EP3449185A1

EP3449185A1 - Air intake swirler for a turbomachine injection system comprising an aerodynamic deflector at its inlet

Info

Publication number: EP3449185A1
Application number: EP17725689.8A
Authority: EP
Inventors: Romain Nicolas Lunel; Guillaume Aurélien GODEL; Haris MUSAEFENDIC; Christophe Pieussergues; François Pierre Georges Maurice RIBASSIN
Original assignee: Safran Aircraft Engines SAS
Current assignee: Safran Aircraft Engines SAS
Priority date: 2016-04-28
Filing date: 2017-04-28
Publication date: 2019-03-06
Anticipated expiration: 2037-04-28
Also published as: CN109073224A; FR3050806A1; FR3050806B1; US10883718B2; US20200033007A1; WO2017187104A1; CN109073224B; EP3449185B1

Abstract

An air intake swirler (100, 200) for a turbomachine injection system (70) comprises an upstream wall (102, 202) and a downstream wall (104, 204), both of revolution about an axis (44) of the air intake swirler, and fins (106, 206) distributed about the axis (44) and connecting the upstream wall to the downstream wall so as to delimit, between the upstream wall and the downstream wall, air inlet channels (108, 208) each having an inlet (110, 210) and an outlet (112, 212).The swirler comprises two aerodynamic deflectors (120, 220) that respectively extend the downstream walls (104, 204) radially outward and that have a concavity oriented upstream. The aerodynamic deflectors extend radially facing the respective inlets (110, 210) of the air inlet channels and thus make it possible to limit the loss of pressure of the air supplied to the air inlet channels (108, 208).

Description

AIR INTAKE GUN FOR TURBOMACHINE INJECTION SYSTEM COMPRISING AN AERODYNAMIC DEFLECTOR AT ITS ENTRY

DESCRIPTION TECHNICAL FIELD

The present invention relates to an air intake swirler intended to form part of an air and fuel injection system in a turbomachine, as well as to an injection system for a turbomachine comprising at least one such swirler. air intake, and an aircraft turbomachine comprising such an injection system.

STATE OF THE PRIOR ART

FIG. 1 appended illustrates a turbine engine 10 for an aircraft of a known type, for example a turbojet engine, generally comprising a fan 12 intended for the suction of an air flow dividing downstream of the fan. in a primary flow supplying a heart of the turbomachine and a secondary flow bypassing the heart. The heart of the turbomachine generally comprises a low-pressure compressor 14, a high-pressure compressor 16, a combustion chamber 18, a high-pressure turbine 20 and a low-pressure turbine 22. The turbine engine is streamlined by a nacelle 24 surrounding the flow space 26 of the secondary flow. The rotors of the turbomachine are rotatably mounted about a longitudinal axis 28 of the turbomachine.

FIG. 2 represents the combustion chamber 18 of the turbomachine of FIG. 1. In a conventional manner, this combustion chamber, which is of annular type, comprises two coaxial annular walls, respectively radially inner 32 and radially outer 34, which extend from upstream to downstream, in the flow direction 36 of the primary flow of gas in the turbomachine, around the axis of the combustion chamber which merges with the axis 28 of the turbomachine. These inner and outer annular walls 32 are interconnected at their upstream end by an annular chamber bottom wall 40 which extends substantially radially about the axis 28. This annular bottom wall of the chamber 40 is equipped with injection systems 42 distributed around the axis 28 to allow, each, injection of a premix of air and fuel centered along a respective injection axis 44. Throughout the present description, the axial and radial directions are defined by reference to the injection axis 44. In addition, a transverse plane is a plane orthogonal to the injection axis 44.

The combustion chamber generally comprises an annular protective fairing 45 extending opposite an upstream face of the chamber bottom wall 40 and having injector and air inlet orifices.

In operation, a portion 46 of an air flow 48 coming from a diffuser 49 and coming from the compressor 16 feeds the injection systems 42 while another part 50 of this air flow bypasses the combustion chamber flowing downstream along the coaxial walls 32 and 34 of this chamber and allows in particular the supply of air inlet openings provided within these walls 32 and 34.

As shown in FIG. 3, each injection system 42 generally comprises a bushing 52, sometimes referred to as a "sliding bushing", in which a fuel injection nose 54 forming the end of an injector arm 55 is mounted, and one or more air intake swirlers 56, 58, and finally a bowl 60, sometimes referred to as "mixing bowl" or "pre-vaporization bowl", which takes essentially the form of a wall annular having a frustoconical part flared downstream. These elements are centered with respect to the injection axis 44.

The air intake swirlers 56, 58 (also known as "swirlers") are separated from each other by an annular wall which extends radially inwardly to form an airfoil. internal deflection annular wall 62, also called "venturi", having an internal profile of convergent-divergent shape.

The injection systems 42 have an essential role in the operation of the combustion chamber. Their effectiveness depends in particular on the quality of their air supply that comes directly from the diffuser. In this respect, the air intake swirlers 56, 58 contribute to the mixing of air and fuel. Each swirler 56, 58 thus comprises an annular row of fins inclined so as to rotate the air flow 64 and thus improve the atomization of the jet of fuel from the fuel injection nose 54. In particular, a part of this fuel flows in liquid form on the inner surface of the venturi 62 and is sheared by the swirling air at the downstream end of the venturi 62.

STATEMENT OF THE INVENTION

The purpose of the invention is to improve the performance of the injection systems of the turbomachines.

To this end, it proposes an air intake swirler for a turbomachine injection system, comprising an upstream wall and a downstream wall both of revolution about an axis of the air intake swirler, and fins distributed around the axis and connecting the upstream wall to the downstream wall so as to delimit between the upstream and downstream walls of the air inlet channels each having an inlet arranged on a radially outer side and an arranged outlet d a radially internal side.

According to the invention, the air intake swirler further comprises an aerodynamic deflector which extends the downstream wall radially outwards to a free end of the aerodynamic deflector, and which has a concavity facing upstream of so that the aerodynamic deflector extends radially facing the respective inputs of the air inlet channels.

Generally speaking, the aerodynamic deflector makes it possible to channel the flow of air intended to enter the air intake ducts and thus to limit as much as possible the pressure losses of this air flow.

This results in an improvement in the overall performance of a turbomachine combustion chamber equipped with an injection system comprising such an air intake swirler, in particular in terms of overall thermodynamic cycle. In a first preferred embodiment of the invention, the aerodynamic deflector extends continuously 360 degrees about the axis, from the downstream wall to the free end of the aerodynamic deflector.

In a second preferred embodiment of the invention, the aerodynamic deflector comprises recesses formed in the free end of the aerodynamic deflector so as to delimit between them teeth respectively arranged opposite the respective inlets of the air inlet channels. .

Preferably, the upstream and downstream walls extend substantially orthogonal to the axis.

Furthermore, the aerodynamic deflector is preferably shaped so that at each point of the free end of the aerodynamic deflector, a circumferential plane tangential to a radially inner edge of the free end is substantially parallel to the axis of the spin air intake.

The invention also relates to an injection system for injecting a mixture of air and fuel into a turbomachine combustion chamber, comprising a sleeve for centering an injector, a bowl, and at least a first auger. air intake of the type described above arranged axially between the sleeve and the bowl.

Preferably, the injection system further comprises a second air intake auger also of the type described above, arranged axially between the first air intake auger and the bowl.

In this case, the downstream wall of the first air intake swirler is preferably the upstream wall of the second air intake swirler.

In addition, the injection system advantageously comprises an annular internal deflection wall having an internal profile of convergent-divergent shape, which extends the downstream wall of the first air intake auger towards the inside of the injection system. .

Preferably, the respective free ends of the respective aerodynamic baffles of the first and second air intake spindles extend substantially in the same transverse plane. In this case, the upstream wall of the first air intake swirler advantageously extends in the same transverse plane.

As a variant, the respective free ends of the respective aerodynamic baffles of the first and second air intake jibs can be offset relative to each other in the direction of the axis of the air intake swirler. .

In preferred embodiments of the invention, each of the respective aerodynamic baffles of the first and second air intake booms is of revolution about the axis of the air intake swirler.

In other preferred embodiments of the invention, at least one of the respective aerodynamic baffles of the first and second air intake booms is shaped so that the radial extent of the inlet section of the air of the corresponding air intake swirl varies around the axis of the air intake swirl.

The invention also relates to an aircraft turbomachine, comprising a combustion chamber and at least one injection system of the type described above for supplying the combustion chamber with a mixture of air and fuel.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood, and other details, advantages and characteristics thereof will appear on reading the following description given by way of non-limiting example and with reference to the accompanying drawings in which:

FIG. 1, already described, is a schematic view in axial section of a turbomachine of a known type;

FIG. 2, already described, is a schematic half-view in axial section of a combustion chamber of the turbomachine of FIG. 1;

FIG. 3, already described, is a diagrammatic view in axial section of an injection system of the combustion chamber of FIG. 2; FIG. 4 is a schematic half-view in axial section of an injection system according to a first preferred embodiment of the invention;

FIG. 5 is a partial schematic view in perspective and in axial section of the injection system of FIG. 4;

FIGS. 6 and 7 are diagrammatic views, respectively in perspective and from the front, of an injection system according to a second preferred embodiment of the invention;

- Figures 8 to 11 are schematic perspective views of injection systems according to other preferred embodiments of the invention.

In all of these figures, identical references may designate identical or similar elements.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 4 and 5 illustrate an injection system 70 similar to the injection system 42 of FIG. 2 described above but comprising two air intake swirlers 100, 200 which are both in accordance with a first embodiment of FIG. preferred embodiment of the invention. The injection system 70 is intended to equip an aircraft turbomachine of the same type as the turbomachine of FIG. 1 described above, or any other type of turbomachine.

The injection system 70 thus comprises a bushing 52 intended to receive a fuel injection nose, the air intake swirlers 100, 200, and a bowl 60. The air intake swirlers 100, 200 are intended for injecting a swirling air flow into two internal annular spaces of the injection system separated from each other by an annular internal deflection wall 62 having an internal profile of convergent-divergent shape, also called "venturi", as explained above in relation to the injection system 42 of known type.

The first air intake swirler 100, also called "internal swirler", has an upstream wall 102 and a downstream wall 104 which are both of revolution about an axis of the swirl which merges with the axis. injection 44 of the injection system. The first air intake swirler 100 further comprises fins 106 distributed around the axis 44 and connecting the upstream wall 102 to the downstream wall 104 so as to delimit between the upstream and downstream walls of the air inlet channels 108. Each air inlet channel 108 has an inlet 110 arranged on a radially outer side and an outlet 112 arranged on a radially inner side. More specifically, each inlet 110 is delimited between respective radially outer ends of the two consecutive fins 106 which delimit the corresponding air inlet channel 108. Similarly, each outlet 112 is delimited between respective radially inner ends of the two consecutive fins 106 which delimit the corresponding air inlet channel 108.

According to a feature of the invention, the first air intake swirler

100 further comprises an aerodynamic deflector 120 which extends the downstream wall 104 radially outwardly to a free end 122 of the aerodynamic deflector 120. The latter has a concavity facing upstream. The aerodynamic deflector 120 thus extends radially opposite the respective inlets 110 of the air inlet channels 108. The free end 122 of the aerodynamic deflector 120 is thus oriented generally towards the upstream and delimits a section of air intake of the first air intake swirler 100.

In general, the aerodynamic deflector 120 thus makes it possible to channel the flow of air F1 entering the air intake channels 108 and thus to limit the pressure losses of this air flow as much as possible.

In the first preferred embodiment of the invention illustrated in Figures 4 and 5, the aerodynamic deflector 120 extends continuously 360 degrees about the axis 44, from the downstream wall 104 to the free end 122 of the aerodynamic deflector 120.

In the illustrated example, the upstream and downstream walls 102 102 of the first air intake auger 100 extend orthogonally to the axis 44. The auger is therefore of the radial type and thus has an optimal compactness in the direction axial.

As a variant, the upstream and downstream walls 102 may be inclined with respect to the axis 44 without departing from the scope of the invention. In addition, in the illustrated example, the aerodynamic deflector 120 has a curved shape from the downstream wall 104 and up to the free end 122.

The aerodynamic deflector 120 may advantageously be manufactured by means of an additive manufacturing process, for example of the selective laser melting (SLM) type.

Alternatively, the aerodynamic deflector 120 may have one or more curved axial sections and one or more cylindrical or frustoconical axial sections arranged axially end-to-end, without departing from the scope of the invention.

As a further variant, the aerodynamic baffle 120 may consist of a succession of axial sections of frustoconical shape, having respective black and white rims smaller than the axial section in question is remote from the downstream wall 104. Otherwise said aerodynamic deflector 120 may have a segmented curvature instead of a continuous curvature, without departing from the scope of the invention.

Furthermore, in the illustrated example, the aerodynamic deflector 120 is shaped so that at each point of its free end 122, a circumferential plane PI tangential to a radially inner edge 124 of the free end 122 is parallel to the axis 44 of the first air intake swirler 100.

In addition, the aerodynamic deflector 120 is of revolution about the axis 44. The aerodynamic deflector 120 thus delimits an air inlet section of the first air intake auger 100, of constant radial extent SI around of axis 44.

In preferred embodiments of the invention, the air inlet section of the first air intake swirler 100 is greater than or equal to three times the sum of respective passage sections of the air intake channels. air 108 of the first air intake swirler 100.

Alternatively, the aerodynamic deflector 120 may have an irregular shape around the axis 44 so as to adapt the radial extent SI of the air inlet section to the pressure irregularities of the air flow 46 from the diffuser 49 turbomachine, as will become clearer in what follows. The second air intake swirler 200, which is arranged axially between the first air intake swirler 100 and the bowl 60, has a configuration similar to that of the first air intake swirler 100.

In particular, the second air intake swirler 200, also called "external swirler", has an upstream wall 202, which is the downstream wall 104 of the first air intake swirler 100, and a downstream wall 204. The two walls 202, 204 are of revolution about the axis of the swirler 200 which merges with the injection axis 44 of the injection system. The second air intake swirler 200 further comprises fins 206 distributed around the axis 44 and connecting the upstream wall 202 to the downstream wall 204 so as to delimit between the upstream and downstream walls of the inlet channels. 208. Each air inlet channel 208 has an inlet 210 arranged on a radially outer side and an outlet 212 arranged on a radially inner side. More specifically, each inlet 210 is delimited between respective radially outer ends of the two consecutive fins 206 which delimit the corresponding air inlet channel 208. Similarly, each outlet 212 is delimited between respective radially inner ends of the two consecutive fins 206 which delimit the corresponding air inlet channel 208.

In addition, the second air intake swirler 200 includes an aerodynamic deflector 220 which extends the downstream wall 204 radially outwardly to a free end 222 of the aerodynamic deflector 220 oriented generally towards the upstream and delimiting an air intake section of the second air intake swirler 200.

The aerodynamic deflector 220 has characteristics similar to those of the aerodynamic deflector 120 of the first air intake swirler 100 described above, and thus makes it possible to channel the air flow F 2 entering the inlet channels of air 208.

In particular, a circumferential plane P2 tangential to a radially inner edge 224 of the free end 222 is parallel to the axis 44 of the second air intake swirler 200 (FIG. 4). In the example illustrated, the respective free ends 122, 222 of the respective aerodynamic deflectors 120, 220 of the first and second air intake auger 100, 200 extend substantially in the same transverse plane P3, in which also the upstream wall 102 of the first air intake auger 100. Thus, the air inlet sections delimited respectively by the aerodynamic deflectors 120 and 220 are defined substantially in the transverse plane P3.

Furthermore, the annular internal deflection wall 62 extends in the extension of the downstream wall 104 of the first air intake auger 100 towards the inside of the injection system 70.

Figures 6 and 7 illustrate an injection system 70A substantially similar to the injection system 70 described above, but wherein the first and second air intake auger 100A, 200A differ from the auger 100, 200 described herein. above, because each of their respective aerodynamic baffles 120A, 220A has recesses 126A, 226A formed in its free end 122A, 222A. These recesses 126A, 226A delimit between them teeth 128A, 228A respectively arranged opposite the respective inlets 110, 210 of the air inlet channels 108, 208.

The teeth 128A of the aerodynamic deflector 120A of the first air intake swirler 100A are advantageously angularly offset relative to the teeth 228A of the aerodynamic deflector 220A of the second air intake swirler 200A, so that each tooth 128A is arranged axially facing a recess 226A corresponding.

The recesses 126A of the aerodynamic deflector 120A of the first air intake swirler 100A thus allow to pass an excess of air towards the second air intake swirler 200A.

Alternatively, an injection system according to the invention may comprise a single air intake swirler, or a first air intake swirler according to the second embodiment described above and a second swirl of air. air intake according to the first embodiment described above, or vice versa.

FIG. 8 illustrates an injection system 70B substantially similar to the injection system 70 described above, but in which the aerodynamic deflector 220B of the second air intake swirler 200B is shaped such that the radial extent S2 of the air inlet section of said air intake swirler 200B varies about the axis 44.

In the example illustrated in FIG. 8, the aerodynamic deflector 220B is in particular shaped so that its free end 222B is circular in shape and eccentric with respect to the axis 44. The free end 222B is, for example, eccentric from the axis 44 in a direction radially outwardly with respect to the axis 28 of the combustion chamber (visible in Figure 2).

The radial extent S2 preferably takes a minimum value S2min equal to half of a nominal value corresponding to the radial extent that would have an equivalent section but constant radial extent (as in Figures 4 and 5). In addition, the radial extent S2 preferably takes a maximum value S2max equal to three times the nominal value.

Alternatively, the variability of the radial extent S2 of the air inlet section can be obtained by a non-axisymmetric shape of the aerodynamic deflector 220B, for example an off-center oval shape.

Alternatively or in a complementary manner, the aerodynamic deflector of the first air intake swirler may adopt a configuration such that the radial extent SI of the air intake section of the first air intake swirler varies around axis 44.

In general, the variability of the radial extent of the air intake section of at least one of the intake air auger makes it possible to optimize the homogeneity of the air supply of this twist with respect to various design parameters of the turbomachine, including in particular the possible heterogeneity of the flow at the output of the compressor 16, the wake induced by the injector arm 55 in the air flow supplying the fuel system. injection 70B, and the influence of the annular protective fairing 45 on the aforementioned air flow.

Other variants make it possible to optimize the supply of air to the intake air gages according to such parameters, as shown in FIGS. 9 to 11. FIGS. 9 and 10 respectively illustrate injection systems 70C and 70D that are generally similar to the injection system 70 described above, but in which the respective free ends of the respective aerodynamic deflectors of the first and second air intake gears are offset relative to each other in the direction of the axis 44.

Thus, in the embodiment of FIG. 9, the aerodynamic deflector 120C of the first air intake swirler 100C extends upstream beyond the free end 222 of the aerodynamic deflector 220 of the second air intake swirler 200.

Conversely, in the embodiment of FIG. 10, the aerodynamic deflector 220D of the second air intake swirler 200D extends upstream beyond the free end 122 of the aerodynamic deflector 120 of the first air intake swirler 100.

Finally, FIG. 11 illustrates an injection system 70E similar to that of FIG. 10, except that the aerodynamic deflector 220E of the second air intake swirler 200E has an oval or oblong free end 222E, extending for example from an annular portion of circular section 223E of the deflector.

In the illustrated example, the major axis 230E of the free end 222E is oriented in a circumferential direction defined with respect to the axis 28 of the combustion chamber (visible in Figure 2).

The shape of the free end 222E makes it possible to obtain a variability of the radial extent of the air inlet section of the second air intake swirler 200E about the axis 44, in a similar way to what has been described with reference to FIG.

Claims

An injection system (70; 70A; 70B; 70C; 70D; 70E) for injecting a mixture of air and fuel into a turbomachine combustion chamber, comprising a bushing (52) for centering an injector , a bowl (60), a first air intake swirler (100; 100A; 100C) arranged axially between the bushing (52) and the bowl (60), and a second air intake swirler (200); 200A; 200B; 200D; 200E) arranged axially between the first air intake swirler (100; 100A; 100C) and the bowl (60), each of the air intake swirlers comprising an upstream wall (102); 202) and a downstream wall (104, 204) both of revolution about an axis (44) of the air intake swirler and vanes (106, 206) distributed about the axis (44). ) and connecting the upstream wall to the downstream wall so as to delimit between the upstream and downstream walls of the air inlet channels (108, 208) each having an inlet (110, 210) arranged on a radially outer side and output (112, 212) arranged on a radially inner side, wherein the downstream wall (104) of the first air intake swirler (100; 100A; 100C) is the upstream wall (202) of the second air intake auger (200; 200A; 200B; 200D; 200E), characterized in that each of the air intake auger further includes an aerodynamic deflector (120, 220; 120A, 220A; 120, 220B; 120C, 220; 120, 220D; 120, 220E) respectively extending the downstream wall (104, 204) of the corresponding air intake swirl radially towards the and ends with a free end (122, 222; 122A, 222A; 122, 222B; 122, 222E), each respective aerodynamic deflector having a concavity facing upstream so that the aerodynamic deflector extends radially. respective inlets (110, 210) of the air inlet channels of the corresponding air intake swirler.

Injection system according to claim 1, wherein the aerodynamic deflector (120, 220; 120, 220B; 120C, 220; 120, 220D; 120, 220E) of at least one of the first and second air intake (100, 200; 100, 200B; 100C, 200; 100, 200D; 100, 200E) extends continuously 360 degrees about the axis (44) from the downstream wall (104, 204) to the free end (122, 222; 122, 222B; 122, 222E) of the aerodynamic deflector.

Injection system according to claim 1, wherein the aerodynamic deflector (120A, 220A) of at least one of the first and second air intake spins (100A, 200A) has recesses (126A, 226A) formed in the free end (122A, 222A) of the aerodynamic deflector so as to delimit between them teeth (128A, 228A) respectively arranged opposite the respective inlets (110, 210) of the air intake channels of the corresponding air intake swirler (100A, 200A).

4. Injection system according to any one of claims 1 to

3, wherein the upstream (102, 202) and downstream (104, 204) walls of each of the first and second air intake swirlers (100, 200; 100A, 200A; 100, 200B; 100C, 200; 100 , 200D; 100, 200E) extend substantially orthogonal to the axis (44).

Injection system according to any one of claims 1 to

4, wherein the aerodynamic baffle (120, 220; 120A, 220A, 120, 220B; 120C, 220; 120, 220D; 120, 220E) of each of the first and second air intake spins (100, 200; 100A, 200A, 100, 200B; 100C, 200; 100, 200D; 100, 200E) is shaped so that at each point of the free end (122, 222) of the aerodynamic deflector, a circumferential plane (P1, P2 ) tangent to a radially inner edge (124, 224) of the free end is substantially parallel to the axis (44).

Injection system according to any one of claims 1 to

5, further comprising an annular inner deflection wall (62) having an internal convergent-divergent profile, which extends the downstream wall (104) of the first air intake auger into the interior of the air intake system. injection.

An injection system according to any one of claims 1 to 6, wherein the respective free ends (122, 222; 122A, 222A, 122, 222B) of the respective air deflectors (120, 220; 120A, 220A; 120 220B) of the first and second air intake spins (100, 200; 100A, 200A; 100, 200B) extend substantially in the same transverse plane (P3).

8. Injection system according to claim 7, wherein the upstream wall (102) of the first air intake auger (100; 100A) extends in the same transverse plane (P3).

Injection system according to any one of claims 1 to 6, wherein the respective free ends (122, 222) of the respective aerodynamic deflectors (120C, 220; 120, 220D) of the first and second intake air (100C, 200; 100, 200D) are offset relative to each other in the direction of the axis (44).

An injection system according to any one of claims 1 to 9, wherein each of the respective aerodynamic baffles (120, 220; 120C, 220; 120, 220D) of the first and second air intake gears (100 , 200; 100C, 200; 100, 200D) is revolution about the axis (44).

An injection system according to any one of claims 1 to 9, wherein at least one of the respective aerodynamic baffles (220B, 220E) of the first and second air intake gears is shaped such that the the radial extent (S2) of the air inlet section of the corresponding air intake swirler (200B; 200E) varies around the axis (44).

12. Turbine engine for aircraft, comprising a combustion chamber and at least one injection system (70, 70A) according to any one of claims 1 to 11 for supplying the combustion chamber with a mixture of air and fuel.