CN201159202Y - A kind of compressed air motor blade tiplet - Google Patents

Abstract

A compressor motor blade tiplet relates to the field of turbomachinery. The blade tiplet is mainly composed of a leading edge wing, a pressure surface wing, a suction surface wing and a trailing edge wing. The pressure surface wing and the suction surface wing are formed on the compressor motor blade On the basis of the profile of the airfoil, the small airfoils extending in the circumferential direction between the leading edge point A and the trailing edge point B of the airfoil, and the leading edge points D and C of the pressure surface airfoil and suction surface airfoil are located on the compressor blade The leading edge point A of the profile or between the leading edge point A and the maximum thickness of the airfoil, the trailing edge points F and E of the pressure surface airfoil and the suction surface airfoil are located at the trailing edge point B of the compressor rotor blade profile or between the trailing edge point B and the Between the maximum thickness; both the leading and trailing airfoils are smoothly connected to the suction and pressure airfoils, and both the leading and trailing edge airfoils are extensions of the suction and pressure airfoils at the leading and trailing edges . The utility model has the beneficial effects of reducing blade tip leakage, reducing the influence of blade tip leakage vortex and friction vortex on the flow field in the flow channel, improving the blade cascade flow field and increasing the efficiency of the compressor.

Description

A kind of compressed air motor blade tiplet

technical field

The utility model relates to the field of impeller machinery, in particular to the design of blade tip winglets applied to various compressor blades.

Background technique

In the compressor, the geometric dimension of the tip clearance between the top of the moving blade and the casing is very small compared with the entire flow path, but it affects the flow of nearly 20% of the blade flow path, especially In a compressor with a relatively small size, the tip clearance has the following adverse effects: 1) The existence of the tip clearance will reduce the actual flow of the working fluid, resulting in a decrease in the work of the working fluid near the tip, channel blockage and cascade The loss increases; 2) The tip leakage will form a tip leakage vortex on the suction surface of the moving blade, and the tip leakage vortex interacts with the channel vortex, making the flow in the cascade channel more complicated, increasing the flow loss, and changing the air outlet angle; 3) Due to the movement of the rotor relative to the casing wall, the frictional movement of the boundary layer on the casing wall is caused to form a friction vortex. The three effects brought by the blade tip clearance all change the flow field distribution in the compressor cascade to varying degrees and increase the flow loss of the air flow in the compressor. The flow loss caused by the tip clearance and the secondary flow loss such as the tip leakage vortex and the tip friction vortex generally account for a considerable proportion of the total loss of the compressor, and their increase will lead to an increase of the total loss of the compressor. If a blade shroud is used on the top of the moving blade, the blade shroud and the outer casing must adopt a multiple sealing system, and the blade shroud rotates at a high speed, and the centrifugal force is relatively large, which will increase the stress on the moving blade, thereby reducing the compressor to a certain extent. work reliability.

Contents of the invention

The purpose of this utility model is to provide a design of blade tip winglets applied to various compressor motor blades. This design can reduce blade tip leakage, reduce the impact of blade tip leakage vortex and friction vortex on the flow field in the flow channel, and at the same time improve The cascade flow field improves the efficiency of the compressor and broadens the stable working range of the compressor.

In order to achieve the above object, the technical scheme of the utility model is as follows:

A compressor motor blade tiplet is mainly composed of a leading edge wing 4, a pressure surface wing 3, a suction surface wing 5, and a trailing edge wing 1 or a trailing edge wing 6. The tiplet 7 is mainly used for a compressor motor blade 8, Its installation position is the top of the rotor blade, and the connection method can be processed integrally with the rotor blade, or the blade tip winglet can be processed separately, and then connected to the rotor blade by welding or other methods; The connection transition can be chamfered transition, rounded transition or smooth transition with free-form surface; the pressure surface wing 3 and the suction surface wing 5 can be used alone or in combination with other parts of the winglets. When used in combination, each winglet It can be processed integrally, or processed separately, and then connected by welding; the suction surface wing 5 and the pressure surface wing 3 are based on the profile of the compressor motor blade, at the leading edge point A and the trailing edge point The airfoils extending along the circumferential direction between B; the leading edge point C and leading edge point D of the suction surface wing 5 and the pressure surface wing 3 are located at the leading edge point A of the compressor rotor blade profile or the leading edge point A is at the maximum distance from the blade profile Between the thicknesses, the trailing edge point E and the trailing edge point F of the suction surface airfoil 5 and the pressure surface airfoil 3 are located between the trailing edge point B or the maximum thickness of the airfoil and the trailing edge point B, and the suction surface airfoil 5 or the pressure surface airfoil 3 The optimal positions of the leading edge point and the trailing edge point of the slab need to be determined by calculation and experiment according to the actual demand; the width of the suction surface wing 5 and the pressure surface wing 3 can be the same or different from the leading edge to the trailing edge, and the shape can be regular The shape can also be the irregular shape of the free-form surface structure; the leading edge wing 4 and the trailing edge wing are connected smoothly with the suction surface wing 5 and the pressure surface wing 3, and the leading edge wing 4 and the trailing edge wing 1 or the trailing edge wing 6 are suction The extensions of the wing 5 and the pressure wing 3 at the leading edge and the trailing edge are generally a smooth structure with a free-form surface, and the trailing edge wing can also adopt a dovetail structure. The top of the tiplet has the same curvature as the outer casing to ensure a small uniform distance between the tiplet and the outer casing during operation, reducing airflow leakage from the pressure surface to the suction surface. The clearance control between the top of the tiplet and the outer casing can be controlled by active clearance control or passive clearance control according to the design requirements, and a layer of wear-resistant coating can also be applied on the inner wall of the outer casing, and on the tip of the tiplet Abrasion resistant material is added to the top to control leakage losses between the outer case and the top of the tip winglets.

The beneficial effects of the utility model are: the design of the blade tip winglets is adopted on the top of various compressor motor blades, which has the functions of reducing the blade tip leakage, controlling the blade tip leakage vortex and the friction vortex, and at the same time can improve the flow of fluid from the blade root to the blade root. The secondary flow field formed by the blade tip series flow improves the efficiency of the compressor and widens the stable working range of the compressor. Compared with the blade shroud, the utility model has the advantages of simple structure, light weight and high reliability.

Description of drawings

Fig. 1 is the top view of the utility model compressor motor blade and the blade tip winglet with leading edge wing and smooth structure trailing edge wing.

Fig. 2 is a top view of the utility model compressor motor blade and the blade tip winglet with leading edge wing and dovetail structure trailing edge wing.

Fig. 3 is a three-dimensional view of the compressor motor blade and the blade tip winglet of the utility model.

Fig. 4 is a cross-sectional view of the compressor motor blade and the blade tip winglet along the flow direction of the utility model.

Fig. 5 is a schematic diagram of the structure of the blade tip flow field without the blade tip winglet.

Fig. 6 is a schematic diagram of the structure of the blade tip flow field with the blade tip winglet of the present invention.

In the figure: 1. Smooth structure trailing edge wing, 2. Blade contour line, 3. Pressure surface wing, 4. Leading edge wing, 5. Suction surface wing, 6. Dovetail structure trailing edge wing, 7. Tiplet winglet , 8, air compressor moving blade.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described in further detail:

As shown in Figures 1 to 4, the utility model compressor motor blade tiplet is mainly composed of leading edge wing 4, pressure surface wing 3, suction surface wing 5 and trailing edge wing, suction surface wing 5 and pressure surface wing 3 It is a small airfoil extending along the circumferential direction between the leading edge point A and the trailing edge point B on the basis of the airfoil profile of the compressor motor blade, and the leading edge point C of the suction surface wing 5 and the pressure surface wing 3 and the leading edge point D are located at the leading edge point A of the compressor blade profile or between the leading edge point A and the maximum thickness of the blade profile, the trailing edge point E and the trailing edge point F of the suction surface wing 5 and the pressure surface wing 3 are located at the The trailing edge point B of the blade profile or between the trailing edge point B and the maximum thickness of the blade; both the leading edge wing 4 and the trailing edge wing are smoothly connected with the suction surface wing 5 and the pressure surface wing 3, and the leading edge wing 4 and the trailing edge wing Both are extensions of the suction surface airfoil 5 and the pressure surface airfoil 3 at the leading edge and the trailing edge.

As shown in Figure 5, in the normal tip flow field without tiplets, the high-pressure fluid on the pressure side flows to the low-pressure area on the suction side, and a friction vortex is easily formed on the outer casing wall on the pressure side. The high-speed jet fluid formed by leaking through the tip clearance on the face side will form a tip leakage vortex at the tip of the suction side, which may interact with the end wall boundary layer to form a large-area separation.

As shown in Figure 6, in the blade tip flow field using the blade tip winglet, there is a secondary flow flowing from the middle of the rotor blade to the blade tip due to the channel vortex on the pressure surface side. When the winglet is tipped, the airflow is forced to turn, which is opposite to the direction of the leakage fluid flowing from the pressure side to the suction side, and the two interact to weaken the tip leakage. increases, the frictional resistance increases, the flow rate of the leakage fluid decreases a lot, and the leakage flow decreases a lot, which also controls the influence of the leakage vortex on the suction side to a certain extent.

Claims (5)

1, a kind of blade tip alula of gas-pressing automotive leaf, it is characterized in that, this tip vane is mainly by the leading edge wing (4), the pressure side wing (3), the suction surface wing (5) and the trailing edge wing are formed, the suction surface wing (5) and the pressure side wing (3) are on the basis of gas compressor moving blade blade profile profile, the little fin that between blade profile leading edge point A and trailing edge point B, along the circumferential direction expands, the leading edge point C of the suction surface wing (5) and the pressure side wing (3) and leading edge point D are between gas compressor moving blade blade profile leading edge point A or leading edge point A and blade profile maximum ga(u)ge, and the trailing edge point E of the suction surface wing (5) and the pressure side wing (3) and trailing edge point F are between gas compressor moving blade blade profile trailing edge point B or trailing edge point B and blade profile maximum ga(u)ge; The leading edge wing (4) and the trailing edge wing all with the suction surface wing (5) and smooth connection of the pressure side wing (3), the leading edge wing (4) and the trailing edge wing all are the extensions at leading edge place and trailing edge place of the suction surface wing (5) and the pressure side wing (3).

2, a kind of blade tip alula of gas-pressing automotive leaf as claimed in claim 1 is characterized in that, the described trailing edge wing is for adopting the smooth structure trailing edge wing (1) or the dovetail structure trailing edge wing (6) of free form surface.

3, a kind of blade tip alula of gas-pressing automotive leaf as claimed in claim 1 is characterized in that, the described suction surface wing (5) and the pressure side wing (3) width along its leading edge to trailing edge is identical or different, and it is shaped as the irregularly shaped of regular shape or free form surface structure.

4, a kind of blade tip alula of gas-pressing automotive leaf as claimed in claim 1 is characterized in that, the Placement of described tip vane and gas compressor moving blade adopts chamfering transition, round-corner transition or adopts the free form surface smooth transition.

5, the described a kind of blade tip alula of gas-pressing automotive leaf of claim 1 is characterized in that, the described suction surface wing (5) and the pressure side wing (3) use separately or be used in combination with other winglet.

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