Compressor housing, centrifugal compressor having such compressor housing, centrifugal compressor assembly, exhaust gas turbocharger and internal combustion engine
By installing the fluid technology connection and valve device in the compressor housing of the centrifugal compressor, the flow cross-section is changed, the problem of compressor surge is solved, and stable and power-optimized motor operation is achieved.
Patent Information
- Application Number
- CN202380059595.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-08-17
- Filing Date
- 2023-08-03
- Publication Date
- 2025-03-25
AI Technical Summary
The reduced mass flow of fluid in the diffuser of existing centrifugal compressors may lead to flow instability and return flow, resulting in compressor surge, affecting the stable operation of the internal combustion engine.
A compressor housing for centrifugal compressor is designed, including accommodating space, flow-through area and collection cavity, and a fluid technology connection and valve device are provided between the collection cavity and flow-through area, so as to stabilize and move the characteristic curve of the compressor by changing the flow cross-section of the fluid connection to avoid compressor surge.
Through variable recirculation and recirculation in the flow-off area, the characteristic curve of the compressor is significantly improved, and stable and power-optimized motor operation is achieved, avoiding power loss caused by compressor surge.
Smart Images
Figure CN119698524A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a compressor housing, a centrifugal compressor having such a compressor housing, a centrifugal compressor assembly having such a centrifugal compressor, an exhaust gas turbocharger having such a centrifugal compressor assembly or such a centrifugal compressor, and an internal combustion engine having such an exhaust gas turbocharger, such a centrifugal compressor assembly or such a centrifugal compressor. Background Art
[0002] Centrifugal compressors of the type discussed here typically have a diffuser in which the flow velocity of the compressed fluid is reduced in order to facilitate the pressure buildup. If the mass flow of the fluid in the diffuser is reduced, flow instabilities and / or backflows can occur, since the available flow channels are not fully utilized and the pressure gradient of the fluid acts opposite to its flow direction. In such operating conditions, compressor surges of the centrifugal compressor can occur, wherein in particular stable motor operation of the internal combustion engine with the centrifugal compressor cannot be achieved; in particular, certain operating ranges of the internal combustion engine are not movable and it is possible that the target for operating the internal combustion engine cannot be presented. Compressor surges can in particular have the result that the power of the internal combustion engine has to be reduced.
[0003] Basically, it is feasible that the characteristic curve of the centrifugal compressor is stabilized or shifted by measures such as recirculating the delivered fluid. Thus, however, further disadvantages may occur, especially depending on the specific design, especially in the characteristic curve region where there is actually no need to worry about compressor surge. Summary of the invention
[0004] The present invention is therefore based on the object of providing a compressor housing, a centrifugal compressor having such a compressor housing, a centrifugal compressor assembly having such a centrifugal compressor, an exhaust gas turbocharger having such a centrifugal compressor assembly or such a centrifugal compressor, and an internal combustion engine having such an exhaust gas turbocharger, such a centrifugal compressor assembly or such a centrifugal compressor, in which the mentioned disadvantages are at least reduced and preferably no longer occur.
[0005] This object is achieved by providing the present technical teaching, in particular the teaching of the independent claim and the teaching of the preferred embodiments disclosed in the dependent claims and the description.
[0006] The object is achieved in particular by providing a compressor housing for a centrifugal compressor, which has a receiving space for a compressor wheel, a flow-off region and a collecting cavity, wherein the compressor housing further has a fluidic connection between the collecting cavity and the flow-off region, in particular a fluidic return connection, and a valve device. The valve device is arranged and set up to change the flow cross section of the fluidic connection between the collecting cavity and the flow-off region. By means of the fluidic connection between the collecting cavity and the flow-off region, the characteristic curve of the centrifugal compressor with the compressor housing can be advantageously widened, shifted and / or stabilized, in particular to avoid compressor surge. By means of the valve device, it is advantageously possible that a corresponding change of the characteristic curve is only carried out when compressor surge should actually be feared and / or only when compressor surge should actually be feared. Conversely, if the centrifugal compressor is operated in a characteristic curve region in which compressor surge does not occur, the flow cross section of the fluidic connection can be reduced, in particular to zero, so that at least substantially, preferably completely, the characteristic curve that would be obtained without the fluidic connection is obtained. As a result, the following disadvantages can be reduced or avoided, especially in such an operating range, which in other cases would be associated with a change in the characteristic curve, especially efficiency losses. Recirculation, in particular, basically leads to efficiency losses and a drop in the compression ratio above the centrifugal compressor, but this is accepted in the characteristic curve region where compressor surge is about to occur, especially in order to facilitate stable motor operation without power losses. Now, the feasible scheme of disconnecting the recirculation advantageously avoids power losses in the following characteristic curve region of the centrifugal compressor, in which no compressor surge is about to occur, and thus no other advantages are opposed to power losses, especially in the case of the rated power of the internal combustion engine. Recirculation into the flow-away region advantageously achieves a further improvement of the surge limit. As a result, in particular, the combination of a variable, especially switchable and disconnectable recirculation on the one hand and a recirculation in the flow-away region downstream of the compressor wheel on the other hand achieves a significantly improved characteristic curve and a stable, power-optimized motor operation.
[0007] The fluidic connection between the collecting cavity and the flow-away region is particularly designed so that, when a centrifugal compressor having a compressor housing is in operation, a gas flow can flow from the collecting cavity into the flow-away region, particularly opposite to the main flow direction in the centrifugal compressor. The fluidic connection is particularly a second fluidic connection between the collecting cavity and the flow-away region, which is formed in addition to a first fluidic connection formed between the flow-away region and the collecting cavity along the main flow direction. Therefore, the second fluidic connection is also particularly referred to as a fluidic return connection.
[0008] The flow-off region is arranged in particular downstream of the compressor wheel.
[0009] The flow-off region has, in particular, at least one fixed guide blade, in particular a plurality of fixed guide blades.
[0010] The collecting cavity is arranged in particular downstream of the compressor wheel, in particular downstream of the flow-off region. Alternatively or additionally, the collecting cavity is part of a diffuser section of the compressor housing.
[0011] In one configuration, the compressor housing has a diffuser section which comprises, in particular, a flow-off region and a collecting cavity or is formed by the flow-off region and the collecting cavity.
[0012] The valve device is designed in particular to vary the flow cross section of the fluidic connection between the collecting cavity and the flow-off region in a parameter-dependent manner, ie in a parameter-dependent manner.
[0013] The valve device is designed in particular to selectively interrupt or open the fluidic connection, in particular depending on parameters.
[0014] The valve device is designed in particular to completely open or completely close the fluidic connection, in particular depending on a parameter, or to open the fluidic connection gradually, in particular in discrete steps or continuously, in particular depending on a parameter.
[0015] According to a further development of the invention, it is provided that the compressor housing has a first housing wall which delimits the receiving space, the flow-off region and the collecting cavity at least partially, wherein at least one outflow opening into the collecting cavity and at least one inflow opening into the flow-off region are formed in the first housing wall, wherein the collecting cavity is fluidically connected to the flow-off region via the at least one outflow opening and the at least one inflow opening. This results in a design of the compressor housing which is not only compact but also simple and cost-effective to manufacture.
[0016] In one embodiment, the first housing wall can be constructed in multiple parts. In another embodiment, the first housing wall is constructed in one piece, in particular of a uniform material. In one embodiment, the first housing wall can be constructed in particular as a cast part or as part of a cast part.
[0017] The fluidic connection between the collecting cavity and the flow-off region is established or constructed in particular by at least one outflow opening and at least one inflow opening. The at least one outflow opening is in particular fluidically connected to the at least one inflow opening so that during operation of a centrifugal compressor having a compressor housing, a gas flow can flow from the collecting cavity through the at least one outflow opening and the at least one inflow opening into the flow-off region.
[0018] According to a further development of the invention, it is provided that the compressor housing has an annular space into which, on the one hand, at least one outflow opening and, on the other hand, at least one inflow opening opens, so that the collecting cavity is fluidically connected to the flow-off region via the annular space. This results in a particularly compact design of the compressor housing.
[0019] The annular space surrounds the accommodation space concentrically, in particular in the peripheral direction. In one embodiment, the annular space is a protective space or containment space provided to stabilize the compressor housing or to protect people standing nearby or adjacent equipment, in particular, in the event of a compressor wheel being destroyed (in particular due to cracking).
[0020] In the context of current technical teachings, an axial direction is understood to be a direction which, when the compressor wheel is arranged in a compressor housing, in particular in a receiving space, runs along an imaginary axis of rotation of the compressor wheel. A peripheral direction concentrically surrounds the axial direction. A radial direction is perpendicular to the axial direction.
[0021] According to a further development of the invention, it is provided that the compressor housing has a second housing wall which connects the collecting cavity wall section of the first housing wall to the flow-off region wall section of the first housing wall. This represents a particularly simple design in order to mechanically stabilize the compressor housing and to form the annular space.
[0022] In particular, the annular space is bounded, in particular completely bounded, on the one hand by the first housing wall and on the other hand by the second housing wall.
[0023] In one embodiment, the second housing wall can be constructed in multiple parts. In another embodiment, the second housing wall is constructed in one piece, in particular of a uniform material. In one embodiment, the second housing wall can be constructed in one piece, in particular of a uniform material with the first housing wall. In one embodiment, the compressor housing can be constructed in particular as a cast part with the first housing wall and the second housing wall.
[0024] According to a further development of the invention, the valve device is designed to selectively open and close at least one opening selected from the outflow opening and the inflow opening. This represents a particularly simple and compact possibility for changing the flow cross section of the fluidic connection.
[0025] According to a refinement of the invention, the first housing wall has a plurality of inflow holes that open into the flow-off region. In this way, a portion of the fluid from the collecting cavity can be recirculated into the flow-off region very effectively to change the compressor characteristic curve.
[0026] The inflow openings are arranged in particular distributed along the circumference, ie in particular along the circumferential direction, at equal angular spacings. This allows a part of the compressed fluid to be recirculated particularly uniformly and effectively.
[0027] Alternatively or additionally, it is possible that the first housing wall has a plurality of outflow openings which open into the collecting space and in particular into the annular space. The outflow openings are arranged distributed in particular along the circumference, that is to say in particular in the circumferential direction, at equal angular spacings.
[0028] The valve device is designed in particular to selectively open or close all outflow openings and / or all inflow openings, in particular simultaneously.
[0029] According to a further development of the invention, it is provided that at least one inlet opening is designed in the form of a nozzle. This allows the recirculated fluid to flow into the outflow region in a directed and thus particularly efficient manner.
[0030] In one embodiment, at least one nozzle-shaped inflow opening has an insert, in particular a nozzle insert, which is integrated or inserted into the first housing wall, or is configured as such an insert. In another embodiment, at least one nozzle-shaped inflow opening is molded or formed by the first housing wall.
[0031] The object is also achieved by providing a centrifugal compressor having a compressor housing according to the invention or a compressor housing according to one or more of the previously described embodiments. In conjunction with the centrifugal compressor, in particular the advantages already explained above in conjunction with the compressor housing result.
[0032] According to a development of the invention, it is provided that a compressor wheel is arranged in the receiving space.
[0033] The compressor wheel has, in particular, at least one rotating guide blade, in particular a plurality of rotating guide blades.
[0034] The object is also achieved by providing a centrifugal compressor assembly having a centrifugal compressor according to the invention or according to one or more of the previously described embodiments, and having a control device which is operatively connected to the valve device and is designed to actuate the valve device. In conjunction with the centrifugal compressor assembly, the advantages already explained above in conjunction with the compressor housing or the centrifugal compressor are obtained in particular.
[0035] The control device is particularly designed to actuate the valve device as a function of a parameter, that is to say as a function of at least one parameter. In this way, a very flexible change of the characteristic curve of the centrifugal compressor can be performed, wherein the characteristic curve can in particular remain unchanged when the centrifugal compressor is operated in a characteristic curve region in which compressor surge is not to be feared.
[0036] According to a further development of the invention, it is provided that the control device is designed to control the valve device into the open position when the operating state of the centrifugal compressor is in a predetermined characteristic curve region arranged adjacent to the surge limit. In particular, in such a characteristic curve region there is a risk of compressor surge, so it is advantageous to control the valve device into the open position in order to open the fluidic connection.
[0037] In one embodiment, the control device is designed to actuate the valve device as a function of at least one parameter such that the fluidic connection is optionally completely opened or completely closed or is opened gradually, in particular in discrete steps or continuously.
[0038] The at least one parameter is selected in particular from the group consisting of: a pressure downstream of the centrifugal compressor, a pressure loss across the centrifugal compressor, a rotational speed of the compressor wheel, and a mass flow through the centrifugal compressor. The parameter in particular extends a characteristic curve of the centrifugal compressor and is therefore suitable for assessing the risk of compressor surge and, if necessary, initiating corresponding countermeasures.
[0039] In one specific embodiment, the control device is designed to open or close the fluidic connection as a function of a comparison of the at least one parameter with an associated limiting value.
[0040] The control device is in particular operatively connected to at least one parameter sensor which is arranged and configured to detect at least one parameter. The at least one parameter sensor is in particular selected from the group consisting of a pressure sensor, a rotational speed meter and a mass flow sensor.
[0041] Alternatively or additionally, it is possible that the control device is designed to calculate or determine the at least one parameter by simulation or to obtain the at least one parameter from another computing device, for example a control unit of the internal combustion engine.
[0042] The object is also achieved by providing an exhaust gas turbocharger having a centrifugal compressor according to the invention or according to one or more of the previously described embodiments, or having a centrifugal compressor assembly according to the invention or according to one or more of the previously described embodiments. In conjunction with the exhaust gas turbocharger, in particular, the advantages already explained above in conjunction with the centrifugal compressor assembly, the centrifugal compressor or the compressor housing result.
[0043] Finally, the object is also achieved by providing an internal combustion engine having a centrifugal compressor according to the invention or a centrifugal compressor according to one or more of the previously described embodiments, or having a centrifugal compressor assembly according to the invention or a centrifugal compressor assembly according to one or more of the previously described embodiments, or having an exhaust gas turbocharger according to the invention or an exhaust gas turbocharger according to one or more of the previously described embodiments. In conjunction with the internal combustion engine, in particular, the advantages already explained above in conjunction with the compressor housing, the centrifugal compressor, the centrifugal compressor assembly or the exhaust gas turbocharger result. BRIEF DESCRIPTION OF THE DRAWINGS
[0044] The invention is explained in more detail below with reference to the drawings, in which the single FIGURE shows an exemplary embodiment of an internal combustion engine having an exemplary embodiment of an exhaust gas turbocharger, an exemplary embodiment of a centrifugal compressor assembly, an exemplary embodiment of a centrifugal compressor and an exemplary embodiment of a compressor housing. DETAILED DESCRIPTION
[0045] The single FIGURE shows an exemplary embodiment of an internal combustion engine 1 having an exemplary embodiment of an exhaust gas turbocharger 3 , an exemplary embodiment of a centrifugal compressor assembly 5 , an exemplary embodiment of a centrifugal compressor 7 and an exemplary embodiment of a compressor housing 9 .
[0046] The exhaust gas turbocharger 3 has, in particular, a turbine wheel 13 which is arranged in the exhaust gas path 11 of the internal combustion engine 1 and is in driving operative connection with a compressor wheel 15 of the centrifugal compressor 7 .
[0047] The compressor housing 9 has a receiving space 17 for the compressor wheel 15, a flow-off region 19 and a collecting cavity 21. The compressor housing 9 also has a fluidic connection 23 between the collecting cavity 21 and the flow-off region 19 and a valve device 25, wherein the valve device 25 is arranged and configured to change the flow cross section of the fluidic connection 23 between the collecting cavity 21 and the flow-off region 19, in particular depending on parameters, in particular to selectively interrupt or open the fluidic connection 23.
[0048] In particular, at least one stationary guide blade 26 is arranged in the flow-off region 19 . The compressor wheel 15 has, in particular, at least one rotating guide blade 28 .
[0049] The centrifugal compressor assembly 5 has a control device 27 which is operatively connected to the valve device 25 and is designed to control the valve device 25, in particular as a function of at least one parameter. The at least one parameter is preferably selected from the group consisting of: pressure downstream of the centrifugal compressor 7, pressure loss across the centrifugal compressor 7, rotational speed of the compressor wheel 15, mass flow through the centrifugal compressor 7.
[0050] The control device 27 is designed in particular to control the valve device 25 into the open position when the operating state of the radial compressor 7 is in a predetermined characteristic curve region arranged adjacent to the surge limit.
[0051] The compressor housing 9 has in particular a first housing wall 29 which at least partially delimits the receiving space 17, the flow-off region 19 and the collecting cavity 21. At least one outflow opening 31 which opens into the collecting cavity 21 and at least one inflow opening 33 which opens into the flow-off region 19 are formed in the first housing wall 29, wherein the collecting cavity 21 is fluidically connected to the flow-off region 19 via the at least one outflow opening 31 and the at least one inflow opening 33.
[0052] The compressor housing 9 has in particular an annular space 35 into which the at least one outflow opening 31 on the one hand and the at least one inflow opening 33 on the other hand open, so that the collecting cavity 21 is fluidically connected to the outflow region 19 via the annular space 35 .
[0053] In the exemplary embodiment shown here, the compressor housing 9 has a second housing wall 37, which connects a collecting cavity wall section 39 of the first housing wall 29 to a flow-off region wall section 41 of the first housing wall 29. The annular space 35 is delimited in particular by the first housing wall 29 on the one hand and by the second housing wall 37 on the other hand.
[0054] The valve device 25 is designed, in particular, to selectively open and close at least one opening selected from the outflow opening 31 and the inflow opening 33 , in particular to selectively open and close the outflow opening 31 .
[0055] The first housing wall 29 has, in particular, a plurality of inflow openings 33 opening into the flow-off region 19, which are preferably arranged distributed at equal angular distances along the circumference about the rotation axis A of the compressor wheel 15. Alternatively or additionally, the first housing wall 29 has a plurality of outflow openings 31 opening into the collection chamber 21, which are preferably arranged distributed at equal angular distances along the circumference about the rotation axis A of the compressor wheel 15.
[0056] Preferably, at least one inflow opening 33 is of nozzle-shaped design, wherein it is in particular designed integrally with the first housing wall 29 , in particular formed therewith, or is however in particular inserted therein as a nozzle insert.
Claims
1. A compressor housing (9) for a centrifugal compressor (7), comprising a receiving space (17) for a compressor wheel (15), a flow-off region (19) and a collecting cavity (21), wherein: The compressor housing (9) has a fluidic connection (23) between the collecting cavity (21) and the flow-off region (19) and a valve device (25) which is arranged and configured to change the flow cross section of the fluidic connection (23) between the collecting cavity (21) and the flow-off region (19).
2. The compressor housing (9) according to claim 1, wherein: The compressor housing (9) has a first housing wall (29) which at least partially delimits the receiving space (17), the flow-away region (19) and the collecting cavity (21), wherein at least one outflow opening (31) which opens into the collecting cavity (21) and at least one inflow opening (33) which opens into the flow-away region (19) are formed in the first housing wall (29), wherein the collecting cavity (21) is fluidically connected to the flow-away region (19) via the at least one outflow opening (31) and the at least one inflow opening (33).
3. The compressor housing (9) according to claim 2, wherein: The compressor housing (9) has an annular space (35) into which the at least one outflow opening (31) and the at least one inflow opening (33) open on the one hand, so that the collecting cavity (21) is fluidically connected to the flow-off region (19) via the annular space (35).
4. The compressor housing (9) according to any one of claims 2 or 3, wherein: The compressor housing (9) has a second housing wall (37) which connects a collecting cavity wall section (39) of the first housing wall (29) to a flow-off region wall section (41) of the first housing wall (29), wherein in particular the annular space (35) is delimited by the first housing wall (29) and by the second housing wall (37).
5. The compressor housing (9) according to any one of claims 2 to 4, wherein: The valve device (25) is designed to selectively open and close at least one opening (31, 33) selected from the outflow opening (31) and the inflow opening (33).
6. The compressor housing (9) according to any one of claims 2 to 5, wherein: The first housing wall (29) has a plurality of inflow openings (33) opening into the outflow region (19), the inflow openings being arranged distributed at equal angular intervals along the circumference.
7. The compressor housing (9) according to any one of claims 2 to 6, wherein: The at least one inflow opening (33) is designed in the form of a nozzle.
8. A centrifugal compressor (7) having a compressor housing (9) according to any one of claims 1 to 7.
9. The centrifugal compressor (7) according to claim 8, wherein: A compressor wheel (15) is arranged in the receiving space (17), the compressor wheel having in particular at least one rotating guide blade (28).
10. A centrifugal compressor assembly (5), comprising a centrifugal compressor (7) according to any one of claims 8 or 9, and comprising a control device (27), which is effectively connected to the valve device (25) and is configured to control the valve device (25) in a manner particularly dependent on parameters.
11. The centrifugal compressor assembly (5) according to claim 10, wherein: The control device (27) is designed to control the valve device (25) into an open position when an operating state of the centrifugal compressor (7) is in a predetermined characteristic curve region arranged adjacent to a surge limit.
12. An exhaust gas turbocharger (3) having a centrifugal compressor (7) according to any one of claims 8 or 9, or having a centrifugal compressor assembly (5) according to any one of claims 10 or 11.
13. An internal combustion engine (1) having a centrifugal compressor (7) according to any one of claims 8 or 9, or having a centrifugal compressor assembly (5) according to any one of claims 10 or 11, or having an exhaust gas turbocharger (3) according to claim 12.