Annular oil catch can for a turbomachine, and exhaust module including such a catch can

Abstract

The invention relates to an annular oil recovery housing (70) for a turbomachine, extending around an axis (A) comprising: - a radial annular wall (80); - a cylindrical wall (90); - angled conduits (100) distributed around the axis (A) and the cylindrical wall (90) and connected to the radial (80) and cylindrical (90) walls. According to the invention, the housing further comprises: - at least one gutter (110) connected to a portion of said conduits (100) to collect oil accumulated in these conduits (100), and - at least one discharge port (120) which is in fluidic communication with the gutter (110) and capable of discharging the collected oil to the outside of the housing (70). Figure 3

Description

Title of the invention: ANNULAR OIL RECOVERY COVER FOR A TURBOMACHINE, AND EXHAUST MODULE INCLUDING SUCH A COVER Technical field of the invention

[0001] The present invention relates to an annular oil recovery housing for a turbomachine, particularly an aircraft turbomachine, and an exhaust module for such a turbomachine, comprising the annular oil recovery housing. Technical background

[0002] An aircraft turbomachine includes a gas generator which conventionally comprises, from upstream to downstream, with reference to the gas flow in the turbomachine, at least one compressor, an annular combustion chamber, and at least one turbine. In the case of a twin-spool turbojet engine, with low-pressure and high-pressure cylinders respectively, the gas generator comprises successively a low-pressure compressor, a high-pressure compressor, the combustion chamber, a high-pressure turbine, and a low-pressure turbine. The rotor of the low-pressure compressor is driven by the rotor of the low-pressure turbine, and the rotor of the high-pressure compressor is driven by the rotor of the high-pressure turbine.

[0003] The gas generator also defines an annular flow channel for a gas stream that passes through the compressors, the combustion chamber, and the turbines. This channel is called the primary channel, and the gas stream flowing through it is called the primary stream.

[0004] In the present application, the term "casing" means a structural element mounted in the turbomachine to perform one or more functions, and in particular an interface or mechanical link between two stator parts.

[0005] At the downstream end of the primary stream, for example, the gas generator includes an exhaust module which includes an exhaust housing which has two coaxial annular walls which define the stream between them and which are connected to each other by radial arms.

[0006] In this environment or elsewhere in the turbomachine, a housing can be used to ensure the flow of a gas stream. This is the case, for example, when a gas stream must be directed to a sealing joint in order to increase its surrounding pressure.

[0007] The gas stream may be laden with oil, and oil is likely to flow onto the crankcase and accumulate within it during operation. This poses a risk to the turbomachine's operation and causes premature wear of the crankcase (particularly due to oil coking). Therefore, there is a need to manage this oil, and in particular to remove it so that it can be recycled.

[0008] The present invention proposes a simple, effective and economical solution to the need mentioned above. Summary of the invention

[0009] The invention relates to an annular oil recovery housing for a turbomachine, in particular for aircraft, this housing extending around an axis and comprising:

[0010] - a radial annular wall extending perpendicularly to the axis and comprising an annular row of first axially oriented orifices,

[0011] - a cylindrical wall extending around the axis and comprising an annular row of second radially oriented orifices, the cylindrical wall being connected to an internal periphery of the radial wall,

[0012] - angled conduits distributed around the axis and the cylindrical wall and connected to radial and cylindrical walls, each of these conduits connecting one of the first orifices to one of the second orifices.

[0013] According to the invention, the housing further comprises:

[0014] - at least one circular arc gutter extending around the axis and connected to a portion of said conduits to be suitable for collecting oil accumulated in these conduits, and

[0015] - at least one drainage port which is in fluidic communication with the gutter and capable of expelling the collected oil to the outside of the crankcase.

[0016] The housing according to the invention incorporates several functions. First, it provides the interface between one or more parts of the turbomachine. The housing is also capable of allowing the flow of a gas stream through its conduits, and of collecting and draining any oil that may be present in this gas stream. To this end, the housing includes, in particular, a gutter that allows, on the one hand, the collection of oil present in the recovery housing, specifically oil present in at least some of the conduits, and on the other hand, the guidance of this oil towards the discharge port so as to drain the collected oil to the outside of the housing, notably for recycling. The invention thus makes it possible to integrate several functions into a housing, including the passage of a gas stream and the collection and drainage of oil contained in this gas stream.

[0017] The housing according to the invention may comprise one or more of the following features, taken individually or in combination with each other: - the casing is made from a single piece. - the gutter has an angular extent around the axis of between 150 and 200°, and preferably of the order of 180°. - said at least one port is located in the middle of the gutter, that is to say halfway between the circumferential ends of the gutter. - the gutter has a first circumferential end located at 3 o'clock, and a second circumferential end located at 9 o'clock, and the gutter extends over a lower half of the casing, 3 o'clock and 9 o'clock being angular positions around the axis by reference to the dial of a clock. - the port is located at 6 a.m. - the casing further includes a tub formed in the cylindrical wall and in fluidic communication with said at least one port, or even also with the gutter, the tub being suitable for collecting oil that may flow down the cylindrical wall. - at least one of the first openings leads directly into the bathtub. - at least two or three adjacent first openings lead directly into the bathtub. - the number of conduits is between 10 and 30, and preferably between 15 and 25. - Each of the conduits has a parallelepiped shape in cross-section. - It includes at one axial end an annular fixing flange, which extends perpendicularly to the axis and which includes axial holes suitable for receiving fixing elements. - said radial wall includes axial through holes suitable for receiving fixing elements. - each of the holes in the radial wall is intercalated between two first orifices, and each of the first orifices is intercalated between two holes in the radial wall.

[0018] The invention also relates to an exhaust module for a turbomachine, particularly an aircraft turbomachine, comprising an oil recovery housing as described above. The oil recovery housing is surrounded by an exhaust housing having two coaxial annular walls that define a flow path for an exhaust gas stream and are connected to each other by radial arms. The oil recovery housing is axially interposed between at least one roller bearing, the outer ring of which is connected to the exhaust housing. and to the oil recovery sump, and an electric machine whose stator is connected to the oil recovery sump. Brief description of the figures

[0019] Other features and advantages of the invention will become apparent upon reading the detailed description that follows, for an understanding of which reference should be made to the accompanying drawings in which:

[0020] [Fig-1] [Fig.1] is a schematic axial cross-sectional view of a turbomachine aircraft,

[0021] [Fig.2] [Fig.2] is a schematic axial cross-sectional view of a module exhaust system according to the invention,

[0022] [Fig.3] [Fig.3] is a schematic perspective view of a housing according to the invention,

[0023] [Fig.4] [Fig.4] is a front view of the casing of [Fig.3] viewed from downstream towards upstream,

[0024] [Fig.5] [Fig.5] is a partial schematic axial cross-sectional view of a housing according to the invention disposed between a bearing support and an electrical machine,

[0025] [Fig.6] [Fig.6] is a schematic radial cross-sectional view of one quarter of the housing of [Fig.3], and

[0026] [Fig.7] [Fig.7] is a schematic view of the housing of [Fig.3] according to another perspective. Detailed description of the invention

[0027] Fig. 1 schematically represents a turbomachine 10 for an aircraft, and in particular a turbomachine with an unfaired propeller extending around a longitudinal axis A.

[0028] The turbomachine 10 comprises a gas generator 12 which conventionally includes, from upstream to downstream, with reference to the flow of gases in the turbomachine 10, at least one compressor 14, 16, an annular combustion chamber 18 and at least one turbine 20, 22. In the case of a twin-spool turbojet, respectively low pressure and high pressure, the gas generator 12 includes successively a low pressure compressor 14, a high pressure compressor 16, the combustion chamber 18, a high pressure turbine 20 and a low pressure turbine 22.

[0029] The gas generator 12 defines an annular flow channel V1 for a gas stream that passes through the compressors 14, 16, the combustion chamber 18, and the turbines 20, 22. This channel VI is called the primary flow channel, and the gas stream Fl flowing through it is called the primary stream FL

[0030] The rotor of the high-pressure compressor 16 is connected to the rotor of the high-pressure turbine 20 by a high-pressure shaft 24. The rotor of the low-pressure compressor 16 and connected to the rotor of the low pressure turbine 22 by a low pressure shaft 26 which passes through the high pressure shaft 24 and which drives in rotation, directly or via a reduction gear, a blower propeller SI located generally upstream of the gas generator 12.

[0031] The fan propeller SI can be shrouded or unshrouded. In the example shown, it is unshrouded. The fan propeller SI generates an airflow F, part of which enters the gas generator 12 to form the primary flow Fl, and part flows around the gas generator 12 to form a secondary flow F2 in a secondary channel V2. In practice, this separation of the airflow F is achieved by means of an annular separation nozzle 32 located downstream of the fan propeller SI, which is capable of separating the airflow F passing through the fan propeller SI into two flows, internal and external respectively, capable of forming the primary flow Fl and secondary flow F2 and flowing respectively into channels VI and V2.

[0032] The turbomachine 10 also includes a rectifier 34 configured to rectify the secondary flow F2. The rectifier 34 is formed by variable-pitch blades 35, which are also unshod. The rectifier 34 is located downstream of the fan SI, and more specifically downstream of the first separation nozzle 32, in the secondary flow V2.

[0033] The turbomachine 10 also includes an intermediate casing 27 located between the compressors 14 and 16 and an exhaust casing 28 (of the TRF type, an acronym for Turbine Rear Frame, which designates the last casing of the gas generator). These casings 27, 28 form at least part of the structure of the turbomachine 10: in particular, they support bearings that guide the rotating shafts and are connected to the turbomachine 10's suspensions.

[0034] The exhaust casing 28 is located at the downstream end of the flow path VI and is more clearly visible in [Fig. 2]. The exhaust casing 28 comprises an inner wall 28a and an outer wall 28b. The inner wall 28a and the outer wall 28b are coaxial. They define a portion of the primary flow path VI for the primary flow Fl and the exhaust gases. The inner wall 28a and the outer wall 28b are connected by radial arms 35 traversing the primary flow path VL

[0035] The exhaust housing 28 is part of an exhaust module 150. In the example shown, the exhaust module 150 further includes at least one bearing 50 with a low-pressure shaft guide bearing 26, and an electric machine 160.

[0036] The bearing 50 comprises an inner ring 52 integral with the low-pressure shaft 26 and an outer ring 51 connected, in particular rigidly, to the exhaust housing 28, especially via a bearing support 55 or the like. The outer ring 51 is connected, for example rigidly, to the housing 70.

[0037] In a known manner, the bearing 50 is housed in an annular enclosure 60 which is supplied with oil and in which an oil mist is present. To prevent oil leakage outside the enclosure 60, it is known to provide seals 54 at the ends of the enclosure 60. These seals 54 are, for example, labyrinth seals or JRS (acronym for Segmented Rotary Seal) and must be pressurized so that pressurized gas enters from the outside to the inside of the enclosure 60, through these seals 54, and thus prevents oil from escaping the enclosure 60 by passing from the inside to the outside of the enclosure through these seals 54.

[0038] The electric machine 160 includes in particular a stator 170 and a rotor 180. In the example shown, it has a general annular shape and is centered on the axis A. The stator 170 extends around the rotor 180 and is integral with the exhaust housing 28.

[0039] According to the invention, the exhaust module 150 further comprises an additional housing 70 which is axially interposed between the bearing 50 and the electric machine 160 and forms an interface between the bearing 50 and the electric machine 160 and in particular between the support 55 of the bearing 50 and the stator 170 of the electric machine 160. The housing 70 therefore has, in particular, the function of providing the mechanical link between the bearing 50 and the electric machine 160.

[0040] This casing 70 is an oil recovery casing 70, a preferred embodiment of which is shown in figures 3 to 7.

[0041] The housing 70 has a generally annular shape and extends around axis A. The housing 70 is, for example, formed in one piece, particularly by casting. The housing 70 is located, in particular, in a zone of a hub of the exhaust housing 28. The inner wall 28a (visible [Fig. 2]) of the housing 28 extends around at least a portion of the oil recovery housing 70. The housing 70 is, in particular, surrounded by the exhaust housing 28.

[0042] The housing 70 is used in particular to ensure the flow of a gas stream (especially air) which must be conveyed to the sealing joints 54 in order to increase their surrounding pressure. The gas stream may be laden with oil, and oil is thus likely to flow onto the housing 70 and accumulate in the housing 70 during operation.

[0043] In other words, the casing 70 allows a flow of oiled gas from the area of ​​the electrical machine 160 to the enclosure 60 to pressurize the latter in a direction T (visible on the [Fig.5]).

[0044] The recovery casing 70 according to the invention allows this oil to be managed and in particular to be evacuated in order in particular to be able to recycle it as explained in particular in the rest of the description.

[0045] The housing 70 includes in particular a radial annular wall 80 extending perpendicularly to the axis A and comprising an annular row of first orifices 81 axially oriented. The number of first orifices 81 is between 10 and 30, and preferably between 15 and 25, in particular 20. Each of the first orifices 81 has, for example, in cross-section a parallelepiped shape.

[0046] The housing 70 comprises, in particular, a cylindrical wall 90 extending around axis A and having an annular row of radially oriented secondary orifices 91. The cylindrical wall 90 is connected to an inner periphery 82 of the radial wall 80. The cylindrical wall 90 and the radial wall 80 are, in particular, perpendicular to each other. The number of secondary orifices 91 is between 10 and 30, and preferably between 15 and 25, in particular 20. Each of the secondary orifices 91 has, for example, a parallelepiped shape in cross-section.

[0047] The housing 70 further comprises, in particular, bent conduits 100 distributed around the axis A and the cylindrical wall 90 and connected to the radial wall 80 and cylindrical wall 90. The bent conduits 100 connect, in particular, a downstream face 83 of the radial wall 80 to an external face 93 of the cylindrical wall 90. The bent conduits 100 form, in particular, an angle of approximately 90°. Each of these conduits 100 connects one of the first ports 81 to one of the second ports 91. The number of conduits is between 10 and 30, and preferably between 15 and 25, in particular 20. Each of the conduits 100 has, for example, a parallelepiped shape in cross-section.

[0048] According to the invention, the housing 70 also includes at least one circular gutter 110 extending around axis A. The gutter 110 is specifically connected to a portion of the conduits 100 to collect oil accumulated in these conduits 100, for example, in the conduits 100 located on the lower half of the housing 70, and in particular in eleven conduits 100 in the example shown. In this way, none of these conduits 100 are affected by an oil retention problem.

[0049] As can be seen in particular in [Fig.4], the gutter 110 has in particular an angular extent around the axis of between 150 and 200°, and preferably of the order of 180°. The gutter 110 has for example a first circumferential end 110a located at 3 o'clock, and in particular a second circumferential end 110b located at 9 o'clock.

[0050] 3h and 9h are angular positions around axis A with reference to the dial of a clock when looking at the casing 70 from the upstream side and towards the downstream side.

[0051] The gutter 110 extends in particular over a lower half of the housing 70. The gutter 110 extends, for example, over an external face of the conduits 100. The gutter 110 extends in particular over a downstream face of the radial wall 80. The gutter 110 does not radially extend beyond the radial wall 80.

[0052] The housing 70 includes, for example, a drain port 120 which is in fluidic communication with the gutter 110 and capable of draining the oil collected by the gutter 110 to the outside of the housing 70. The port(s) 120 (here port 120) is located in particular in the middle of the gutter 110, that is to say midway between the circumferential ends 110a, 110b of the gutter 110. The port 120 is located in particular at 6 o'clock.

[0053] The path of the oil recovered by the casing 70 is illustrated in particular by arrows T in Figures 5 and 6.

[0054] When the oil passes through conduits 100 not connected to the gutter 110 (as illustrated for example by the path T on [Fig.5]), the oil enters the crankcase 70 through the second orifices 91 and then goes to the enclosure 60 via the conduits 100 and the first orifices 81.

[0055] Furthermore, when the oil passes through conduits 100 connected to the gutter 110 (as illustrated, for example, by the paths T in [Fig. 6]), the oil enters the crankcase 70 through the second orifices 91 and then flows towards the enclosure 60 via the conduits 100 and the first orifices 81, as well as via the conduits 100 and the gutter 110. Indeed, the oil enters the gutter 110 partly by gravity through openings 111 connecting the gutter 110 to the conduits 100. The openings 111 are located, in particular, on the side of the conduits 100 closest to the discharge port 120. The openings 111 are therefore positioned, in particular, at the lowest point of each conduit 100 so as to allow the oil to flow, especially by gravity, into the gutter 110. The oil continues its journey to port 120 through which it is evacuated from crankcase 70, notably to be recycled.

[0056] The air pressurization required in the ducts 100 remains unaffected, the evacuation flow rate being calibrated by the diameter of the port 120 for example.

[0057] As can be seen in particular on [Fig.7], the housing 70 may further include a tub 130 formed in particular in the cylindrical wall 90 and for example in fluidic communication with the port(s) 120. The tub 130 is in particular in fluidic communication with the gutter 110.

[0058] The tub 130 is for example suitable for collecting oil that may flow down the cylindrical wall 90. At least one of the first orifices 81 opens directly into the tub 130. At least two or three (here three) adjacent first orifices 81 open directly into the tub 130.

[0059] The housing 70 may include at an axial end 70a, in particular downstream, an annular mounting flange 140, which extends in particular perpendicularly to the axis A and which includes, for example, axial holes 141 adapted to receive fastening elements. These fastening elements allow, in particular, the housing 70 to be fixed to the electrical machine 160 and in particular to the stator 170 of the electrical machine 160.

[0060] The radial wall 80 includes, for example, axial through holes 85 suitable for receiving fasteners. These fasteners allow, in particular, the housing 70 to be fixed to the bearing 50 and especially to the bearing support 55. Each of the holes 85 in the radial wall 80 is interposed, in particular, between two first orifices 81, and Each of the first orifices 81 is in particular intercalated between two holes 85 of the radial wall 80. Some of the holes 85 (and in particular each of the holes 85) of the radial wall 80 are located for example between two adjacent conduits 100 and the gutter 110.

[0061] Thus, the oil recovery casing 70 of the invention makes it possible, in particular, to: - to make the mechanical connection between bearing 50 and electrical machine 160; - to circulate a flow of oily gas from the area of ​​the electrical machine 160 up to chamber 60 to pressurize the latter; and - to recover the accumulated oil, brought by the flow of oily gas and recycle it.

Claims

Demands

1. An annular oil recovery housing (70) for a turbomachine (10), particularly an aircraft turbomachine, said housing (70) extending about an axis (A) and comprising: - a radial annular wall (80) extending perpendicularly to the axis (A) and comprising an annular row of first orifices (81) oriented axially, - a cylindrical wall (90) extending about the axis (A) and comprising an annular row of second orifices (91) oriented radially, the cylindrical wall (90) being connected to an inner periphery (82) of the radial wall (80), - angled conduits (100) distributed about the axis (A) and the cylindrical wall (90) and connected to the radial (80) and cylindrical (90) walls, each of these conduits (100) connecting one of the first orifices (81) to one of the second orifices (91),characterized in that it further comprises: - at least one circular arc gutter (110) extending around the axis (A) and connected to a portion of said conduits (100) to be capable of collecting oil accumulated in these conduits (100), and - at least one discharge port (120) in fluidic communication with the gutter (110) and capable of discharging the collected oil to the outside of the crankcase (70).

2. Housing (70) according to claim 1, wherein the housing (70) is formed in one piece.

3. Carter (70) according to claim 1 or 2, wherein the gutter (110) has an angular extent around the axis (A) between 150 and 200°, and preferably of the order of 180°.

4. Carter (70) according to any one of the preceding claims, wherein said at least one port (120) is located in the middle of the gutter (110), that is, midway between circumferential ends (110a, 110b) of the gutter (110).

5. Housing according to any one of the preceding claims, wherein the gutter (110) has a first circumferential end (110a) located at 3 o'clock, and a second circumferential end (110b) located at 9 o'clock, and the gutter (110) extends over a lower half of the housing (70), 3 o'clock and 9 o'clock being angular positions around the axis (A) with reference to the dial of a clock.

6.

7. Carter (70) according to claim 5, wherein the port is located at 6 o'clock. Carter (70) according to any one of the preceding claims, wherein it further comprises a tub (130) formed in the cylindrical wall (90) and in fluidic communication with said at least one port (120), or even also with the gutter (110), the tub (130) being able to collect oil that may flow down the cylindrical wall (90).

8. Carter (70) according to claim 7, wherein at least one of the first orifices (81) opens directly into the bathtub (130).

9. Carter (70) according to claim 8, wherein at least two or three first adjacent orifices (81) open directly into the bathtub (130).

10. Carter (70) according to any one of the preceding claims, wherein the number of conduits (100) is between 10 and 30, and preferably between 15 and 25.

11. Carter (70) according to any one of the preceding claims, wherein each of the conduits (100) has a parallelepiped shape in cross-section.

12. A housing (70) according to any one of the preceding claims, wherein it comprises at an axial end (70a) an annular fixing flange (140), which extends perpendicularly to the axis (A) and which includes axial holes (141) suitable for receiving fixing elements.

13. Housing (70) according to any one of the preceding claims, wherein said radial wall (80) includes axial through holes (85) suitable for receiving fastening elements.

14. Housing (70) according to claim 13, wherein each of the holes (85) in the radial wall (80) is intercalated between two first orifices (81), and each of the first orifices (81) is intercalated between two holes (85) in the radial wall (80).

15. Exhaust module (150) for a turbomachine, in particular for aircraft, comprising an oil recovery casing (70) according to any one of the preceding claims, the oil recovery casing (70) being surrounded by an exhaust casing (28) comprising two coaxial annular walls (28a, 28b) which define between them a flow channel of an exhaust gas stream and which are connected to each other by radial arms (35), the oil recovery casing (70) being axially interposed between at least one bearing (50) of which an outer ring (51) is connected to the exhaust casing (28) and the oil recovery casing (70), and an electric machine (160) of which a stator (170) is connected to the oil recovery casing (70).