Turbomachines with heat shields

Abstract

The present invention relates to a turbomachinery (10). The turbomachinery (10) comprises a shaft (12) mounted on a bearing housing (11) on which a rotor (13) is disposed. The turbomachinery (10) further comprises a heat shield (14) disposed between the bearing housing (11) and the gas outlet housing (15) of the turbomachinery. The heat shield (14) has radially outward fastening element receiving portions (141) for fastening the heat shield (14) to the bearing housing (11) by fastening elements (16). The fastening element receiving portions (141) are disposed between the bearing housing (11) and the gas outlet housing (15). The fastening element receiving portions (141) are axial fastening element receiving portions. The fastening elements (16) extend through the axial fastening element receiving portions.

Description

[Technical Field]

[0001] The present invention relates to turbomachinery, and more particularly to exhaust gas turbines. More specifically, the present invention relates to turbomachinery equipped with a heat shield. [Background technology]

[0002] Today, to improve the performance of internal combustion engines, it is common to use exhaust gas turbochargers, which consist of a turbine in the exhaust pipe of the internal combustion engine and a compressor upstream of the engine. The exhaust gases from the internal combustion engine are expanded by the turbine. The work obtained in this process is transmitted by a shaft to the compressor, which compresses the air supplied to the internal combustion engine. By using the energy from the exhaust gases to compress the air supplied for the combustion process of the internal combustion engine, the efficiency of the combustion process and the internal combustion engine can be optimized.

[0003] In turbomachinery, specifically exhaust gas turbochargers, a device called a heat shield is commonly used. The main purpose of the heat shield is to reduce the heat input from the turbine side to the bearing housing. There are basically two different types of heat shield designs. On the one hand, the heat shield is constructed as a solid, machined and partially cast structural member, while on the other hand, designs made from sheet metal formed parts are also used. Typically, both types are clamped around the periphery.

[0004] It is known that conventional thermal shields can be further improved, specifically in terms of their fastening and thermal insulation efficiency, and more specifically in the fastening region of the thermal shield. [Overview of the project] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a turbomachine equipped with a heat shield that can partially or completely overcome one or more of the drawbacks known from the prior art. [Means for solving the problem]

[0006] To achieve the above-mentioned objectives, a turbomachine equipped with a heat shield as described in the independent claim is provided. Further aspects, advantages, and features of the present invention can be found in the dependent claims, specification, and accompanying drawings.

[0007] According to one aspect of the present invention, a turbomachinery, more particularly an exhaust gas turbine, is provided. The turbomachinery comprises a shaft mounted on a bearing housing, on which a rotor is disposed. Furthermore, the turbomachinery comprises a heat shield disposed between the bearing housing and the gas outlet housing of the turbomachinery. The heat shield has radially outward fastener receivers for fastening the heat shield to the bearing housing by fasteners. The fastener receivers are located between the bearing housing and the gas outlet housing, and the fastener receivers are axial fastener receivers. The fasteners extend through the axial fastener receivers.

[0008] Accordingly, a turbomachine with a heat shield is advantageously provided, which is improved in that it reduces the heat input from the turbine side to the bearing housing compared to turbomachines with heat shields known from the prior art. In particular, embodiments described herein advantageously enable a reduction in heat transfer or movement between the gas outlet housing and the fastening portion of the heat shield.

[0009] The present invention will be described below with reference to exemplary embodiments shown in the drawings, from which further advantages and modifications can be derived. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic cross-sectional view of a turbomachinery equipped with a heat shield according to an embodiment described herein. [Figure 2] This is a schematic cross-sectional view showing details of a turbomachine equipped with a heat shield fastening according to an embodiment described herein. [Figure 3] A schematic cross-sectional view showing details of a turbomachine with a heat shield fastening part according to a further embodiment described herein, which has a cooling structure.

Mode for Carrying Out the Invention

[0011] Various embodiments in which one or more examples are shown in each figure will be described below. Each example is useful for explanation and should not be construed in a limiting sense. For example, features shown or described as part of one embodiment can be used on or in combination with other embodiments to obtain another embodiment. The present disclosure intends to include such modifications and variations.

[0012] In the following description of the drawings, the same reference numerals refer to the same or similar components. Generally, only the differences regarding individual embodiments are described. Unless otherwise specified, the description of a component or aspect in one embodiment may also be relevant to the corresponding component or corresponding aspect in another embodiment.

[0013] Referring to FIGS. 1 and 2, a turbomachine 10 according to an embodiment of the present disclosure will be described. Specifically, the turbomachine 10 can be an exhaust gas turbine. For example, the exhaust gas turbine can be an axial flow exhaust gas turbine. The exhaust gas turbine can be part of an exhaust gas turbocharger. Further, in the drawings, note that the axial direction x and the radial direction r referred to below are illustratively shown.

[0014] According to one embodiment, which can be combined with other embodiments described herein, the turbomachine 10 comprises a shaft 12 mounted on a bearing housing 11, on which a rotor 13 is disposed. The bearing housing can be understood as a structural component of the turbomachine that serves to house and protect bearings for supporting the shaft coupled to the rotor. The rotor may be, for example, a turbine wheel. More specifically, the rotor may be a turbine disk. A turbine disk typically comprises vanes or blades mounted on a disc-shaped structure. In addition, the turbomachine 10 comprises a heat shield 14 located between the bearing housing 11 and the gas outlet housing 15 of the turbomachine.

[0015] A heat shield can be understood as a structural component that plays a role in dissipating thermal energy from a high-temperature source and protecting surrounding components from excessive heat. In the context of turbomachinery, heat shields are typically positioned to ensure the thermal insulation and protection from high temperatures of the bearing housing. Typically, a heat shield is a single structural member. In other words, a heat shield is typically provided by a single, continuous, undivided structural member. Typically, a heat shield has a rotationally symmetric design and features a central opening for the shaft to pass through.

[0016] As exemplarily shown in FIG. 1, the heat shield 14 has one or more radially outer fastener receiving portions 141 for fastening the heat shield 14 to the bearing housing 11 by one or more fasteners (plural possible) 16. The fastener can be, for example, a screw, a bolt, a pin, a rivet, or other suitable fastener. Preferably, the fastener is a releasable one such as a screw. Specifically, the fastener described in this specification can be a screw, and its length is selected so as to ensure the self-locking of the screw. Typically, the length of the screw, specifically, for example, with respect to preventing the unintentional loosening of the screw due to vibration, load or other external influences, affects the self-locking characteristics. A relatively long screw results in a large contact area between the screw and the material to be screwed. Thereby, the frictional force for holding the screw in place increases, and the possibility of the screw loosening due to vibration or load is reduced. Also, a relatively long screw can contribute to the improvement of the stress distribution at the fastening location. With a relatively long screw, the load is dispersed over a relatively wide area, thereby relieving the load concentration and increasing the strength of the connection part.

[0017] The radially outer fastener receiving portion 141 of the heat shield 14 can be understood as a fastener receiving portion arranged at a position closer to the outer edge of the heat shield than the center of the heat shield in the radial direction. The radially outer region of the heat shield where the fastener receiving portion 141 described in this specification is arranged is typically provided so as to extend over a radial region r of 0.6×R≦r≦R, specifically 0.7×R≦r≦R, specifically 0.8×R≦r≦R, where R is the radius of the heat shield.

[0018] One or more fastener receiving portions 141 are located between the bearing housing 11 and the gas outlet housing 15. More specifically, one or more fastener receiving portions 141 and corresponding fasteners(s) 16 are located between the bearing housing 11 and the gas outlet housing 15. In other words, typically, no components other than fastener receiving portions and corresponding fasteners are located in the fastening region of the heat shield 14 between the bearing housing 11 and the gas outlet housing 15. Note that typically, multiple fastener receiving portions 141 are provided circumferentially to fasten the heat shield 14 to the bearing housing 11 with multiple fasteners 16. More specifically, the heat shield may have two, three, four, five, or more fastener receiving portions 141.

[0019] According to one embodiment, which can be combined with other embodiments described herein, a first air-filled insulating chamber 17 is provided between the fastener receiving portion 141 and the gas outlet housing 15. In this disclosure, the air-filled insulating chamber can be understood as a cavity or chamber that is filled with air and serves to create an insulating barrier. The first air-filled insulating chamber 17 typically serves to create an insulating barrier between the gas outlet housing 15 and the fastener receiving portion 141. This can advantageously reduce heat transfer or movement between the gas outlet housing and the fastener receiving portion.

[0020] In other words, the air-filled insulated chamber can function as a kind of buffer zone or intermediate chamber that absorbs, disperses, and reduces the thermal energy carried by the gas in the gas outlet housing. By using air as the insulating medium, the insulated chamber can lower the temperature of the fastening portion of the heat shield and thus contribute to reducing the thermal load on the fastener receiver and the surrounding bearing housing.

[0021] According to one embodiment that can be combined with other embodiments described in this specification, as exemplarily shown in FIG. 1, a second air-filled adiabatic chamber 18 is provided between the radially outer region 144 of the thermal shield 14 and the bearing housing 11.

[0022] Typically, the first air-filled adiabatic chamber 17 extends in the radial direction r between R 1min and R 1max (R 1min ≦r≦R 1max ). Specifically, the first air-filled adiabatic chamber 17 is a chamber that extends circumferentially around the rotational center axis 121 of the shaft 12. For example, the first air-filled adiabatic chamber 17 can be a rotationally symmetric chamber.

[0023] Typically, the second air-filled adiabatic chamber 18 extends in the radial direction r between R 2min and R 2max (R 2min ≦r≦R 2max ). Specifically, the second air-filled adiabatic chamber 18 is a chamber that extends circumferentially around the rotational center axis 121 of the shaft 12. For example, the second air-filled adiabatic chamber 18 can be a rotationally symmetric chamber.

[0024] Typically, the maximum radial dimension R 2max of the second air-filled adiabatic chamber 18 from the rotational center axis 121 of the shaft 12 is smaller than the maximum radial dimension R 1max of the first air-filled adiabatic chamber 17 (R 2max <R 1max ).

[0025] Furthermore, the minimum radial dimension R 2min of the second air-filled adiabatic chamber 18 from the rotational center axis 121 of the shaft 12 is typically smaller than the minimum radial dimension R 1min of the first air-filled adiabatic chamber 17 (R 2min <R 1min ).

[0026] In addition, as exemplarily shown in FIG. 1, R 1min may be smaller than R 2max (R1min <R 2max ). Or, R 1min R 2max It may be larger than (R 1min >R 2max (Not explicitly illustrated).

[0027] As illustrated in Figure 1, a heat shield 14 according to one embodiment, which can be combined with other embodiments described herein, provides a side wall 21 on the bearing housing side of the gas outlet passage 20 of the turbomachinery.

[0028] According to one embodiment, which can be combined with other embodiments described herein, a third air-filled insulated chamber 19 is provided between the bearing housing-side side wall 21 of the gas outlet passage 20 and the bearing housing 11. Typically, the third air-filled insulated chamber 19 extends along the bearing housing-side rear surface of the bearing housing-side side wall 21 of the gas outlet passage 20. Typically, the third air-filled insulated chamber 19 is a chamber that extends circumferentially around the rotational axis 121 of the shaft 12. For example, the third air-filled insulated chamber 19 can be a rotationally symmetric chamber.

[0029] According to one embodiment, which can be combined with other embodiments described herein, the bearing housing 11 includes an oil chamber 111. The oil chamber is typically thermally shielded by a heat shield described herein to avoid oil coking. For example, the oil chamber may be an emergency oil tank integrated into the bearing housing.

[0030] The fastener receiving portion 141 typically contacts the bearing housing 11 in the radially outer region 112 of the bearing housing 11. The fastener receiving portion 141 can contact the bearing housing 11 in the region of the bearing housing where the oil chamber 111 is located. Alternatively, the fastener receiving portion 141 can contact the bearing housing 11 in the region of the bearing housing where the oil chamber 111 is only partially located. According to a further alternative, the fastener receiving portion 141 can contact the bearing housing 11 in the region of the bearing housing where the oil chamber 111 is not located. More specifically, the fastener receiving portion 141 can contact the bearing housing 11 in the region of the bearing housing where it is located radially outward from the oil chamber 111.

[0031] According to one embodiment that can be combined with other embodiments described herein, as illustrated in Figure 3, one or more fasteners 16 by which the heat shield 14 is fastened to the bearing housing may extend into one or more cooling structures 117. For example, one or more cooling structures 117 may be located within the oil chamber 111 of the bearing housing 11. This advantageously allows heat input from the turbine side to be dissipated in a controlled manner into the bearing housing, and more specifically into the cooling structures.

[0032] According to one embodiment that can be combined with other embodiments described herein, one or more cooling structures 117 located within the oil chamber 111 of the bearing housing 11 are webs. For example, one or more cooling structures 117 can be axial webs. In other words, one or more cooling structures typically extend substantially axially into the oil chamber 111. "Substantially axial" is understood as a direction having an angular tolerance T of T ≤ ±20 degrees, more specifically T ≤ ±10 degrees, from the axial direction. As illustrated in Figure 1, the axial direction x typically extends along the axis of rotation 121 of the shaft 12 in which the rotor 13 is located.

[0033] According to one embodiment that can be combined with other embodiments described herein, one or more cooling structures 117 are coupled to the turbine-side bearing housing wall 114, as illustrated in Figure 3. More specifically, one or more cooling structures 117 can be formed integrally with the turbine-side bearing housing wall 114. Typically, one or more fasteners 16 extend through the turbine-side bearing housing wall 114 in a non-contact manner. In other words, as illustrated in Figure 3, one or more fasteners 16 can be surrounded by an air casing 118 in the region of the turbine-side bearing housing wall 114.

[0034] According to one embodiment that can be combined with other embodiments described herein, as illustrated in Figure 3, the turbine-side bearing housing wall 114 has one or more threadless fastener receiving portions 115, and one or more fasteners 16 extend through these fastener receiving portions 115 in a non-contact manner. The one or more threadless fastener receiving portions 115 can be designed, for example, to provide the air casing 118 described above.

[0035] Typically, one or more threadless fastener receivers 115 extend substantially axially. For example, one or more threadless fastener receivers 115 may have one or more bores, and one or more fasteners 16 may extend through these bores in a non-contact manner. In addition, one or more fastener receivers 115 may have turbine-side recesses 116, as illustrated in Figure 3, for example. For example, the turbine-side recesses 116 of one or more fastener receivers 115 may be designed as counterbore or countersunk recesses. These recesses reduce contact between the fasteners and the bearing housing, which has a favorable effect in reducing heat input to the bearing housing.

[0036] According to one embodiment that can be combined with other embodiments described herein, the fastener 16 extending into the cooling structure described herein is a screw that engages with a female thread provided within the cooling structure. Typically, the female thread is provided only within the cooling structure. Furthermore, the male thread of the screw extending into the cooling structure described herein is provided only in the front end region of the screw, and this front end region engages with the female thread of the cooling structure.

[0037] It should be noted that, in the fastening configuration described herein, in particular, the fastener extends through the turbine-side bearing housing wall in a non-contact manner, and the threads are located in the region of the cooling structure, thereby enabling controlled heat dissipation from the turbine side into the bearing housing. Furthermore, the length of the threads can be advantageously selected to ensure self-locking of the threads. Furthermore, it should be noted that, with respect to the fastener receiving portion 115 and / or recess 116 and / or air casing 118 without one or more threads, the features described in relation to the embodiment shown in Figure 3 can be moved to the embodiments shown in Figures 1 and 2.

[0038] According to one embodiment that can be combined with other embodiments described herein, a radial gap S exists between the fastener receiving portion 141 and the gas outlet housing 15. Typically, the radial gap S is filled with air and acts as a heat transfer barrier, which has a favorable effect in reducing the heat input to the fastener receiving portion 141.

[0039] According to one embodiment that can be combined with other embodiments described herein, the fastener receiver 141 is an axial fastener receiver. The axial fastener receiver can be understood as a receiver that serves to receive fasteners in the axial direction x.

[0040] According to one embodiment which can be combined with other embodiments described herein, the bearing housing 11 has a seat 113, more specifically a radial seat, for a complementary seat 142 of the heat shield 14.

[0041] In this disclosure, the terms “seat” and “complementary seat” refer to two matching surfaces or structures that cooperate to enable stable and accurate positioning or mating of the heat shield 14 onto the bearing housing 11.

[0042] Typically, the term “seat” refers to a structural means or recess within the bearing housing 11 that contributes to fastening or positioning the heat shield 14. The seat 113 can be realized, for example, by a stepped portion in the radial direction r, as illustrated in Figure 2. Furthermore, the seat typically comprises a circumferential surface 113U extending in the axial direction. The radial position of the seat is, for example, the minimum radial dimension R of the second air-filled insulated chamber, as illustrated in Figure 1. 2min It can correspond to the radial position.

[0043] The complementary seat 142 refers to a corresponding surface or structure of the heat shield 14, which fits precisely onto or onto the seat 113 of the bearing housing 11. The complementary seat is configured to ensure that the bearing housing and the heat shield are precisely fitted and coupled together. In other words, the seat 113 and the complementary seat 142 are typically configured, from a geometric standpoint, to precisely orient and position the heat shield within the bearing housing.

[0044] According to one embodiment, which can be combined with other embodiments described herein, a complementary seat portion 142 of the heat shield 14 is coupled to a fastener receiving portion 141 via a substantially radially extending web 143. Typically, the web 143 forms part of the wall of a first air-filled insulated chamber 17. Furthermore, the web 143 may also form part of the wall of a second air-filled insulated chamber 18. In detail, as illustrated in Figure 2, the web can be positioned between the first air-filled insulated chamber 17 and the second air-filled insulated chamber 18.

[0045] According to one embodiment, which can be combined with other embodiments described herein, a seal 151, more specifically a labyrinth seal, is provided at the interface between the gas outlet housing 15 and the heat shield 14. As illustrated in Figure 2, the use of a seal, more specifically a labyrinth seal, at the interface between the gas outlet housing and the heat shield is advantageous in that it contributes to heat insulation between the gas outlet housing and the fastener receiving portion of the heat shield.

[0046] As will be apparent from the embodiments described herein, turbomachinery with improved fastenings for the heat shield is advantageously provided, offering improved thermal insulation properties of the heat shield, and more specifically, thermal insulation properties in the area of ​​the fastening, compared to the prior art. [Explanation of symbols]

[0047] 10 Turbomachinery 11. Bearing housing 111 Oil chamber 112 Radial outer region of the bearing housing 113 Seat area 113U Circumferential surface of the seat 114 Turbine-side bearing housing wall 115 Fastener receiver without threads 116 Turbine-side recess 117 Cooling structure 118 Air Casing 12 shafts 121 Rotational center axis 13 Rotors 14 Heat Shield 141 Fastener receiving section 142 Complementary seating area of ​​the heat shield 143 Web 144 Radial outer region of the heat shield 15 Gas outlet housing 151 Seals 16 Fasteners 17. The first air-filled insulated chamber 18. Second air-filled insulated chamber 19. Third air-filled insulated chamber 20 Gas outlet passage x-axis direction r radial direction S Radial gap R: Radius of the heat shield R 1min Minimum radial dimensions of the first air-filled insulated chamber R 1max Maximum radial dimensions of the first air-filled insulated chamber R 2min Minimum radial dimensions of the second air-filled insulated chamber R 2max Maximum radial dimensions of the second air-filled insulated chamber

Claims

1. A turbomachinery (10), A shaft (12) is mounted inside a bearing housing (11), with a rotor (13) positioned on top of it, A heat shield (14) is positioned between the bearing housing (11) and the gas outlet housing (15) of the turbomachinery, Equipped with, The heat shield (14) has a radially outward fastener receiving portion (141) for fastening the heat shield (14) to the bearing housing (11) by a fastener (16), the fastener receiving portion (141) is positioned between the bearing housing (11) and the gas outlet housing (15), the fastener receiving portion (141) is an axial fastener receiving portion, and the fastener (16) extends through the axial fastener receiving portion, the turbomachinery (10).

2. The turbomachine (10) according to claim 1, wherein a first air-filled insulated chamber (17) is provided between the fastener receiving portion (141) and the gas outlet housing (15).

3. The turbomachinery (10) according to claim 1 or 2, wherein a second air-filled insulated chamber (18) is provided between the radially outer region (144) of the heat shield (14) and the bearing housing (11).

4. The maximum radial dimension R of the second air-filled insulated chamber (18) from the rotational axis (121) of the shaft (12). 2max However, the maximum radial dimension R of the first air-filled insulated chamber (17) 1max A turbomachinery (10) according to claim 3, which is smaller than the turbomachinery (10).

5. The turbomachinery (10) according to any one of claims 1 to 4, wherein the heat shield (14) provides a side wall (21) on the bearing housing side of the gas outlet passage (20) of the turbomachinery.

6. The turbomachinery (10) according to claim 5, wherein a third air-filled insulated chamber (19) is provided between the side wall (21) of the gas outlet passage (20) on the bearing housing side and the bearing housing (11).

7. The turbomachinery (10) according to any one of claims 1 to 6, wherein the bearing housing (11) comprises an oil chamber (111), and the fastener receiving portion (141) contacts the bearing housing (11) in a radially outer region (112) of the bearing housing (11) to which the oil chamber extends fully.

8. The turbomachinery (10) according to any one of claims 1 to 6, wherein the bearing housing (11) comprises an oil chamber (111), and the fastener receiving portion (141) contacts the bearing housing (11) in a radially outer region (112) of the bearing housing (11) where the oil chamber does not extend or extends only partially.

9. The turbomachinery (10) according to any one of claims 1 to 8, wherein the fastener 16 extends into a cooling structure 117 located within the oil chamber 111 of the bearing housing 11.

10. The turbomachinery (10) according to any one of claims 1 to 9, wherein there is a radial gap (S) between the fastener receiving portion (141) and the gas outlet housing (15).

11. The turbomachinery (10) according to any one of claims 1 to 10, wherein the bearing housing (11) has a seat (113), more specifically a radial seat, for a complementary seat (142) of the heat shield (14).

12. The turbomachinery (10) according to claim 11, wherein the complementary seat portion (142) of the heat shield (14) is coupled to the fastener receiving portion (141) via a substantially radially extending web (143).

13. A seal (151), more specifically a labyrinth seal, is provided at the interface between the gas outlet housing (15) and the heat shield (14) in the turbomachinery (10) according to any one of claims 1 to 12.

14. The turbomachinery (10) according to any one of claims 1 to 13, wherein the turbomachinery is an axial flow exhaust gas turbine, and the rotor (13) is a turbine wheel, more specifically a turbine disc.

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