Annular assembly for a turbine wheel of a turbomachine

Abstract

This document relates to an annular assembly for a turbine of a turbomachine, in particular of an aircraft, extending around a longitudinal axis X and comprising: a distributor fixed to an outer casing; a blade disc mounted so as to rotate inside the outer casing; the blade disc being surrounded by a circumferential segmented ring, the circumferential segmented ring being carried by the outer casing and formed by a vault and an annular deflector arranged radially outside the blade disc, the annular deflector being carried by an upstream edge of the vault and extending radially inwards from the upstream edge of the vault; characterized in that it comprises sealing members (56) between two circumferentially adjacent ring segments, these sealing members (56) comprising a first circumferential sealing member (58) between two circumferentially consecutive deflector segments.

Description

Technical Field

[0001] This article relates to a sealing component for turbines, and more specifically for low-pressure turbines. Background Technology

[0002] Typically, a turbine consists of a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine, and a low-pressure turbine, arranged from upstream to downstream. The low-pressure turbine makes it possible to utilize and release the power generated in the combustion chamber located upstream of the low-pressure turbine. Two airflows within the turbine need to be considered: the primary annular flow and the secondary annular flow. The secondary flow bypasses all the hot parts of the turbine. The other flow (called the main flow) originates from the low-pressure compressor, passes through the entire turbine to the low-pressure turbine, and is surrounded by the secondary airflow. This main flow circulates within the main flow duct.

[0003] The turbine consists of alternating annular rows of stator blades and moving blades arranged inside the casing. Figure 1 A portion of this turbine 1 is shown, along with the downstream annular row of the upstream distributor 2 and the moving blades 4.

[0004] Distributor 2 includes an outer annular platform 6 fixed to radial blades 8. The row of movable blades 4 includes an outer annular platform 10, from which lugs 12 extend radially outward. These lugs cooperate in a sealing manner with wearable components 14, such as those in a honeycomb form, belonging to a segmented ring supported by housing 16. Figure 1 As shown.

[0005] The circumferentially segmented ring includes an arch 18 supporting a wearable element 14 on its radially inner surface 14. The ring also includes a thermal deflector 20 supported by the upstream end of the arch 18. The arch 18 is secured to the turbine housing 16 by a C-shaped clamping tab 22 integral with the upstream end of the external platform of a distributor located downstream of the moving wheel. The upstream end of the arch includes a C-shaped component 24, a cylindrical track 26 for securing the ring to the housing 16, and a radial arm 28 for securing to the upstream distributor 2. The deflector 20 is attached to the upstream edge 30 of the arch 18 and extends radially inward.

[0006] When the turbine is in operation, combustion gases flow from upstream to downstream through the turbine's main duct, and a portion of the hot combustion air may escape between the downstream end of the outer platform 6 of the distributor 2 and the upstream end of the outer platform 10 of the downstream moving wheel 4. The annular space formed in this way and labeled J corresponds to the space required for the rotation of the moving wheel.

[0007] To restrict the passage of hot air between the two vault sections 18, a tongue is used, which partially engages in the vault section 18 and partially engages in the circumferentially adjacent vault section 18.

[0008] However, air may still circulate between the two sections of the deflector 20 and damage the attachments to the housing, namely the C-shaped component 24, the cylindrical track 26 of the housing 16, the radial arm 28 of the upstream deflector 20, and the housing 16 itself.

[0009] The use of a protruding tongue is not feasible because the thickness of the deflector is too small to be considered as a solution.

[0010] This article aims to address these shortcomings in a reliable, effective, and inexpensive manner. Summary of the Invention

[0011] This document relates to an annular assembly for a turbine in an aircraft, particularly an annular assembly extending in the axial direction X and comprising:

[0012] - Distributor, which is fixed to the outer housing;

[0013] - A blade disk, which is arranged downstream of the distributor and mounted to rotate inside the outer housing;

[0014] - The blade disk is surrounded by circumferentially segmented rings, the blade disk is supported by an outer housing and formed by an arch and annular deflector arranged radially to the outside of the blade disk, the annular deflector being supported by the upstream edge of the arch and extending radially inward from the upstream edge of the arch, characterized in that it includes a sealing member between two circumferentially adjacent annular segments, the sealing member including a first circumferential sealing member between two circumferentially continuous deflector segments.

[0015] This sealing element provides an improved pneumatic thermal seal between the thermal deflector sections. The sealing element makes it possible to provide thermal protection to the housing by preventing leakage of hot combustion gases from the circumferential joint area of ​​the thermal deflector sections.

[0016] The first circumferential sealing member can be arranged at the junction between two circumferentially continuous deflector sections.

[0017] The sealing component may include a second circumferential sealing member between two circumferentially continuous dome sections, which engage with the first sealing member.

[0018] The second sealing member makes it possible to prevent combustion gases from leaking between the two circumferentially continuous dome sections. The connection between the second sealing member and the first sealing member facilitates the assembly of the sealing components. Therefore, the seal between the two circumferentially continuous deflector sections simultaneously achieves a circumferential seal between the two dome sections, thereby avoiding assembly errors.

[0019] The first sealing member may include a wall element applied from downstream to the circumferential ends of two circumferentially continuous deflector sections.

[0020] Designing the first sealing component as a wall element eliminates any doubt about the presence of the sealing components during endoscopic examination. This design also eliminates the risk of omitting sealing components during assembly and the risk of installing them in the wrong orientation. The shape of these components also ensures a mistake-proof design when they are installed between the two ring segments.

[0021] The second sealing member may include at least one first plate and a second plate that are disconnected from and connected to the first sealing member, the first plate and the second plate engaging in grooves at the edge of the first vault section, and the other engaging in a groove circumferentially toward the edge of a second circumferentially adjacent vault section.

[0022] It should be understood that the connection between the plate and the first component avoids the possibility of incorrect assembly of the plate when the plate and the first component are installed simultaneously between the two ring segments.

[0023] Each sealing component may include a first connecting element that connects the first plate to the wall element, the first connecting element being circumferentially inserted between two edges of a circumferentially adjacent deflector segment.

[0024] Each sealing component may include a second connecting element for connecting the second plate to the wall element, the second connecting element being circumferentially inserted between two edges of a circumferentially adjacent vault section.

[0025] These first and second connecting elements make it possible to impart robustness and strength to the sealing component. These first and second connecting elements also facilitate the assembly orientation of the sealing component.

[0026] These first and second connecting elements make it possible to mechanically hold the first sealing member to the second sealing member.

[0027] The second connecting element can be radially arranged outside the two edges of the circumferentially adjacent deflector section.

[0028] This document relates to a turbine turbine comprising a low-pressure turbine and a high-pressure turbine, the low-pressure turbine having an annular assembly including the features described above, the outer casing of the low-pressure turbine including an upstream annular flange for attachment to a downstream annular flange of the outer casing of the high-pressure turbine.

[0029] This article relates to a turbine that includes an annular assembly of the aforementioned type. Attached Figure Description

[0030] [ Figure 1 This is a partial schematic half-view showing a cross-section of the turbine module.

[0031] [ Figure 2 This image shows a partial schematic half-view of the axial cross-section of a turbine module according to the present invention;

[0032] [ Figure 3 [Demonstration of the invention] Figure 2 A schematic perspective view of the sealing ring section of the module;

[0033] [ Figure 4 A schematic perspective view showing two circumferentially continuous annular segments and a sealing component according to the present invention;

[0034] [ Figure 5 A schematic perspective view of a sealing member installed in a ring section, viewed from the side according to the present invention;

[0035] [ Figure 6 A schematic perspective view of a sealing component installed in a ring section, viewed from downstream according to the present invention;

[0036] [ Figure 7 A schematic perspective view of the in-situ fusion sealing component according to the present invention is shown. Detailed Implementation

[0037] The turbine comprises an upstream high-pressure turbine and a downstream low-pressure turbine. Each of the high-pressure and low-pressure turbines consists of alternating annular rows of stator blades and moving blades arranged within a casing. For example... Figure 2 As shown, the first downstream moving impeller 4 is externally surrounded by a low-pressure turbine housing 16a, while the upstream outlet distributor 2 of the high-pressure turbine is externally surrounded by a housing of the high-pressure turbine 16b. The distributor 2 has an outer annular platform 6 to which the radially outer ends of radial blades 8 are connected. A hook-and-loop tongue 32 is located at one end of the outer platform 6 of the distributor 2. The hook-and-loop tongue 32 ensures circumferential and axial retention of the distributor 2; it engages in an annular groove 33 of the high-pressure turbine housing 16b, which is open in the downstream direction.

[0038] The high-pressure turbine housing 16b is fixed at its downstream end to the annular flange 38 at the upstream end of the low-pressure turbine housing 16a by means of an annular flange 36. The annular flanges 36 and 38 are radially positioned in the annular space between the high-pressure outlet distributor 2 of the separating turbine and the first low-pressure moving wheel 4 of the turbine.

[0039] like Figure 2 As shown, the first movable impeller 4 is rotatably mounted about the longitudinal axis X in a ring attached to the outer housing 16a of the low-pressure turbine. The segmented ring is formed by a plurality of ring segments arranged circumferentially end-to-end and each supported by the outer housing 16a of the low-pressure turbine. The downstream end of each ring segment is radially clamped by a C-shaped clamping tab 22 located downstream of the ring segment.

[0040] like Figures 3 to 6As shown, each annular section includes a dome section 18 and an annular thermal deflector section 20 arranged radially outside the impeller 4.

[0041] The deflector section 20 is generally Z-shaped and has a generally curved orientation. From upstream to downstream, the deflector section 20 includes a radially inwardly extending wall section 40, an annular wall section 42, and a radially outwardly extending wall section 44. The radially outwardly extending wall section 44 is secured by welding to the downstream edge of the radial wall 46 of the vault section 18. The annular wall section 42 of the deflector section 20 circumferentially follows the extension direction of the vault section 18. The deflector section 20 has a circumferential extension that is generally equivalent to the circumferential extension of the vault section 18 and the wearable element 14, such that the circumferential ends of the deflector section 20 are generally axially aligned with the circumferential ends of the vault section 18 and the wearable element 14. This deflector section 20 may be an annular metal sheet section.

[0042] like Figures 2 to 6 As shown, the dome section 18 extends circumferentially and includes an annular wall section 48 supporting the wearable element 14 on its inner surface, and a radially inwardly extending wall section 46, which connects to a cylindrical wall section 50 that engages in an annular groove 34 carried by an annular flange 38 at the upstream end of the low-pressure turbine housing 16a. The wearable element 14 is honeycomb in form and seals the impeller 4 by means of an annular lug 12 extending radially outward from the outer annular platform 10 of the impeller 4, thereby restricting air from radially outward from the moving impeller 4. Typically, as Figure 4 As shown, sealing tongues 52 are inserted into longitudinal grooves in the longitudinal edges of the circumferential ends of the annular wall sections 48 of the vault section 18. Each of these sealing tongues 52 is inserted on a first side into a groove in the longitudinal edge of the circumferential end of the first vault section 18's annular wall section 48, and on a second side into a groove in the longitudinal edge of the circumferential end of the second circumferentially continuous vault section 18's annular wall section 48. These sealing tongues 52 are generally planar and elongated in shape.

[0043] like Figure 3 As shown, the radial edge of the circumferential end of the radial wall section 46 of the vault section 18 and the longitudinal edge of the circumferential end of the cylindrical wall section 48 of the vault section 18 have grooves 54, 55 for receiving sealing components.

[0044] like Figures 4 to 7 As shown, the sealing member 56 includes a first circumferential sealing member 58 between two circumferentially continuous deflector sections 20, specifically at the junction between the two circumferentially continuous deflector sections 20. It may also include a second sealing member 60 between two circumferentially continuous dome sections 18.

[0045] The first sealing member 58 includes a wall element 62, a downstream radial wall 64 extending outwardly and having its radially inner end connected to an inclined wall 66 converging toward the axis of rotation in the upstream direction, the inclined wall 66 being connected at its upstream end to an inwardly extending upstream radial wall 68.

[0046] The shape of this wall element 62 is the same as that of the thermal deflector section 20, so that it can perfectly match the three-dimensional form of the two circumferential edges of the deflector section 20.

[0047] The second sealing member 60 between two circumferentially continuous vault sections 18 includes a first plate 70 and a second plate 72 that are disconnected. These first plates 70 and 72 have a flat, generally rectangular shape. The first plate 70 is adapted to be inserted from a first side into a groove 54 at the edge of the circumferential end of the cylindrical wall section 50 of the first vault section 18, and from a second side opposite the first side into a groove 54 at the edge of the circumferential end of the cylindrical wall section 50 of the second circumferentially continuous vault section 18. The second plate 72 is insertable from the first side into a groove 55 at the radial edge of the circumferential end of the radial wall section 46 of the first vault section 18, and from the second side opposite the first side into a groove 55 at the radial edge of the circumferential end of the radial wall section of the second circumferentially continuous vault section 18.

[0048] The sealing member 56 includes a first connecting element 74 that connects the first plate 70 to an inclined wall 66 converging toward the axis of rotation in an upstream direction of the wall element wall 62. The first connecting element 74 extends radially in a generally frustoconical shape having a radially inwardly flared cross-section. This first connecting element 74 is attached to the wall element 62 at its radially inner end and to the inner surface of the first plate 70 at its radially outer end. The first connecting element 74 extends both radially and longitudinally.

[0049] The sealing component 56 also includes a second connecting element 76 connecting the second plate 72 to a downstream radial wall 64 extending radially outward from the wall element 62. The second connecting element extends longitudinally in a generally rectangular shape. This second connecting element 76 is attached to the wall element 62 at its radially inner end and to the inner surface of the second plate 72 at its radially outer end. The second connecting element 76 may extend radially from the inner end of the second plate 72 up to one-third of the radial length of the second plate 72.

[0050] The first connecting element 70 and the second connecting element 72 are planar and have a thickness between 0.2 and 0.4 mm. This thickness is on the same order of magnitude as the thickness of the first and second sealing members.

[0051] This sealing component 56 can be manufactured by additive manufacturing. The sealing component 56 is installed in a circumferential translational manner, with the radial outer surface of the wall element 62 matching the shape of the downstream face of the thermal deflector section 20, and the first 70 and second 72 plates inserted into the grooves 54, 55 of the housing of the two circumferentially continuous dome sections 18.

[0052] This article pays particular attention to the scenario in which it is used, namely at the junction between the high-pressure housing 16b and the low-pressure housing 16a, because this junction area of ​​the housing may be more sensitive to leaked hot air than any other area, due to the potential impact on fastening elements and the possibility that the differential thermal expansion between the two housings may lead to increased stress in the housing at its attachment point.

[0053] The sealing component 56 prevents combustion gases from passing through the circumferential and radial gaps between the two circumferentially continuous dome sections 18 and between the two continuous deflector sections 20.

[0054] The sealing component 56 makes it possible to block air in the gap between the disconnected first 70 and second 72 plates.

[0055] The engagement of the second sealing member 60 with the first sealing member 58 facilitates the assembly of the sealing component 56. The circumferential seal between the two dome sections 18 is thus performed simultaneously with the seal between the two circumferentially continuous deflector sections 20, thereby avoiding omissions or errors during assembly.

[0056] The design of the first sealing member 58 in the form of a wall element 62 eliminates any doubt about the presence of the sealing member 56 during endoscopic examination.

Claims

1. An annular assembly for a turbine turbine, the annular assembly extending about a longitudinal axis X and comprising: - Distributor (2), which is fixed to the outer housing (16); - Blade disk (4), which is arranged downstream of the distributor (2) and mounted to rotate inside the outer housing (16); - The blade disk (4) is surrounded by a circumferential segmented ring, which is supported by the outer housing (16). The circumferential segmented ring is formed by a segmented dome (18) arranged radially to the outside of the blade disk (4) and a segmented annular deflector (20). The segmented annular deflector is supported by the upstream edge of the segmented dome (18) and extends radially inward from the upstream edge of the segmented dome (18). The annular assembly is characterized in that it includes a sealing member (56) between two circumferentially adjacent annular segments, the sealing member (56) including a first circumferential sealing member (58) disposed at a junction between two circumferentially continuous segments of the segmented annular deflector (20), and the sealing member (56) including a second circumferential sealing member (60) between two circumferentially continuous segments of the segmented dome (18), the second circumferential sealing member (60) being connected to the first circumferential sealing member (58). The first circumferential sealing member (58) includes a wall element (62). The second circumferential sealing member (60) includes at least one first plate (70) and one second plate (72), the first plate and the second plate being disconnected from each other, and both the first plate and the second plate being connected to the first circumferential sealing member (58). A portion of the first plate (70) and the second plate (72) engage in grooves (54, 55) at the edge of the first arch section of the segmented arch (18), and another portion engages in grooves (54, 55) circumferentially facing the edge of the second circumferentially adjacent arch section of the segmented arch (18). Each of the sealing components (56) includes a first connecting element (74) that connects the first plate (70) to the wall element (62), the first connecting element (74) being circumferentially inserted between two edges of a circumferentially adjacent deflector segment of the segmented annular deflector (20).

2. The annular assembly according to claim 1, characterized in that, The wall element (62) is applied from downstream to the end opposite to the two circumferentially continuous deflector sections.

3. The annular assembly according to claim 1, characterized in that, Each sealing component (56) includes a second connecting element (76) that connects the second plate (72) to the wall element (62), the second connecting element (76) being circumferentially inserted between two edges of a circumferentially adjacent vault section.

4. The annular assembly according to claim 3, characterized in that, The second connecting element (76) is arranged radially outside the two edges of the circumferentially adjacent deflector section.

5. The annular assembly according to claim 1, characterized in that, The turbine mentioned is the turbine of the aircraft.

6. A turbine turbine comprising a low-pressure turbine and a high-pressure turbine, wherein the low-pressure turbine includes an annular assembly according to any of the preceding claims, and the outer housing (16a) of the low-pressure turbine includes an upstream annular flange (38) for attachment to a downstream annular flange (36) of the outer housing (16b) of the high-pressure turbine.

7. A turbine comprising an annular assembly according to any one of claims 1 to 5.

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