scope of effective angle of attack, can produce lift, but effective angle of attack scope is little, when the angle of attack increases to a certain degree, the air-flow of its upper surface can produce separation, produce stall phenomenon, resistance rises suddenly, and lift declines suddenly; Maximum lift coefficient is little; Because Helicopter Main gyroplane rotate speed is high therefore noise is very large.

Summary of the invention

The object of the invention is to overcome the above-mentioned deficiency of traditional Helicopter Main rotor fin, invent the Helicopter Main rotor fin that a kind of effective angle of attack scope is large, maximum lift coefficient is large and noise is low.

A kind of Helicopter Main rotor fin, comprises leading edge, upper surface, lower surface, trailing edge and wing body.Leading edge is abundant perfectly round, upper surface is the curved surface raising up, lower surface is plane or slightly downward protruding curved surface substantially, upper surface chordwise is uniform-distribution with several identical small ruts toward the region of trailing edge from fin thickness, these small ruts are circular, the average depth of each small rut is about 0.25mm, and the diameter of small rut is between 3mm to 8mm; The difference of the width between centers of every two adjacent small ruts and the diameter of single small rut is between 1mm to 2mm, and the clear distance between two adjacent small ruts is between 1mm to 2mm.The sticky fiber yarn of inserting with fine hair in small rut, its length is slightly longer than the half of the diameter of small rut.Wing body is solid construction.Fin is elongated rectangle roughly, and aspect ratio is in 9:1 ~ 13: between 1.

A kind of Helicopter Main rotor of this invention by the principle of work of fin is: in the time that this fin rotates within the scope of effective angle of attack, it is moving that flow point two plumes are carried out in the front of relative fin, main air is the below air-flow of fin, and this air-flow velocity is substantially constant, suitable with front speed of incoming flow; Secondary air flow is the top air-flow of this fin, and this air-flow upwards flow to thickness and presses close to fin upper surface and turn to back lower place diffluence again turning near the leading edge place of fin.Learn according to the continuity equation of fluid and Bernou1li equation, the top pressure of fin is less than below pressure, thereby produces lift.The small rut of this fin upper surface can make air form the very thin turbulent boundary layer that one deck is close to fin upper surface, even if the angle of attack is larger, due to the effect of small rut, make fin top air-flow to flow to the back lower place along fin upper surface always, be difficult for separating with fin upper surface the generation of small rut deferrable tail.In small rut, the sticky fiber yarn with fine hair of inserting is sound absorption materials, can reduce widely noise.

The main rotor fin of helicopter is not identical with the running environment of the wing of fixed wing aircraft, and the main rotor fin of helicopter moves in a dynamic environment.In the time of the flight of helicopter in hover or vertical direction, the air flow in fin somewhere is to flow downward and contrary tangential horizontal flow synthetic, and fin air flow is the also oblique below of reversing sense of rotating along fin relatively.In the time that helicopter horizontal direction is flown, the air flow in fin somewhere of moving ahead is to flow downward, synthesizing of contrary tangential horizontal flow and backward horizontal flow, that the reversing sense that rotates along fin is also to the left backward relative to fin air flow, to the right or oblique below partially not, directly over helicopter, look down, the rotation of fin anticlockwise direction, on right side from the process at o'clock at 6 o'clock to 12 for moving ahead, from between o'clock at 6 o'clock to 3 relatively fin air flow be oblique below to the left also backward, from between o'clock at 3 o'clock to 12 relatively fin air flow be oblique below to the right also backward, fin in the time of 3 o'clock relative fin air flow to dead aft and oblique below, directly over helicopter, look down, the rotation of fin anticlockwise direction, in left side from the process at o'clock at 12 o'clock to 6 is row, the air flow in rear row fin somewhere is to flow downward, synthesizing of contrary tangential horizontal flow and backward horizontal flow, the component of the contrary tangential horizontal flow of this process in helicopter flight direction is forward, if this component is greater than the speed flying before helicopter, the reversing sense that rotates along fin to the left relative to fin air flow, to the right or oblique below partially not, fin leading edge is done motion windward in this case, the angle of attack fin of adjusting fin can produce lift, the speed flying before if the component of contrary tangential horizontal flow in helicopter flight direction is less than helicopter, the direction of rotating along fin to the left, to the right or oblique below partially not relative to fin air flow, fin trailing edge is done motion windward in this case, leading edge need be raised or forced down to the trailing edge of fin, the angle of attack fin to wind of adjusting fin trailing edge could produce lift.In the time that helicopter climbs, air motion is just more complicated.Require like this angle of fin relative level direction could meet relative wind for positive incidence compared with large and continuous variation, rotating speed speed also needs different adaptation of angle of fin and horizontal direction.And flowing downward of the air of indication be because upper one or more fin swing circles are caused, make air toward current downflow, starting moment does not flow downward; Contrary tangential horizontal flow is because rotatablely moving of fin is caused, the contrary relative fin rotation direction here; Backward horizontal flow is caused owing to flying before helicopter level, is the heading of relative helicopter after herein; All level two words refer to relative level or basic horizontal, are not abswolute levels, because rotor rotating disk relative level face can exist angle.In the middle of reality, to wave the above problem that solves by fin.Can cause like this noise larger.

This fin has following advantage with traditional Helicopter Main rotor compared with fin: 1, effective angle of attack scope is large, and maximum lift coefficient is large, and critical stalling incidence is large, and maximum lift-drag ratio is large; 2, efficiency is high, and weight is lighter; 3, noise is low.

Brief description of the drawings

Fig. 1 is the schematic diagram of a kind of Helicopter Main rotor of the present invention fin; Fig. 2 takes out four adjacent sticky enlarged drawings of inserting the filametntary small rut with fine hair in Fig. 1; Fig. 3 is the aerofoil profile figure through small rut center of a kind of Helicopter Main rotor of the present invention fin.

In figure, 1-leading edge, 2-upper surface, 3-trailing edge, 4-lower surface, 5-wing body, 6-small rut, 7-thickness, the fiber yarn of 8-with fine hair.

Detailed description of the invention

Now 1 ~ 3 couple of the present invention is illustrated by reference to the accompanying drawings: a kind of Helicopter Main rotor fin, comprises leading edge 1, upper surface 2, lower surface 4, trailing edge 3 and wing body 5.Leading edge 1 is abundant perfectly round, the curved surface of upper surface 2 for raising up, lower surface 4 is slightly downward protruding curved surface, upper surface 2 chordwises are uniform-distribution with several identical small ruts 6 from wing thickness 7 toward the Zone Full of trailing edge 3, these small ruts 6 are circular, its degree of depth is 0.25mm, and diameter is 4mm; The clear distance of every two adjacent small ruts 6 is 1.5mm.The interior sticky fiber yarn 8 of inserting with fine hair of small rut 6, its length is about 2.5mm.Wing body 5 is solid construction, adopts carbon fiber composite material to make.The aspect of fin is elongated rectangle roughly, and aspect ratio is 11: 1.Fin root has the hole being connected with propeller hub, not shown in FIG..This fin Use Limitation rate is high, and noise is low.

Claims

1. a Helicopter Main rotor fin, comprise leading edge (1), upper surface (2), lower surface (4), trailing edge (3) and wing body (5), it is characterized in that: leading edge (1) is abundant perfectly round, the curved surface of upper surface (2) for raising up, lower surface (4) is plane or slightly downward protruding curved surface substantially, upper surface (2) chordwise is uniform-distribution with several identical small ruts (6) from wing thickness (7) toward the region of trailing edge (3), these small ruts (6) are circular, the average depth of each small rut (6) is about 0.25mm, the maximum oad of small rut is between 3mm to 8mm, clear distance between every two adjacent small ruts (6) is between 1mm to 2mm, the sticky fiber yarn (8) of inserting with fine hair in small rut (6), its length is slightly longer than the half of the diameter of small rut (6).

2. a kind of Helicopter Main rotor fin according to claim 1, is characterized in that: the degree of depth of small rut (6) is 0.25mm, and diameter is 4mm; The clear distance of every two adjacent small ruts (6) is 1.5mm.

3. a kind of Helicopter Main rotor fin according to claim 1, is characterized in that: in small rut (6), the length of the sticky fiber yarn with fine hair (8) of inserting is about 2.5mm.

4. a kind of Helicopter Main rotor fin according to claim 1, is characterized in that: wing body (5) is solid construction, adopts carbon fiber composite material to make.

5. a kind of Helicopter Main rotor fin according to claim 1, is characterized in that: fin is elongated rectangle roughly, and aspect ratio is in 9:1 ~ 13: between 1.