Turbine equipped with heat exchanger and having recovery cycle

Abstract

The invention relates to an aircraft turbine (10) with a recovery cycle, comprising:-a heat exchanger (6) comprising a first circuit (62) having an inlet (622) connected to an outlet (444) of a flow channel (44) of a turbine (4) and a second circuit (64) having an inlet (642) connected to an exhaust system (20) and an air outlet (644); -at least one duct (7) extending from the turbine housing (40) to the bearing enclosure (5) for passage of the auxiliary device (S); and-air circulation means (8) comprising a first passage (82) having a first upstream end (822) connected to the system (20) and a first downstream end (824) connected to the inlet (642), and a second passage (84) having a second downstream end (844) connected to the outlet (644), and wherein the duct (7) extends radially outward to the means (8).

Description

Field of the Invention

[0001] The present invention relates to the field of aircraft turbines having a recuperative cycle, which particularly includes a heat exchanger. Background Art

[0002] The prior art includes the documents EP-A2-1589204, GB-A-1084889, FR-A1-3036437, US-A-3339364 and FR-A-1452128.

[0003] As Figure 1 shown, the aircraft turbine 10 includes a gas generator which, in the gas flow direction from upstream to downstream, includes at least one compressor 2, an annular combustion chamber 3 and at least one turbine 4. The compressor 2 is supplied with air and compresses the air. The compressed air is mixed with fuel and burned in the combustion chamber 3, which supplies combustion gases to the turbine 4. These combustion gases expand in the turbine 4 and drive the rotation of the rotor 42 of the turbine, which in turn drives the rotor of the compressor 2 via a common shaft.

[0004] The turbine 10 may be equipped with one or more rotor groups, each rotor group including a rotor of the compressor 2 connected to the rotor of the turbine 4 by a shaft.

[0005] There are also turbines in which a free turbine 4b is installed downstream of one or more rotor groups of the turbine. As long as the rotor of the turbine is not connected to the compressor rotor by a shaft, then the turbine is a free turbine.

[0006] Therefore, it should be understood that the turbine may include a plurality of consecutive compressors (e.g., a low-pressure compressor, followed by a high-pressure compressor), and a plurality of consecutive turbines (e.g., a high-pressure turbine, followed by a free turbine or a low-pressure turbine).

[0007] The turbine may be a turboprop engine (such as an aircraft and an unmanned aerial vehicle) and a turboprop engine (such as a helicopter engine, an auxiliary power unit or an APU).

[0008] In the present application, a turbine having a conventional cycle is defined as a turbine in which the compressed air leaving the compressor is directly supplied to the combustion chamber.

[0009] In contrast, a turbine having a recuperative cycle (as Figure 1 shown) is a turbine in which the combustion gases G flowing out of the turbines 4, 4b are used to heat the compressed air F leaving the compressor 2. The air Fc heated by the gas G is intended to be supplied to the combustion chamber 3. This technology makes it possible to improve the performance of the turbine because the amount of fuel required to reach the operating temperature of the turbine is less than the amount required within the scope of a turbine having a conventional cycle.

[0010] Thus, it is advantageous to integrate the heat exchanger 6 into a structural element of the turbine 4b in order to recover the residual energy at the outlet of the turbine 4 and heat the compressed air F upstream of the combustion chamber 3. To this end, with reference to Figure 2 , the exchanger 6 extends radially outside the annular casing 40 of the turbine 4. The exchanger 6 includes a first circuit 62 that is connected to the outlet 444 of the annular flow passage 44 for recovering the turbine gas G. The exchanger 6 includes a second circuit 64 that is connected to the system 20 for collecting the compressed air F from the compressor 2 ( Figure 1 ), and the air Fc heated by the gas G in the exchanger is conveyed upstream to the combustion chamber 3. At the exchanger 6, at least some of the gas G is released into the atmosphere via the outlet 63, in particular by passing through the exhaust nozzle of the turbine.

[0011] One of the drawbacks of integrating this heat exchanger into the turbine is that the heat exchanger is close to other elements of the turbine, especially the auxiliary devices. In fact, the turbine includes auxiliary devices S for operating the rear bearing of the turbine. These auxiliary devices straddle the annular flow passage 44 of the turbine. It is not easy to integrate the exchanger 6 in this area because the auxiliary devices may interfere with the exchange of the air F, Fc entering and leaving the exchanger 6.

[0012] In this case, it is interesting to overcome the drawbacks of the prior art by proposing an arrangement of auxiliary devices that is suitable for the presence of a heat exchanger in a turbine with a recovery cycle to limit the pressure loss or efficiency of the air exchange entering and leaving the heat exchanger while ensuring the auxiliary device function of the bearing. Summary of the Invention

[0013] The present invention provides a simple, effective and economical solution to at least some of the above problems.

[0014] To this end, the present invention proposes an aircraft turbine with a recovery cycle, the aircraft turbine comprising:

[0015] - at least one compressor centered on the axis X of the turbine,

[0016] - an annular combustion chamber extending around the axis X,

[0017] - at least one turbine centered on the axis X, which defines an annular flow passage for the gas flow,

[0018] - an annular casing of the bearing for guiding at least one rotor of the turbine, the annular casing being radially positioned inside the annular flow passage,

[0019] - A heat exchanger, which is radially positioned outside the annular flow passage and includes two circuits: a first circuit of the exchanger, the first circuit including an inlet connected to the outlet of the annular flow passage; and a second circuit of the exchanger, the second circuit including an air inlet connected to a collection system of compressed air from a compressor, and an air outlet.

[0020] - An annular turbine housing, which extends around the turbine flow passage, and

[0021] - At least one pipe of the auxiliary device passage, the at least one pipe extending radially from the turbine housing to the annular enclosure of the bearing with respect to the axis X.

[0022] According to the invention, the turbine further includes an annular air circulation device, which extends around the annular flow passage of the turbine and includes two coaxial annular passages: a first passage of the device, the first passage including a first upstream end connected to the collection system and a first downstream end connected to the air inlet of the second circuit of the exchanger; and a second passage of the device, the second passage including a second downstream end connected to the air outlet of the second circuit of the exchanger.

[0023] According to the invention, the at least one pipe extends radially outward to the annular air circulation device.

[0024] Therefore, this solution enables the above object to be achieved. Due to the annular air circulation device, it is possible to minimize the pressure loss or the loss of air exchange efficiency in the second circuit of the exchanger while maintaining the auxiliary device function of the annular enclosure of the bearing. In addition, one or more pipes of the auxiliary device passage are integrated together, so as not to interfere with the air flow in the first passage and the second passage of the annular air circulation device.

[0025] Therefore, the new configuration of one and more pipes of the auxiliary device passage and the annular air circulation device is conducive to the exchange of air F, Fc and gas G between the exchanger and other components of the turbine. For this purpose, the device of the invention is connected to the second circuit of the exchanger, wherein, on the one hand, the first passage is configured to supply compressed air F obtained by the collection system from the compressor to the exchanger, and on the other hand, the second passage is configured to redistribute the air Fc heated by the gas G (from the first circuit of the exchanger) upstream of the device (especially upstream of the combustion chamber). At least some of the gas G from the first circuit of the exchanger is configured to leave the exchanger, for example, via the exhaust nozzle of the turbine, especially to the outside of the turbine.

[0026] Therefore, the advantage of the invention is to provide a simple design, which is highly reliable and has little impact on the cost and space requirements in the turbine.

[0027] The guiding element according to the invention may comprise one or more of the following features taken in isolation from one another or in combination with one another:

[0028] - The at least one duct comprises a radially outer end portion which comprises a connecting end piece and which is connected to an annular air circulation device, for example, the radially outer end portion is connected to the annular air circulation device by means of an annular linear connecting piece;

[0029] - At least one seal is received in a groove of the radially outer end portion;

[0030] - The at least one duct passes through a radial opening or orifice in the annular air circulation device, the opening or orifice extending radially over the entire thickness of the device;

[0031] - The first and second passages of the annular air circulation device diverge downstream and each comprise a channel cross-section which increases from the upstream axial end of the first and second passages towards the downstream axial end of the first and second passages;

[0032] - The annular air circulation device comprises three coaxial annular walls which delimit therebetween the first and second passages, each of these walls comprising a fastening flange or a sealing member at the axial ends of each wall;

[0033] - The annular air circulation device has an outer diameter DE at its upstream end 8 , the outer diameter of the annular air circulation device being between the inner diameter DI of the downstream end of the annular air circulation device 844 and the outer diameter DE 824 , for example, the outer diameter of the annular air circulation device being between the diameter D 87 , D 85 of the downstream ends of the dividing wall and the inner wall of the annular air circulation device;

[0034] - The annular turbine housing comprises at least one channel orifice of the at least one duct;

[0035] - The radial dimension H of the at least one duct of the auxiliary device channel 7 is between 110 mm and 170 mm, preferably, the radial dimension H 7 is between 150 mm and 160 mm;

[0036] - The at least one duct of the auxiliary device channel has an outer diameter DE between 6 mm and 10 mm 7 and an inner diameter DI between 4 mm and 8 mm 7 .

[0037] The present invention also relates to an aircraft, which includes at least one turbine with a recovery cycle according to one of the features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be better understood from the following description given by way of non - limiting example and with reference to the drawings, and other details, features and advantages of the present invention will become more apparent, in which:

[0039] Figure 1 is a schematic axial sectional view of a turbine with a recovery cycle in the prior art,

[0040] Figure 2 is Figure 1 an enlarged schematic partial axial sectional view of the ducts of the auxiliary device passage and the heat exchanger in the turbine of

[0041] Figure 3 is a schematic axial sectional view of a turbine with a recovery cycle according to the present invention,

[0042] Figure 4 is Figure 3 a schematic axial cross - sectional view of the ducts of the auxiliary device passage of the turbine of

[0043] Figure 5 is according to the first embodiment of Figure 3 a schematic perspective view of the annular air circulation device of the turbine of

[0044] Figure 6 is Figure 3 an enlarged schematic partial axial sectional view of the turbine shown in Figure 5 which includes ducts of the auxiliary device passage arranged in the annular air circulation device shown in Figure 4 shown in

[0045] Figure 7 is according to the second embodiment of Figure 3 a schematic perspective view of the annular air circulation device of the turbine of

[0046] Figure 8 is Figure 3 an enlarged schematic partial axial sectional view of the turbine in Figure 7 which includes ducts of the auxiliary device passage arranged in the annular air circulation device shown in Figure 4 shown in

[0047] Elements having the same function in different embodiments have the same reference numerals in the drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] By convention, in the following description, the terms "longitudinal" and "axial" refer to the orientation of structural elements extending in the direction of a longitudinal axis (such as the longitudinal axis of an engine of a turbine). The terms "radial" or "vertical" refer to the orientation of structural elements extending along a direction perpendicular to the longitudinal axis. The terms "inner" and "outer" and "internal" and "external" are used for positioning relative to the longitudinal axis. Thus, a structural element extending along the longitudinal axis includes an inner surface facing the longitudinal axis and an outer surface opposite the inner surface of the structural element.

[0049] Similarly, by convention, in the present application, the terms "upstream" and "downstream" are defined relative to the direction of gas flow in the turbine.

[0050] Figure 1 and Figure 2 As already described above and shown, there is a prior art turbine 10 with a recovery cycle, in which one or more pipes 7 of the auxiliary device S-channel pass through the annular flow passage 44 supplying the turbine 4b on the one hand and through the second circuit 64 of the heat exchanger 6 on the other hand.

[0051] The present invention is applicable to an aircraft turbine 10 with a recovery cycle. A non-limiting example of the turbine 10 is shown in Figure 3 as a turboprop engine.

[0052] The turbine 10 extends along a longitudinal axis X. The turbine 10 includes at least one compressor 2 (e.g., Figure 3 a high-pressure compressor in Figure 3 ), an annular combustion chamber 3, and at least one turbine 4, 4b (e.g.,

[0053] a high-pressure turbine 4 and a free turbine 4b in

[0054] The compressor 2 and the turbine 4 can be annular. The compressor 2 and the turbine 4 are centered on the axis X of the turbine. The combustion chamber 3 extends around the axis X. The compressor 2 includes a collection system 20 for compressed air F (e.g., via a compressed air F collection pipe or cavity at the outlet of the compressor 2).

[0055] In Figure 3 the example shown, the compressor 2 is connected to the turbine 4 by a drive shaft 24. The free turbine 4b drives the power shaft 1b via a through drive shaft 1a and a power shaft 1. The through shaft 1a and the power shaft 1b are engaged with the reduction gear 1 via pinions 1c, 1d.

[0056] The turbine 4 includes an annular turbine housing 40, at least one rotor 42, and an annular flow passage 44 for gas flow. One or more rotors 42 may extend around a drive shaft 24. The annular housing 40 extends around the annular flow passage 44. The annular flow passage 44 may extend between the annular housing 40 and the rotor 42.

[0057] The annular flow passage 44 includes an inlet 442 (specifically for the gas G from the combustion chamber 3) and an outlet 444 (specifically for the gas G in the direction of the heat exchanger 6 (described below)).

[0058] The turbine 10 includes an annular enclosure 5 for guiding one or more bearings P of one or more rotors 42. The annular enclosure 5 is radially positioned inside the annular flow passage 44.

[0059] The turbine 10 includes at least one or more pipes 7 for an auxiliary device S passage. One or more pipes 7 extend radially from the annular enclosure 5 of one or more bearings (P) relative to the axis X to the turbine housing 40 ( Figure 6 ).

[0060] Figure 4 An example of the pipe 7 is shown. The pipe 7 may extend between a radially outer end 720 and a radially inner end 722 (e.g., relative to the axis X). The radially outer end 720 may include a first connection end piece 721. The first connection end piece 721 may be configured to be attached to a fluid supply pipe for the auxiliary device (S) and is located outside the turbine 4 (not shown). For this purpose, the first connection end piece 721 may include a thread for connecting to the supply pipe. The radially inner end 722 may include a second connection end piece 723, which is configured to be fixed to the annular enclosure 5. For this purpose, the second connection end piece 723 may include a thread for connecting to the annular enclosure 5.

[0061] The pipe 7 may include an intermediate portion 724 connecting the radially outer end 720 and the radially inner end 722.

[0062] The first connection end piece 721 may include a shoulder 726. Figure 4 Two shoulders 726 are shown at the first connection end piece 721. One or more grooves 727 may be formed between the shoulders 726. The first connection end piece 721 may further include a collar 728 extending radially outward from the shoulder 726.

[0063] The pipe 7 may have a radial dimension H 7 . The pipe 7 may have a first outer diameter DE 7 and a first inner diameter DI 7 .

[0064] The turbine 10 includes a heat exchanger 6. The exchanger 6 is positioned radially outside the annular flow passage 44.

[0065] The exchanger 6 includes two circuits: a first circuit 62 and a second circuit 64.

[0066] The first circuit 62 includes an inlet 622 that is connected to the outlet 444 of the annular flow passage 44. The first circuit 62 is configured to supply gas G to the exchanger 6.

[0067] The first circuit 62 may further include an outlet 632 that enables at least some of the gas G to leave the exchanger 6 towards the outside of the turbine. For example, the gas G may leave via an exhaust nozzle of the turbine, in which case the outlet 632 for the gas G is connected to the exhaust nozzle.

[0068] The second circuit 64 includes an air inlet 642 and an air outlet 644. The air inlet 642 is connected to a collection system 20 of compressed air F in the compressor 2. The second circuit 64 is configured to first supply a stream of compressed air F from the collection system 20 to the exchanger 6, and secondly to convey an air stream Fc heated by the gas G in the exchanger 6 (particularly upstream of the combustion chamber 3). Thus, the stream of compressed air F is heated by at least some of the gas G from the first circuit 62 to form a heated air stream Fc.

[0069] A particular feature of the invention is that the turbine 10 further includes an annular air circulation device 8.

[0070] Figures 4 to 8 A plurality of different embodiments of the annular air circulation device 8 for the turbine 10 are shown.

[0071] Reference Figure 5 and Figure 6 , a first embodiment of the annular air circulation device 8 will now be described.

[0072] The device 8 may be an annular rotary member extending around a longitudinal axis B. This axis B is substantially parallel to the axis X (or inclined, for example, at an angle between 5° and 45° relative to the axis X in Figure 6 ).

[0073] The device 8 includes two coaxial annular passages: a first passage 82 and a second passage 84.

[0074] The first passage 82 may extend between a first upstream axial end 822 and a first downstream axial end 824. In particular, the first passage 82 is in fluid communication with the inlet 642 and the collection system 20 such that a stream of compressed air F can be supplied to the exchanger 6.

[0075] The second passage 84 may extend between a second downstream axial end 844 and a second upstream axial end 842. In particular, the second passage 84 is in fluid communication with the air outlet 644 and the upstream side of the combustion chamber 3 so as to be able to redistribute the heated air flow Fc from the exchanger 6 to the upstream side of the combustion chamber 3.

[0076] The first passage 82 and the second passage 84 may diverge downstream and each include a channel cross-section that increases from their upstream axial ends 822, 842 to their downstream axial ends 824, 844.

[0077] The device 8 includes three coaxial annular walls, namely an inner annular wall 85, an outer annular wall 86 and a partition wall 87. The partition wall 87 extends between the inner wall 85 and the outer wall 86.

[0078] The outer wall 86 and the partition wall 87 define the first passage 82 therebetween. The inner wall 85 and the partition wall 87 define the second passage 84 therebetween.

[0079] In Figure 5 the illustrated example, the three annular walls 85, 86, 87 and the two passages 82, 84 are a single piece (i.e., made of the same material).

[0080] The inner wall 85 may include a first fastening flange 852 (especially at the upstream axial end of the inner wall), and / or a second fastening flange 854 (especially at the downstream axial end of the inner wall). Alternatively (not shown), the inner wall 85 may include a first sealing member at its upstream axial end and / or its downstream axial end. For example, the first sealing member may be a flange fixed with a seal or without a seal.

[0081] The outer wall 86 may include a third fastening flange 862 (especially at the upstream axial end of the outer wall), and / or a fourth fastening flange 864 (especially at the downstream axial end of the outer wall). Alternatively (not shown), the outer wall 86 may include a second sealing member at its upstream axial end and / or its downstream axial end. For example, the second sealing member may be an edge fixed with a seal or without a seal.

[0082] The partition wall 87 may include a third sealing member 872 (especially on the upstream axial end of the partition wall), and / or a fourth sealing member 874 (especially on the downstream axial end of the partition wall). For example, these third and fourth sealing members may be edges fixed with a seal or without a seal. Alternatively (not shown), the partition wall 87 may include fastening flanges at its upstream axial end and / or its downstream axial end.

[0083] The inner wall 85, the outer wall 86, and the partition wall 87 may each have a first diameter D at their downstream ends. 85 , a second diameter D 86 and a third diameter D 87 .

[0084] As Figure 6 shown, the device 8 may have a second outer diameter DE at its upstream end. 8 This second outer diameter DE 8 may be between the first diameter D 85 and the third diameter D 87 . The device 8 may have a third outer diameter DE 824 and a second inner diameter DI 844 at its downstream end. The second outer diameter DE 8 may be between the third outer diameter DE 824 and the second inner diameter DI 844 .

[0085] In Figure 6 the example shown, the first diameter D 85 is substantially the same as the inner diameter DI 844 , and the second diameter D 86 is substantially the same as the outer diameter DE 824 .

[0086] The device 8 may include one or more openings 80 (or orifices 81) that extend radially through the entire thickness of the device 8. The thickness of the device 8 is measured in a plane perpendicular to the axis B (or axis X).

[0087] Now reference will be made to Figure 6 describe the annular air circulation device 8 of the first embodiment assembled in the turbine 10.

[0088] In the turbine 10, the device 8 extends around the annular flow passage 44, particularly around the annular turbine housing 40.

[0089] The first upstream axial end 822 of the first passage 82 of the device 8 is connected to the collection system 20, and the first downstream axial end 824 is connected to the air inlet 642 of the second circuit 64 of the exchanger 6. The second downstream axial end 844 of the second passage 84 of the device 8 is connected to the air outlet 644 of the second circuit 64 of the exchanger 6. The second upstream axial end 842 may open downstream to the combustion chamber 3.

[0090] Another feature of the present invention is that one or more pipes 7 extend radially outward (relative to the axis X) to the annular air circulation device 8.

[0091] In Figure 6In the exemplary component shown, a pipe 7 extends from an annular housing 5 to a device 8. In particular, a first connection end piece 721 of the pipe 7 extends into an opening 80 of the device 8 (at an inner wall 85), and a second connection end piece 723 extends into the annular housing 5. An intermediate portion 724 of the pipe 7 passes through an annular flow channel 44.

[0092] The annular housing 40 may include at least one channel orifice 400 for the pipe 7. The channel orifice 400 may be substantially aligned with the opening 80 in a plane perpendicular to the axis X.

[0093] According to Figure 6 the component shown, the pipe 7 is connected to the annular housing 5, for example, by a threaded connector 98 that has threads formed on a radially inner end 722.

[0094] For example, the pipe 7 (particularly a radially outer end 720) may be in contact with the annular housing 40 by means of an annular linear connector 90. In particular, the radially outer end 720 includes two bearing surfaces (such as at a shoulder 726 and a collar 728) to form the annular linear connector.

[0095] An "annular linear connector" is defined as a connector between a spherical member (i.e., the two bearing surfaces at the shoulder 726 and the collar 728 of the radially outer end 720) and a cylindrical member (i.e., the annular housing 40 at the channel orifice 400).

[0096] In this way, the annular linear connector may allow the radially outer end 720 of the pipe 7 to translate along the axis Y relative to the channel orifice 400, and / or allow the radially outer end 720 of the pipe 7 to bend along the axis X and a circumferential axis Z while remaining guided in the channel orifice 400. The axis Y may be substantially perpendicular to the axis X. The axis Z may be substantially transverse to the axis X.

[0097] At the second connection end piece 723, a conical seal 99 may be arranged to provide a seal with the annular housing 5. In the region of the shoulder 726, two segmented seals 94, 95 may be arranged to provide a seal with the annular housing 40. These seals 94, 95 may be located in a groove 727. At the collar 728, the pipe 7 may be locked against rotation, where a splined flange 96 enables the pipe 7 to slide on the collar 728 (which is also splined). A bushing 92 (which may be a wear part) may be assembled on a bearing surface at the seals 94, 95.

[0098] The threaded connector 98 and the annular linear connector 90 enable one or more pipes 7 to expand freely in a turbine.

[0099] The first connecting end member 721 may include threads for fixing the pipe 7 to an external supply pipe, thereby achieving the continuity of the pipe 7 in the S-channel of the auxiliary device. In Figure 6 the example shown, the external supply pipe is configured to pass through the opening 80 to be fixed to the first connecting end member 721 located at the opening 80 of the device 8.

[0100] At the first connecting end member 721, a gasket may be assembled so that the entire pipe 7 of the auxiliary device channel can be sealed.

[0101] The radial dimension H of the pipe 7 in the S-channel of the auxiliary device 7 is between 110 mm and 170 mm. In particular, in Figure 6 it, the radial dimension H 7 is between 110 mm and 120 mm.

[0102] The first outer diameter DE of the pipe 7 7 may be between 6 mm and 10 mm. Preferably, the first outer diameter DE 7 is between 8 mm and 9 mm. The first inner diameter DI of the pipe 7 7 may be between 4 mm and 8 mm. Preferably, the first inner diameter DI 7 is 6 mm.

[0103] In one or more components of the pipe 7 and the device 8 in the first embodiment ( Figure 6 ), compressed air F (from the compressor 2) is drawn out by the collection system 20 and conveyed to the exchanger 6 via the first passage 82 of the device 8.

[0104] The combustion gas G (leaving the combustion chamber 3 and the turbine 4) flows into the annular flow channel 44 and is conveyed to the exchanger 6 through the first circuit 62. At least some of the gas G is used to heat the compressed air F in the exchanger 6. Then, the air Fc heated by the gas G is conveyed through the second passage 84 of the device 8, particularly upstream of the combustion chamber 3. Another part of the gas G may be discharged from the turbine.

[0105] Figure 7 and Figure 8 show a second embodiment of the annular air circulation device 8 assembled in the turbine 10 according to the present invention.

[0106] The device 8 of the second embodiment is different from the device 8 of the first embodiment in that the first connecting end member 721 of the pipe 7 is fixed to the device 8 (instead of being fixed to Figure 6 the annular housing 40).

[0107] To achieve this, an annular linear connecting member 90 (which may include a spline flange 96 and segmented seals 94, 95) may be located in the device 8.

[0108] In particular, the annular linear connector 90 is located at the outer wall 86 and / or the first passage 82 of the device 8.

[0109] In Figure 8 In the illustrated example, at least a portion of the radially outer end 720 passes through the orifice 81, and the annular linear connector 90 is located at the outer wall 86 and the first passage 81. The first connection end member 721 extends at least partially outward from the outer wall 86. This enables connection to an external supply pipe and does not interfere with the exchange of air F, Fc in the second circuit 64 of the exchanger 6.

[0110] In addition, the duct 7 of the second embodiment differs from the duct 7 of the first embodiment in the radial dimension H 7 . The radial dimension H of the duct 7 in the second embodiment 7 can be between 140 mm and 160 mm. Additionally, in Figure 7 the illustrated example, the middle portion 724 of the duct 7 passes at least partially through the annular flow path 44 and the annular housing 40, and the radially outer end 720 passes at least partially through the first passage 82 and the second passage 84.

[0111] Increasing the radial dimension H of the duct in the second embodiment 7 enables the first connection end member 721 to be radially positioned on the outermost side farthest from the device 8. This enables the first connection end member 721 to be assembled with a supply pipe outside the turbine 4 and further reduces the blockage that may occur due to one or more ducts 7 passing through the first passage 82 and the second passage 84 and the annular flow path 44. In this way, the exchange of air F, Fc between the device 8 and the second circuit 64 of the exchanger is more efficient.

Claims

1. An aircraft turbine (10) having a recycling loop, said aircraft turbine comprising: - at least one compressor (2) centered on the axis (X) of the turbine, - an annular combustion chamber (3) extending around the axis (X), - at least one turbine (4) centered on the axis (X), the turbine defining an annular flow passage (44) for gas flow, - an annular casing (5) of a bearing (P) for guiding at least one rotor (42) of the turbine, the annular casing (5) being radially positioned inside the annular flow passage (44), - a heat exchanger (6), the heat exchanger being radially positioned outside the annular flow passage (44) and comprising two circuits: a first circuit (62) of the exchanger, the first circuit comprising an inlet (622) connected to an outlet (444) of the annular flow passage (44); and a second circuit (64) of the exchanger, the second circuit comprising an air inlet (642) connected to a collection system (20) of compressed air from the compressor (2), and an air outlet (644), - an annular turbine casing (40) extending around the annular flow passage (44), and - at least one duct (7) of a passage for auxiliary means (S), the at least one duct extending radially from the turbine casing (40) to the annular casing (5) of the bearing relative to the axis (X), characterized in that the turbine (10) further comprises an annular air circulation device (8) extending around the annular flow passage (44) of the turbine and comprising two coaxial annular passages: a first passage (82) of the device, the first passage comprising a first upstream axial end (822) connected to the collection system (20) and a first downstream axial end (824) connected to the air inlet (642) of the second circuit (64) of the exchanger; and a second passage (84) of the device, the second passage comprising a second downstream axial end (844) connected to the air outlet (644) of the second circuit (64) of the exchanger, and wherein the at least one duct (7) extends radially outwards to the annular air circulation device (8), and wherein the at least one duct (7) comprises a radially outer end (720), the radially outer end comprising a connecting end piece (721), and the radially outer end is connected to the annular air circulation device (8).

2. The turbine according to claim 1, characterized in that the radially outer end (720) is connected to the annular air circulation device (8) by an annular linear connector (90).

3. The turbine according to claim 2, characterized in that at least one seal (94, 95) is received in a groove (727) of the radially outer end (720).

4. The turbine according to at least one of claims 1 to 3, characterized in that The at least one duct (7) passes through a radial opening (80) or orifice (81) of the annular air circulation device (8), the opening (80) or orifice (81) extending radially over the entire thickness of the device (8).

5. The turbine according to at least one of the preceding claims, characterized in that the first and second passages (82, 84) of the annular air circulation device (8) diverge downstream and each comprise a channel cross-section increasing from the upstream axial ends (822, 842) of the first and second passages to the downstream axial ends (824, 844) of the first and second passages.

6. The turbine according to at least one of the preceding claims, characterized in that the annular air circulation device (8) comprises three coaxial annular walls (85, 86, 87) which define therebetween the first and second passages (82, 84), each of these walls (85, 86, 87) comprising at each of its axial ends (822, 824, 842, 844) a fastening flange (852, 854, 862, 864) or a sealing member (872, 874).

7. The turbine according to claim 6, characterized in that The annular air circulation device (8) has an outer diameter (DE 8 ) at its upstream end, and the outer diameter of the annular air circulation device is between the inner diameter (DI 844 ) and the outer diameter (DE 824 ) of the downstream end of the annular air circulation device. The outer diameter of the annular air circulation device is, for example, between the diameters (D 87 , D 85 ) of the downstream ends of the partition wall (87) and the inner wall (85) of the annular air circulation device.

8. The turbine according to at least one of the preceding claims, characterized in that the annular turbine housing (40) comprises at least one channel orifice (400) for the at least one duct (7).

9. The turbine according to at least one of the preceding claims, characterized in that The radial dimension (H 7 ) of the at least one pipe (7) of the auxiliary device (S) channel is between 110 mm and 170 mm, preferably, the radial dimension (H 7 ) is between 150 mm and 160 mm.

10. The turbine according to at least one of the preceding claims, characterized in that The at least one pipe (7) of the auxiliary device (S) channel has an outer diameter (DE) between 6 mm and 10 mm 7 ), and an inner diameter (DI) between 4 mm and 8 mm 7 .

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