Self-circulation casing and centrifugal compressor

Abstract

The utility model provides a self-circulation casing and a centrifugal compressor, and belongs to the technical field of centrifugal compressors. The self-circulation casing comprises a casing body, a first rotating body and a second rotating body, wherein the casing body is rotationally sleeved with the first rotating body and the second rotating body. A suction ring groove is formed between the first rotating body and the second rotating body; the first rotating body and the second rotating body are suitable for generating axial displacement along the casing body during rotation so as to adjust the opening degree of the suction ring groove. According to the self-circulation casing provided by the invention, the position and interval of the suction ring groove of the self-circulation casing can be changed, so that the air entraining amount from the tail edge of the blade top to the front edge of the blade top is increased or decreased, the flowing condition of the blade top area of the movable blade is improved, and the optimal flowing control effect under different working conditions is achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of centrifugal compressors, and in particular relates to a self-circulating casing and a centrifugal compressor. Background Art

[0002] The centrifugal compressor works on the gas through the high-speed rotating blades, converting mechanical energy into kinetic energy and pressure energy of the gas. However, the stable operating condition of the centrifugal compressor is affected by its aerodynamic performance. Under low flow conditions, the centrifugal compressor will surge, resulting in drastic changes in flow parameters. In order to ensure the normal operation of the centrifugal compressor, on the one hand, it is necessary to try to avoid the centrifugal compressor entering the surge zone during operation, and on the other hand, flow control methods should be adopted to broaden the stable flow range of the centrifugal compressor.

[0003] In the related art, setting a suction ring groove on the casing is the simplest and most effective method to improve the compressor surge margin and widen the compressor flow range, that is, to create a channel near the compressor inlet so that the unstable turbulence generated by surge in the impeller area can be discharged through the channel, blocking the continued expansion and development of turbulence, and achieving the effect of widening the surge boundary. However, the axial position of the suction ring groove cannot be adjusted, which has great limitations and affects the suction effect. Utility Model Content

[0004] In order to solve at least one aspect of the technical problems existing in the background technology, the present application provides a self-circulating casing, which can realize the change of the position and interval interval of the suction ring groove of the self-circulating casing, thereby increasing or decreasing the amount of air intake from the trailing edge of the blade tip to the leading edge of the blade tip, improving the flow condition in the blade tip area, and achieving the optimal flow control effect under different working conditions.

[0005] A second aspect of the present application provides a centrifugal compressor.

[0006] The technical solution adopted in this application is:

[0007] The first aspect of the present application provides a self-circulating casing, comprising:

[0008] A casing body and a first rotating body and a second rotating body rotatably sleeved on the casing body;

[0009] A suction ring groove is formed between the first rotating body and the second rotating body;

[0010] The first rotating body and the second rotating body are suitable for generating axial displacement along the casing body when rotating, so as to adjust the opening and closing degree of the suction ring groove.

[0011] According to the self-circulating casing provided by the embodiment of the first aspect of the present application, a split design is adopted, which is divided into a fixed casing body, a first rotating body and a second rotating body. A suction ring groove is formed between the first rotating body and the second rotating body, and the first rotating body and the second rotating body can rotate around the axis of the casing. The rotation can adjust their axial positions on the casing body, thereby realizing the change of the gap width and position of the suction ring groove, and then changing the casing body's control over the on-off, flow rate and suction position of the gas flowing through, so as to realize the self-circulating casing to widen the surge boundary under low flow conditions, while reducing the pressure ratio and efficiency loss caused by the casing body under stable conditions.

[0012] According to one embodiment of the present application, the self-circulating casing further includes a rotation driver, the first rotating body includes a first rotating disk, and the second rotating body includes a second rotating disk;

[0013] The rotation driver drives the first rotating body to rotate via the first rotating disk, and the rotation driver drives the second rotating body to rotate via the second rotating disk.

[0014] According to an embodiment of the present application, a sealing cavity is formed on the outer periphery of the suction ring groove, and the inner wall of the sealing cavity is connected to the first rotating body and the second rotating body;

[0015] One end of the first rotating body connected to the casing body is formed with an internal thread adapted to the external thread of the casing body, one end of the first rotating body connected to the sealing chamber is formed with an external thread, and the inner wall of the sealing chamber is formed with an internal thread;

[0016] One end of the second rotating body connected to the casing body is formed with an internal thread adapted to the external thread of the casing body, one end of the second rotating body connected to the sealing chamber is formed with an external thread, and the inner wall of the sealing chamber is formed with an internal thread.

[0017] According to one embodiment of the present application, the first rotating body includes an inner layer and an outer layer, and a rib is provided between the inner layer and the outer layer;

[0018] The second rotating body includes an inner layer and an outer layer, and ribs are arranged between the inner layer and the outer layer.

[0019] According to one embodiment of the present application, the number of the ribs is 6 to 12 ribs evenly distributed within 360°.

[0020] According to an embodiment of the present application, the rotary driver comprises a motor, a steering link and a screw, and the motor drives the screw to move up and down along the axial direction of the casing through the steering link;

[0021] The first rotating disk and the second rotating disk are both meshed with the screw gear.

[0022] According to an embodiment of the present application, a connecting plate is provided between the first rotating disk and the first rotating body, and a connecting plate is provided between the second rotating disk and the second rotating body;

[0023] The number of the connecting plates is 4 to 6 evenly distributed within 360°.

[0024] According to an embodiment of the present application, rotation scale marking lines are provided on the first rotating disk and the second rotating disk.

[0025] According to an embodiment of the present application, the first rotating disk and the first rotating body are an integral structure, and the second rotating disk and the second rotating body are an integral structure.

[0026] A second aspect of the present application provides a centrifugal compressor, comprising a self-circulating casing in any embodiment of the first aspect as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 A schematic diagram of the structure of a self-circulating casing provided in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of the cross-sectional structure of the self-circulating casing provided in an embodiment of the present application.

[0030] in,

[0031] 1. casing body; 11. first rotating body; 111. first rotating disk; 12. second rotating body; 121. second rotating disk; 13. suction ring groove; 131. sealing chamber; 14. ribs; 15. motor; 16. steering link; 17. screw; 18. connecting plate. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below. It should be noted that the embodiments of the present application and the features in each embodiment may be combined with each other without conflict.

[0034] In addition, in the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0035] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0037] like Figure 1 to Figure 2 As shown, the first embodiment of the present application provides a self-circulating casing, including: a casing body 1 and a first rotating body 11 and a second rotating body 12 rotatably mounted on the casing body 1; a suction ring groove 13 is formed between the first rotating body 11 and the second rotating body 12; the first rotating body 11 and the second rotating body 12 are suitable for generating axial displacement along the casing body 1 during rotation to adjust the opening and closing degree of the suction ring groove 13.

[0038] A centrifugal compressor is a machine that increases the pressure of the airflow by doing work on the airflow through rotating blades. Surge is an aerodynamic instability phenomenon that occurs in turbomachinery. There is a violent airflow swallowing and puffing at the inlet of the supercharger, accompanied by blade vibration and abnormal noise. The casing 1 is a structure used to guide the gas that has entered the impeller to the flow groove when adverse pressure gradient flow occurs in the centrifugal compressor, and to re-flow from the impeller inlet to the impeller outlet.

[0039] According to the self-circulating casing provided by the embodiment of the first aspect of the present application, a split design is adopted, which is divided into a fixed casing body 1, a first rotating body 11 and a second rotating body 12. A suction ring groove 13 is formed between the first rotating body 11 and the second rotating body 12. The first rotating body 11 and the second rotating body 12 can rotate around the axis of the casing, and the rotation can adjust their axial positions on the casing body 1, thereby realizing the change of the gap width and position of the suction ring groove 13, and then changing the casing body 1 to control the on-off, flow rate and suction position of the gas flowing through, so as to realize the self-circulating casing to widen the surge boundary under low flow conditions, and at the same time reduce the pressure ratio and efficiency loss caused by the casing body 1 under stable conditions.

[0040] like Figure 1 to Figure 2 As shown, in some embodiments of the present application, the self-circulating casing further includes a rotation driver, the first rotating body 11 includes a first rotating disk 111, and the second rotating body 12 includes a second rotating disk 121; the rotation driver drives the first rotating body 11 to rotate through the first rotating disk 111, and the rotation driver drives the second rotating body 12 to rotate through the second rotating disk 121. The rotation driver is the power source of the entire device. The rotation driver can be an electric motor, or a hydraulic or pneumatic motor, etc. The first rotating disk 111 and the second rotating disk 121 are transmission components connecting the rotation driver and the first rotating body 11 and the second rotating body 12. When the rotation driver is started, it drives the first rotating disk 111 to rotate by gear transmission, belt transmission or direct coupling with the first rotating disk 111, and then drives the first rotating body 11 to rotate to change the axial position of the first rotating body 11 on the casing body 1, so as to adjust the position and opening degree of the suction ring groove 13. Similarly, the rotary driver can also drive the second rotating body 12 to rotate through the second rotating disk 121 , thereby driving the second rotating body 12 to rotate to change the axial position of the second rotating body 12 on the casing body 1 , thereby adjusting the position and opening degree of the suction ring groove 13 .

[0041] Furthermore, the rotation speed and direction of the first rotating disk 111 and the second rotating disk 121 can be controlled by a rotating driver, thereby accurately controlling the opening and closing state of the suction ring groove 13 to adapt to different working conditions.

[0042] like Figure 1 to Figure 2As shown, in some embodiments of the present application, a sealed cavity 131 is formed on the outer periphery of the suction ring groove 13, and the inner wall of the sealed cavity 131 is connected to the first rotating body 11 and the second rotating body 12; an end of the first rotating body 11 connected to the casing body 1 is formed with an internal thread adapted to the external thread of the casing body 1, and an end of the first rotating body 11 connected to the sealed cavity 131 is formed with an external thread, and an inner wall of the sealed cavity 131 is formed with an internal thread; an end of the second rotating body 12 connected to the casing body 1 is formed with an internal thread adapted to the external thread of the casing body 1, and an end of the second rotating body 12 connected to the sealed cavity 131 is formed with an external thread, and an inner wall of the sealed cavity 131 is formed with an internal thread. The inner wall of the sealing cavity 131 is connected to the first rotating body 11 and the second rotating body 12. When the rotating body is axially displaced, the inside of the casing body 1 is still effectively isolated from the outside. Through the sealing effect of the sealing cavity 131, even if the position of the rotating body changes, it can ensure that the gas inside the casing body 1 will not leak out from the outer periphery of the suction ring groove 13.

[0043] The first rotating body 11 and the second rotating body 12 are connected to the casing body 1 and the sealing chamber 131 by threaded connection. Specifically, the end of the first rotating body 11 connected to the casing body 1 has an internal thread, and the end connected to the sealing chamber 131 has an external thread; and the second rotating body 12 also follows the same design principle, that is, the end connected to the casing body 1 has an internal thread, and the end connected to the sealing chamber 131 has an external thread. This allows the rotating body to move along the axial direction while rotating, because the interaction of the threads can convert rotational motion into linear motion.

[0044] The inner wall of the sealing chamber 131 is also designed with internal threads. When the first rotating body 11 or the second rotating body 12 rotates, they will rise or fall along the inner wall threads of the sealing chamber 131, thereby changing the opening of the suction ring groove 13 and ensuring the sealing during the movement of the rotating body.

[0045] like Figure 1 to Figure 2 As shown, in some embodiments of the present application, the first rotating body 11 includes an inner layer and an outer layer, and a rib 14 is provided between the inner layer and the outer layer; the second rotating body 12 includes an inner layer and an outer layer, and a rib 14 is provided between the inner layer and the outer layer. The rib 14 provides support between the inner layer and the outer layer, enhances the structural strength of the first rotating body 11 and the second rotating body 12, and ensures the stability and reliability of the structure during rotation and axial displacement. The rib 14 also has a certain curvature, which can guide the gas sucked in, help guide the gas flow, reduce turbulence, and improve the stability of the gas flow, thereby optimizing the suction effect of the suction ring groove 13. It should be noted that the design of the rib 14 will not limit the axial movement of the first rotating body 11 and the second rotating body 12.

[0046] In some embodiments of the present application, the number of fins 14 is 6 to 12 evenly distributed within 360°. As supporting members, the number of fins 14 is just enough to ensure the structural stability between the inner and outer layers. Too many fins 14 will increase fluid resistance, while too few fins may not effectively guide the fluid flow. The range of 6 to 12 fins can better balance the two. Evenly distributed fins 14 can ensure balanced force distribution and avoid local stress concentration, thereby reducing structural fatigue and potential failure risks.

[0047] like Figure 1 to Figure 2 As shown, in some embodiments of the present application, the rotary driver includes a motor 15, a steering link 16 and a screw 17, and the motor 15 drives the screw 17 to move up and down along the axial direction of the casing body 1 through the steering link 16; the first rotating disk 111 and the second rotating disk 121 are both gear-engaged with the screw 17. The motor 15 serves as a power source to provide initial rotational power. When the motor 15 is started, it generates a rotational motion. The rotational motion of the motor 15 is transmitted to the screw 17 through the steering link 16, and the function of the steering link 16 is to convert the rotational motion of the motor 15 into a spiral lifting motion of the screw 17 in the axial direction. The first rotating disk 111 and the second rotating disk 121 can be gear-engaged with the screw 17, and when the screw 17 rotates, the rotating disk will be driven to rotate together. Since the rotating disk is fixedly connected to the corresponding rotating body, the rotation of the rotating disk will cause the rotating body to rotate around the casing axis. Since the rotating body is connected to the casing body 1 and the sealing chamber 131 through threads, when the rotating body rotates, they will produce axial displacement along the thread line direction. This displacement changes the relative position between the first rotating body 11 and the second rotating body 12, thereby adjusting the opening and position of the suction ring groove 13.

[0048] Furthermore, the screw 17 is a detachable structure, and can be engaged with the first rotating disk 111 and the second rotating disk 121 respectively, so as to drive the first rotating body 11 or the second rotating body 12 to rotate independently.

[0049] In addition, the first rotating disk 111 and the second rotating disk 121 can also be adjusted manually without relying on the input of a driving signal, so that the mechanical structure is more concise.

[0050] like Figure 1 to Figure 2As shown, in some embodiments of the present application, a connecting plate 18 is provided between the first rotating disk 111 and the first rotating body 11, and a connecting plate 18 is provided between the second rotating disk 121 and the second rotating body 12; the number of connecting plates 18 is 4 to 6 evenly distributed within 360°. Multiple connecting plates 18 can more evenly distribute the force generated during the rotation process, avoid excessive stress on a single connection point, and reduce structural fatigue and potential failure risks. The connecting plates 18 can improve the rigidity of the overall structure, making the rotating body more stable during rotation, reducing vibration and deformation. Multiple evenly distributed connecting plates 18 help ensure the coaxiality between the rotating body and the rotating disk, thereby ensuring the accuracy of the rotational motion. Setting 4 to 6 connecting plates 18 is to find a balance between performance requirements and cost. Too many connecting plates 18 will increase unnecessary weight and cost, while too few will not achieve the required structural strength and stability.

[0051] In some embodiments of the present application, a rotation scale marking line is provided on the first rotating disk 111 and the second rotating disk 121. The rotation scale marking line enables the operator or the control system to accurately measure the rotation angle of the rotating disk, thereby indirectly controlling the axial displacement of the first rotating body 11 and the second rotating body 12, and is particularly suitable for application scenarios in which the opening of the suction ring groove 13 is fine-tuned. By observing the position of the rotation scale marking line, the optimal configuration of the suction ring groove 13 under specific working conditions can be recorded so that these settings can be quickly reproduced under the same working conditions in the future, thereby improving work efficiency and consistency. The rotation scale marking line provides an intuitive interface, and the operator can directly see the rotation of the rotating disk without the need for additional sensors or instrument readings, which is convenient for manual adjustment or troubleshooting. For manual adjustment, the presence of the rotation scale marking line can simplify the operation process. The operator only needs to refer to the scale line to rotate the rotating disk to the desired position without the need for complex calculations or tools.

[0052] In some embodiments of the present application, the first rotating disk 111 is an integral structure with the first rotating body 11, and the second rotating disk 121 is an integral structure with the second rotating body 12. The integrated structure reduces the number of components, simplifies the overall structure, makes the device more compact, reduces weight, and reduces the complexity of manufacturing and assembly. The integrated design can improve the connection rigidity between the rotating body and the rotating disk, reduce vibration and displacement caused by loose or wear of the connecting parts, thereby improving the stability and reliability of the entire system. : Since there is no intermediate connecting part, the power transmission efficiency is higher and there is almost no energy loss, so that the output of the motor 15 can be more directly and efficiently converted into the rotational motion of the rotating body. The integrated structure reduces potential failure points, such as wear or looseness of the connecting parts, reduces maintenance requirements, and extends the service life of the device.

[0053] A second aspect of the present application provides a centrifugal compressor, comprising the self-circulating casing in any one of the embodiments of the first aspect.

[0054] According to the centrifugal compressor provided in the embodiment of the second aspect of the present application, the self-circulating casing therein adopts a split design, which is divided into a fixed casing body 1, a first rotating body 11 and a second rotating body 12. A suction ring groove 13 is formed between the first rotating body 11 and the second rotating body 12. The first rotating body 11 and the second rotating body 12 can rotate around the axis of the casing. The rotation can adjust their axial positions on the casing body 1, thereby realizing the change of the gap width and position of the suction ring groove 13, and then changing the casing body 1 to control the on-off, flow rate and suction position of the gas flowing through, so as to realize the self-circulating casing to widen the surge boundary under low flow conditions, and at the same time reduce the pressure ratio and efficiency loss caused by the casing body 1 under stable conditions. In summary, the centrifugal compressor provided in the embodiment of the present application can avoid surge phenomenon under low flow conditions and maintain an efficient and stable working state.

[0055] Anything not described in this application can be achieved by adopting or drawing on existing technologies.

[0056] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0057] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A self-circulating casing, characterized in that: include: A casing body (1), and a first rotating body (11) and a second rotating body (12) rotatably sleeved on the casing body (1); A suction ring groove (13) is formed between the first rotating body (11) and the second rotating body (12); The first rotating body (11) and the second rotating body (12) are suitable for generating axial displacement along the casing body (1) when rotating, so as to adjust the opening and closing degree of the suction ring groove (13).

2. The self-circulating casing according to claim 1, characterized in that: The self-circulating casing further comprises a rotation driver, the first rotating body (11) comprises a first rotating disk (111), and the second rotating body (12) comprises a second rotating disk (121); The rotary drive drives the first rotating body (11) to rotate via the first rotating disk (111), and the rotary drive drives the second rotating body (12) to rotate via the second rotating disk (121).

3. The self-circulating casing according to claim 2, characterized in that: A sealing cavity (131) is formed on the outer periphery of the suction ring groove (13), and the inner wall of the sealing cavity (131) is connected to the first rotating body (11) and the second rotating body (12); One end of the first rotating body (11) connected to the casing body (1) is formed with an internal thread adapted to the external thread of the casing body (1), one end of the first rotating body (11) connected to the sealing chamber (131) is formed with an external thread, and the inner wall of the sealing chamber (131) is formed with an internal thread; One end of the second rotating body (12) connected to the casing body (1) is formed with an internal thread adapted to the external thread of the casing body (1), one end of the second rotating body (12) connected to the sealing chamber (131) is formed with an external thread, and the inner wall of the sealing chamber (131) is formed with an internal thread.

4. The self-circulating casing according to claim 1, characterized in that: The first rotating body (11) comprises an inner layer and an outer layer, and a rib (14) is arranged between the inner layer and the outer layer; The second rotating body (12) comprises an inner layer and an outer layer, and a rib (14) is arranged between the inner layer and the outer layer.

5. The self-circulating casing according to claim 4, characterized in that: The number of the ribs (14) is 6 to 12 evenly distributed within 360°.

6. The self-circulating casing according to claim 2, characterized in that: The rotary driver comprises a motor (15), a steering connecting rod (16) and a screw rod (17); the motor (15) drives the screw rod (17) to move up and down along the axial direction of the casing body (1) via the steering connecting rod (16); The first rotating disk (111) and the second rotating disk (121) are both gear-engaged with the screw rod (17).

7. The self-circulating casing according to claim 6, characterized in that: A connecting plate (18) is provided between the first rotating disk (111) and the first rotating body (11), and a connecting plate (18) is provided between the second rotating disk (121) and the second rotating body (12); The number of the connecting plates (18) is 4 to 6 evenly distributed within 360°.

8. The self-circulating casing according to claim 6, characterized in that: The first rotating disk (111) and the second rotating disk (121) are both provided with rotation scale marking lines.

9. The self-circulating casing according to claim 2, characterized in that: The first rotating disk (111) and the first rotating body (11) are an integral structure, and the second rotating disk (121) and the second rotating body (12) are an integral structure.

10. A centrifugal compressor, characterized in that: It comprises a self-circulating casing as claimed in any one of claims 1 to 9.

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