CN102459916A

CN102459916A - Centrifugal impeller for a compressor

Info

Publication number: CN102459916A
Application number: CN2010800249368A
Authority: CN
Inventors: 杰罗姆·波罗多; 尼古拉斯·罗绰恩; 劳伦特·塔诺斯基
Original assignee: Turbomeca SA
Current assignee: Safran Helicopter Engines SAS
Priority date: 2009-06-05
Filing date: 2010-06-02
Publication date: 2012-05-16
Anticipated expiration: 2030-06-02
Also published as: EP2438306B1; JP5705839B2; RU2011153687A; KR20120034670A; EP2438306A1; KR101750121B1; FR2946399A1; JP2012528979A; US20120087800A1; RU2525365C2; CA2762308A1; PL2438306T3; FR2946399B1; WO2010139901A1; CN102459916B

Abstract

The invention relates to a centrifugal impeller for a compressor, through which a fluid is to pass, said impeller (18) including blades (24, 25), each having a leading edge and a trailing edge (24F, 25F), the rotation of said impeller (18) drawing the fluid at the front of the impeller, said fluid being discharged at the outer periphery of the impeller (18) at the trailing edge (24F, 25F) of the blades, said blades (24, 25) being such that, in a radial cross-section intersecting the trailing edge (24F, 25F) of the blades, the latter are curved in a direction opposite to that of the rotation of the impeller and the trailing edge portion of said blades (24, 25) is straightened in the impeller rotation direction such that it forms an end fin (26, 27) for diverting the fluid flow by radially adjusting same.

Description

The centrifugal impeller that is used for compressor

Technical field

The centrifugal impeller that the present invention relates to make fluid, particularly gas to pass through.Said impeller is especially for turbomachine compressor.Said impeller can be mounted to and be used for fixing or the turbo machine of any kind of the purposes of flying, and particularly is assembled on the helicopter turbine engine.

More particularly, the present invention relates to such centrifugal impeller, it has running shaft, the forward part of small bore and heavy in section rear section, and said impeller has blade, and each blade has leading edge and trailing edge.The rotation of said impeller makes fluid suck via the front portion of said impeller, and the axial velocity of passing the fluid of said impeller is changed into radial velocity gradually, and said fluid leaves said impeller at said vane trailing edge place via the outer periphery of said impeller.Said blade makes in the radially cutting plane that intersects with said vane trailing edge, and the said blade edge direction opposite with the sense of rotation of said impeller is crooked.

Background technique

In this application, term " upper reaches " and " downstream " define with respect to the normal direction that the fluid through impeller flows.

And the running shaft of impeller often is called " impeller shaft " more simply.Axial direction, and the direction that radially is perpendicular to said axle and intersects with said axle corresponding to impeller shaft.Similarly, axial plane is the plane that comprises impeller shaft, and the radial plane is perpendicular to the plane of said axle.Adverbial word " axially " and " radially " are meant respectively vertically and radially.

Only if indicate contrary, otherwise adjective " interior " and " outward " be with respect to radially using, and the interior part of an element (that is, radially interior part) more approaches impeller shaft than the exterior portions of similar elements (that is, radially exterior portions).

At last, only if indicate contrary, otherwise adjective " preceding " and " back " reference axis be to use, and fluid gets into through the front portion of impeller.

The flight turbo machine (for example; The turbo machine of helicopter turbine engine) compressor is centrifugal type or axial-centrifugal mixed type; Comprise one or more compression stages; Have the centrifugal impeller (also being called as centrifugal wheel or rotor) of the above-mentioned type, surround the housing of impeller blade in the outside and be positioned at one or more diffusers in impeller downstream.Fluid (gas is generally air) passes such compressor.

In impeller, the absolute velocity of gas is owing to CENTRIFUGAL ACCELERATING increases, and the pressure of gas increases owing to the cross section of dispersing of the passage that between impeller blade, limits.Like this, gas leaves the downstream of blade, i.e. their trailing edge with flank speed.

The known example that is used for the centrifugal impeller of compressor discloses at U. S. Patent 3 973 872.

Summary of the invention

The objective of the invention is to,, improve the performance (that is, overall pressure ratio and isentropic efficiency) of the above-mentioned type impeller for given physical dimension and correction back flow velocity.

This purpose realizes through a kind of impeller; Wherein, In the said radially cutting plane that the trailing edge with impeller blade intersects, said vane trailing edge part (that is, being positioned at the part of the outer end of blade rear section) is along the sense of rotation changed course of said impeller; Forming corresponding end fin, thereby flowing of fluid can be deflected owing to radially altering course.

Usually, the mobile such deflection of fluid can make overall pressure ratio increase, and can not reduce the isentropic efficiency of impeller.

And, through obtaining better control, can under situation about not heating up, increase overall pressure ratio to this deflection.Like this, the increase of overall pressure ratio also makes the isentropic efficiency of impeller increase more or less.

In a word, the end fin is used to improve the performance of impeller.

The impeller that is used for compressor like this can have two types blade: alleged " master " blade and alleged " centre " blade.Optional intermediate blade is between primary blades, and the difference of they and primary blades is that intermediate blade is shorter vertically: intermediate blade has short forward part, and the leading edge of intermediate blade is with respect to the leading edge withdrawal (promptly backward) of primary blades.

In one embodiment, impeller only has primary blades (promptly not having intermediate blade), and primary blades has the end fin of aforementioned type.

In another embodiment, impeller has primary blades and intermediate blade.In this case, it is the blade with end fin of aforementioned type that primary blades is only arranged, and it is the blade with end fin of aforementioned type that intermediate blade is perhaps only arranged, and perhaps primary blades and intermediate blade all have the end fin of aforementioned type.

In one embodiment, in the said radially cutting plane that the trailing edge with impeller blade intersects, said end fin cooperates with the blade-section that is positioned at said end fin upper reaches close vicinity, to form more than or equal to 155 ° and strict obtuse angle less than 180 °.

In one embodiment; When the primary blades of impeller has the end fin; Length when end fin (curve) outward edge from the trailing edge extend through of impeller primary blades along primary blades is measured; Said length is rendered as less than 15% of said outer peripheral total length, particularly greater than said outer peripheral total length 2% and less than 10% of this total length.

In one embodiment; When the intermediate blade of impeller has the end fin; The length when outward edge of said end fin from middle vane trailing edge extend through along intermediate blade measured; Said length is rendered as less than 15% of said outer peripheral total length, particularly greater than said outer peripheral total length 2% and less than 10% of this total length.

The scope of aforesaid angle value and fin length is used for further improving the performance of impeller individually or in combination.

The invention still further relates to a kind of compressor that comprises centrifugal impeller of the present invention.Said compressor can be the compressor of centrifugal type; The compressor that promptly has at least one compression stage that is equipped with centrifugal impeller; Or be the compressor of axial-centrifugal mixed type, promptly have at least one compression stage that is equipped with axial impeller and the compressor that is equipped with at least one compression stage of centrifugal impeller.

The invention still further relates to a kind of turbo machine, relate more particularly to a kind of helicopter turbine engine that comprises compressor of the present invention.

Description of drawings

Following to utilizing the detailed description of the embodiments of the invention that the non-limiting example mode provides through reading, the present invention and advantage thereof are better understood.Reference will be made to the accompanying drawings.

Fig. 1 is the schematic local axial cross section (centrifugal impeller and engine turbine do not show with sectional view, but show with side view) with helicopter turbine engine of the compressor that comprises centrifugal impeller of the present invention.

Fig. 2 is the schematic representation of the centrifugal impeller shown in Figure 1 that separates with the engine remaining part.

Fig. 3 is the schematic partial perspective view of rear section that demonstrates two blades of centrifugal impeller shown in Figure 1.

Fig. 4 is the schematic partial view of the rear section of one of blade shown in Figure 3, wherein demonstrates sectional view with the radially cutting plane that intersects with trailing edge, and this cutting plane IV-IV marks in Fig. 2.

Embodiment

Exemplary helicopter turbine engine 10 shown in Fig. 1 comprises: the compressor 16 of centrifugal type, it has single compression stage.Compressor 16 comprises: the housing 15 in

blade

24,25 outsides of centrifugal impeller 18 of the present invention and encirclement impeller 18.One diffuser 19 is positioned at the downstream of impeller 18.

Engine 10 has: air inlet 12, the air that passes said inlet 12 arrives compressor 16.Impeller 18 makes air suck via the front portion of impeller around the rotation of its running shaft A, and the axial velocity of passing the fluid of impeller 18 is changed into radial velocity gradually, and fluid leaves impeller 18 through the outer periphery of impeller 18.Air penetrates in the impeller 18 along the direction that is roughly parallel to impeller rotating shaft A, as in the cross section of Fig. 1 by shown in the arrow F1, air leaves impeller 18 along the direction that is approximately perpendicular to an A, as by shown in the arrow F2.

The air that leaves impeller 18 passes diffuser 19, arrives firing chamber 20 then.Leave the combustion gases drive high-pressure turbine 22 and low-pressure turbine 23 of firing chamber 20.

Impeller 18 is installed on the axle 21 that is driven by high-pressure turbine 22 rotations.

Referring to Fig. 2, impeller 18 has: the forward part of small bore and heavy in section rear section.Impeller 18 has a plurality of

primary blades

24, and 18A extends to the radial plate 17 at the rear portion that is positioned at impeller 18 to primary blades 24 vertically from the impeller front, and radially extends to the impeller outer edge from impeller boss.Each primary blades 24 has the leading edge 24A at the front end place that is positioned at impeller 18 and is positioned at the trailing edge 24F of the outer circumference of impeller 18 in radial plate 17 the place ahead close vicinity.

Impeller 18 also comprises intermediate blade 25, and intermediate blade 25 is between each primary blades 24, and they are different from primary blades 24, and intermediate blade 25 is shorter vertically: the leading edge 25A of these blades 25 is with respect to the leading edge 24A withdrawal (promptly backward) of primary blades 24.Different therewith is that the trailing edge 25F of intermediate blade 25 orientates as with axle A with the trailing edge 24F of blade 24 has identical radial distance.

The stereogram of Fig. 3 demonstrates the primary blades 24 of impeller 18 and the rear section of intermediate blade 25 in detail.

The radially cutting plane that intersects at

trailing edge

24F and 25F with the blade 24 of impeller 18 and 25 (promptly; Plane perpendicular to axle A) in; For example in planar I V-IV shown in Figure 2; The direction bending that

blade

24 and 25 edges are opposite with the impeller sense of rotation, wherein the sense of rotation of impeller 18 is represented by arrow R in Fig. 3 and 4.

In this identical radially cutting plane, the part of said

blade

24 and 25 trailing edge is along the changed course of impeller sense of rotation, and its mode is held

fin

26,27 for their form, and is used for through air is radially altered course and the deflection air stream.

Radially in the cutting plane, end

fin

26,27 cooperates with the part of the blade that is positioned at said

end fin

26,27 upper reaches

close vicinity

24,25 at this, with formation more than or equal to 155 ° and strictness obtuse angle T less than 180 °.This angle T is presented among Fig. 4, and Fig. 4 is the sectional view of primary blades 24 in radially cutting plane IV-IV shown in Figure 2.

In the embodiment shown, primary blades 24 all has

end fin

26,27 with intermediate blade 25.In other unshowned embodiments, only primary blades 24 or only intermediate blade 25 have such end fin.

In one embodiment, when end fin 26 is present in 24 last times of primary blades, the extra curvature edge 24E measured lengths (with the curve abscissa) of the said blade 24 in the edge of each end fin 26 is rendered as 15% of the total length that is not more than said outward edge 24E.For example, the length of end fin appear the total length that is at least outward edge 24E 2% and be not more than 10% of this total length.

In one embodiment, when end fin 27 is present in 25 last times of intermediate blade, the extra curvature edge 25E measured lengths (with the curve abscissa) of the said blade 25 in the edge of each end fin 27 is rendered as 15% of the total length that is not more than said outward edge 25E.For example, the length of end fin appear the total length that is at least outward edge 25E 2% and be not more than 10% of this total length.

Claims

1. centrifugal impeller that fluid is passed that is used for compressor, this impeller (18) has: the forward part of running shaft (A), small bore and heavy in section rear section, said impeller (18) has blade (24; 25), each blade have leading edge (24A, 25A) and trailing edge (24F; 25F), the rotation of said impeller (18) makes fluid suck via the front portion of said impeller, and the axial velocity of passing the fluid of said impeller is changed into radial velocity gradually; Said fluid said vane trailing edge (24F, the outer circumference that 25F) is in said impeller (18) is left said impeller (18), said blade (24; 25) make with said vane trailing edge (24F, in the radially cutting plane that 25F) intersects, the said blade edge direction opposite with the sense of rotation of said impeller is crooked; Said impeller (18) is characterised in that

In said radially cutting plane, the rear edge part of said blade (24,25) is along the sense of rotation changed course of said impeller, and its mode forms end fin (26,27) for it, thereby flowing of fluid is deflected owing to radially altering course; (24F, 25F) (24E, 25E) measured lengths, this length are rendered as less than said outward edge (24E, 15% of total length 25E) outward edge of the extend through one said blade in edge (24,25) said end fin (26,27) from said vane trailing edge.

2. centrifugal impeller as claimed in claim 1, wherein, in said radially cutting plane, said end fin (26,27) forms more than or equal to 155 ° and strict obtuse angle (T) less than 180 °, and wherein said blade-section is positioned at the close vicinity at the upper reaches of said end fin.

3. according to claim 1 or claim 2 centrifugal impeller; Wherein, Said impeller has primary blades (24); And have alternatively between said primary blades and be shorter than the intermediate blade (25) of said primary blades in the axial direction, said primary blades (24) and/or said intermediate blade (25) have said end fin (26,27).

4. centrifugal impeller as claimed in claim 3, wherein, said primary blades (24) has said end fin (26).

5. centrifugal impeller as claimed in claim 4; Wherein, Said end fin (26) is from trailing edge (24F) extend through of said primary blades (24) length when measuring along the outward edge (24E) of said primary blades (24), be rendered as during this length greater than the total length of said outward edge (24E) 2% and less than 10% of this total length.

6. like each described centrifugal impeller in the claim 3 to 5, wherein, said intermediate blade (25) has said end fin (27).

7. centrifugal impeller as claimed in claim 6; Wherein, Outward edge (25E) along said intermediate blade (25); Said end fin (27) is from trailing edge (25F) extend through of said intermediate blade (25) length when measuring along the outward edge (25E) of said intermediate blade, this length be rendered as greater than the total length of said outward edge (25E) 2% and less than 10% of this total length.

8. a compressor comprises like each described centrifugal impeller (18) in the claim 1 to 7.

9. a turbo machine comprises compressor as claimed in claim 8.