A volute assembly, a centrifugal impeller machine and a design method of a volute assembly

Abstract

The application provides a volute assembly, a centrifugal impeller machine and a design method of the volute assembly, and belongs to the technical field of centrifugal impeller machines. The volute assembly comprises a first volute and a second volute. The first volute has a first gas collecting cavity, and a first diffuser pipe is connected to the outlet of the first gas collecting cavity. The second volute has a second gas collecting cavity, and a second diffuser pipe is connected to the outlet of the second gas collecting cavity. The first volute and the second volute are arranged side by side. An inner wall surface between the first volute and the second volute is provided with a common gas inlet of the first gas collecting cavity and the second gas collecting cavity. The first diffuser pipe and the second diffuser pipe are independent of each other. The gas entering the first gas collecting cavity and the second gas collecting cavity is discharged through the first diffuser pipe and the second diffuser pipe, respectively. The gas entering the volute is divided, so that the size of the equipment is effectively reduced, and the aerodynamic efficiency of the unit is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of centrifugal impeller machinery, in particular to a volute assembly, centrifugal impeller machinery and a design method of the volute assembly. BACKGROUND

[0002] With the continuous iteration and optimization design of compressed air energy storage technology, the scale of large-scale energy storage is continuously improved, and each subsystem needs to be matched synchronously. The design parameters of the compressor subsystem are further improved to save the energy storage time of the large-scale energy storage system.

[0003] As for the compressor subsystem, the improvement of the design parameters not only increases the difficulty of aerodynamic design, but also greatly hinders the structure arrangement and compression heat recovery. Specifically, the following aspects are shown: firstly, with the increase of the energy storage scale, the single-stage load of the compressor increases, which leads to the long and narrow meridian flow passage of the front-stage impeller, limits the improvement of the aerodynamic performance, and makes the downstream volute aerodynamic design more difficult; secondly, the increase of the energy storage scale makes the structure arrangement of the compressor subsystem more difficult. From the perspective of rotor dynamics, the short and thick axial arrangement helps to improve the rotor rigidity, so the structure arrangement of the compressor is limited, and the large-size volute is difficult to adapt to this scenario; thirdly, the increase of the load of each single-stage compressor in the compressor subsystem leads to the increase of the inter-stage heat of the compressor, which greatly improves the heat exchange power of the inter-stage heat exchanger, and the volume is too large to cause processing difficulties. Therefore, the single-stage heat exchanger cannot realize effective heat exchange, and the gas flow from the single volute outlet is difficult to be evenly distributed through the pipeline system, which reduces the efficiency of the entire compressor subsystem.

[0004] For the centrifugal impeller machinery, the centrifugal volute functions to collect, expand and slow down the gas discharged from the outlet of the upstream centrifugal impeller or runner. As a key component of the rotating impeller machinery, the design and improvement of the centrifugal volute structure has always been the direction of the pursuit of the ultimate aerodynamic performance of the whole machine. Among them, the asymmetric eccentric volute is recognized as having high aerodynamic performance. However, the gas flow from the single volute outlet is difficult to be evenly distributed through the pipeline system, which reduces the efficiency of the entire compressor subsystem. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to overcome the defect that the gas from the outlet of the centrifugal volute is difficult to be evenly distributed, so as to provide a volute assembly, centrifugal impeller machinery and a design method of the volute assembly.

[0006] In order to solve the above technical problems, the present application provides a volute assembly, comprising:

[0007] The first volute has a first gas collecting cavity, and a first diffuser pipe is connected to the outlet of the first gas collecting cavity;

[0008] a second volute having a second plenum, and a second diffuser pipe connected to an outlet of the second plenum;

[0009] The first volute and the second volute are arranged side by side, and a common gas inlet of the first plenum and the second plenum is formed on an inner wall surface between the first volute and the second volute; the first diffuser pipe and the second diffuser pipe are independent of each other, and gas entering the first plenum and the second plenum is discharged through the first diffuser pipe and the second diffuser pipe, respectively.

[0010] Optionally, the first volute and the second volute are both asymmetric eccentric volutes.

[0011] Optionally, the first volute and the second volute have the same size in meridian section.

[0012] Optionally, one half of the gas inlet is directed to the first plenum, and the other half of the gas inlet is directed to the second plenum.

[0013] Optionally, the first diffuser pipe and the second diffuser pipe have the same size.

[0014] Optionally, the first plenum and the second plenum have an extension edge extending in the direction of the gas inlet on a side away from the gas inlet.

[0015] Optionally, the first volute and the second volute are integrally cast.

[0016] The present application provides a centrifugal impeller machine, comprising a runner and the volute assembly according to any one of the above.

[0017] The gas inlet of the volute assembly is connected to an outlet of the runner.

[0018] Optionally, the runner has a ring structure, and the structure of the outlet of the runner relative to the first plenum and relative to the second plenum is the same.

[0019] The present application provides a design method of a volute assembly, comprising the following steps:

[0020] determining aerodynamic parameters of the volute as a whole;

[0021] determining meridian structure sizes of the volute as a whole according to the aerodynamic parameters, wherein the meridian structure sizes include a meridian parameter radial size and a meridian parameter width size;

[0022] designing a first volute: the meridian parameter width size of the first volute is half of the meridian parameter width size of the volute as a whole, and then performing aerodynamic design of the first volute to obtain a three-dimensional structure model of the first volute;

[0023] designing a second volute: according to the structure of the first volute, a three-dimensional structural model of the second volute is designed symmetrically;

[0024] The three-dimensional structural model of the first volute and the three-dimensional structural model of the second volute are assembled to obtain the three-dimensional structural model of the volute assembly of any one of the above.

[0025] The technical scheme of the present application has the following advantages:

[0026] 1. The volute assembly provided by the present application comprises a first volute and a second volute arranged oppositely, the first volute has a first gas collecting cavity, and a first diffuser pipe is connected to the outlet of the first gas collecting cavity; the second volute has a second gas collecting cavity, and a second diffuser pipe is connected to the outlet of the second gas collecting cavity; the first volute and the second volute are arranged side by side, and a common gas inlet of the first gas collecting cavity and the second gas collecting cavity is formed on the inner wall surface between the first volute and the second volute; the first diffuser pipe and the second diffuser pipe are independent of each other, and the gas entering the first gas collecting cavity and the second gas collecting cavity is discharged through the first diffuser pipe and the second diffuser pipe, respectively. The arrangement of the first gas collecting cavity and the second gas collecting cavity divides the gas entering the volute, improves the efficiency of the compressor subsystem, reduces the thermal load of the downstream heat exchanger, and reduces the design difficulty of the heat exchanger, thereby improving the aerodynamic performance of the whole machine. Through the structural arrangement of the first volute and the second volute, the original volute is split at the design level, the design process of a single volute is simple, and the aerodynamic design difficulty is reduced. In terms of the overall size, this structure effectively reduces the overall size of the whole unit, especially the radial size, which is beneficial to the structural arrangement of the whole compressor subsystem.

[0027] 2. In the volute assembly provided by the present application, the first volute and the second volute are both asymmetric eccentric volutes, which have high aerodynamic efficiency. The application of asymmetric eccentric volutes in the volute assembly effectively combines the advantages of asymmetric eccentric volutes in aerodynamic performance and takes into account the structural arrangement of the whole compressor subsystem.

[0028] 3. In the volute assembly provided by the present application, the meridian section of the first volute and the meridian section of the second volute have the same size, the two gas flows entering the first gas collecting cavity and the second gas collecting cavity have consistent state parameters, accurate gas flow division can be achieved, the design difficulty is reduced at the design level, and the size of the whole unit is also reduced.

[0029] 4. In the volute assembly provided by the present application, half of the gas inlet is directed towards the first gas collecting cavity, and the other half of the gas inlet is directed towards the second gas collecting cavity, which is beneficial to the gas flow entering the gas inlet and being divided into two uniform gas flows. In combination with the first volute and the second volute having the same size, the same state parameters of the two gas flows are further ensured, and the design difficulty is reduced.

[0030] 5. The volute assembly provided by the present application, the first diffuser and the second diffuser have the same size, so that the air flow discharged from the first diffuser and the second diffuser is completely the same, and the two air flows need to design the same downstream equipment, thereby reducing the design difficulty and cost of the subsequent downstream heat exchanger or other equipment.

[0031] 6. The volute assembly provided by the present application, the side of the first gas collecting cavity and the second gas collecting cavity away from the air inlet has an extension edge extending towards the air inlet direction, the setting of the extension edge can make the two air flows after flow separation move independently in the respective gas collecting cavities, further improve the flow separation effect, and also be beneficial to the air flow discharged from the corresponding first diffuser or second diffuser.

[0032] 7. The volute assembly provided by the present application, the first volute and the second volute are integrally cast structures, through integrally casting forming, the strength of the volute is improved, the gap and other conditions of the combined installation are avoided, the diffusing effect of the volute is improved, and the efficiency of the compressor is improved.

[0033] 8. The centrifugal impeller machine provided by the present application, including a runner and a volute assembly, the air discharged from the runner enters the air inlet of the volute assembly and is flow-separated to form two air flows with the same state parameters, thereby reducing the overall size of the centrifugal impeller machine, improving the efficiency of the compressor subsystem, reducing the heat load of the downstream heat exchanger, reducing the design difficulty of the heat exchanger, and improving the aerodynamic performance of the whole machine.

[0034] 9. The centrifugal impeller machine provided by the present application, the outlet of the runner has the same structure relative to the first gas collecting cavity and the second gas collecting cavity, in the process of completing the flow separation of the air flow, only the structure of the volute itself is used to realize the flow separation, without the need of special modification of the runner, which is suitable for the conventional runner, has low design cost and strong universality.

[0035] 10. The design method of the volute assembly provided by the present application, from the perspective of aerodynamic design, the inlet width of the first volute and the second volute is half of the outlet width of the upstream runner, the airflow is divided along the height direction of the runner at the interface between the runner and the volute, so that the original airflow is divided into two uniform airflows, the two airflows have approximately identical state parameters, and then pass through two identical volute structures, so that the perfect airflow division is achieved in a strict sense. Therefore, for each volute, the mass flow of the through-flowing gas is half of the original design parameter, under the premise of identical state parameters, the area of the cross section at the outlet of the volute is also half of the original, which reduces the aerodynamic design difficulty of the volute and effectively reduces the size of the volute. In addition, the uniform division of the single airflow into two airflows reduces the design difficulty of the heat exchanger and improves the heat exchange efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the specific embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0037] Figure 1 A structural schematic diagram of one specific embodiment of the volute assembly provided in the embodiments of the present application;

[0038] Figure 2 A structural schematic diagram of one specific embodiment of the volute assembly provided in the embodiments of the present application; Figure 1 A sectional structural schematic diagram of the first volute and the second volute.

[0039] Explanation of reference signs:

[0040] 1, first volute; 2, first plenum; 3, first diffuser; 4, second volute; 5, second plenum; 6, second diffuser; 7, inlet. DETAILED DESCRIPTION

[0041] The technical solutions of the present application will be described in detail below with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, but not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0042] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the 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 particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0043] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0044] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as there is no conflict.

[0045] The volute assembly provided in the embodiment is used in a centrifugal impeller machine, which realizes uniform division of the gas flow into two streams in the centrifugal impeller machine, plays a role of flow division, effectively reduces the size of the equipment, and improves the aerodynamic efficiency of the unit.

[0046] As Figure 1 and Figure 2 shown, a specific embodiment of the volute assembly provided in the embodiment includes a first volute 1 and a second volute 4, the first volute 1 has a first gas collecting chamber 2, and a first diffuser pipe 3 is communicated at the outlet of the first gas collecting chamber 2; the second volute 4 has a second gas collecting chamber 5, and a second diffuser pipe 6 is communicated at the outlet of the second gas collecting chamber 5; the first volute 1 and the second volute 4 are arranged side by side, and a common gas inlet 7 of the first gas collecting chamber 2 and the second gas collecting chamber 5 is formed on the inner wall surface between the first volute 1 and the second volute 4; the first diffuser pipe 3 and the second diffuser pipe 6 are independent of each other, and the gas entering the first gas collecting chamber 2 and the second gas collecting chamber 5 is discharged through the first diffuser pipe 3 and the second diffuser pipe 6, respectively.

[0047] The first gas collecting cavity 2 and the second gas collecting cavity 5 are arranged to split the gas entering the volute, and the split gas flows are discharged from the first diffuser pipe 3 and the second diffuser pipe 6 respectively and connected to downstream devices respectively, thereby improving the efficiency of the compressor subsystem, reducing the heat load of the downstream heat exchanger, reducing the design difficulty of the heat exchanger, and improving the aerodynamic performance of the whole machine; and the original volute is split in the design level through the structural arrangement of the first volute 1 and the second volute 4, the design process of the single volute is simple, and the aerodynamic design difficulty is reduced; in terms of the size, the structure effectively reduces the size of the whole unit, especially the radial size, which is beneficial to the structural arrangement of the whole compressor subsystem.

[0048] As shown in Figure 1 , in the volute assembly provided in the embodiment, the first volute 1 and the second volute 4 are both asymmetric eccentric volutes. The asymmetric eccentric volute has high aerodynamic efficiency, and the application of the asymmetric eccentric volute in the volute assembly effectively combines the advantages of the asymmetric eccentric volute in the aerodynamic performance and takes into account the structural arrangement of the whole compressor subsystem. In addition, as an alternative embodiment, the first volute 1 and the second volute 4 can also be symmetric volutes.

[0049] As shown in Figure 1 and Figure 2 , in the volute assembly provided in the embodiment, the first volute 1 and the second volute 4 have the same size in the meridian section. The two gas flows entering the first gas collecting cavity 2 and the second gas collecting cavity 5 have consistent state parameters, which can achieve accurate gas flow splitting, reduce the design difficulty at the design level, and reduce the size of the whole unit.

[0050] As shown in Figure 1 and Figure 2 , in the volute assembly provided in the embodiment, half of the gas inlet 7 is directed to the first gas collecting cavity 2, and the other half of the gas inlet 7 is directed to the second gas collecting cavity 5. This is beneficial to the uniform splitting of the gas flow into two uniform gas flows after entering the gas inlet 7, and further ensures the same state parameters of the two gas flows by cooperating with the first volute 1 and the second volute 4 having the same size, thereby achieving uniform gas flow splitting and reducing the design difficulty.

[0051] As shown in Figure 1 , in the volute assembly provided in the embodiment, the first diffuser pipe 3 and the second diffuser pipe 6 have the same size. The gas flows discharged from the first diffuser pipe 3 and the second diffuser pipe 6 are exactly the same, and the same downstream devices need to be designed for the two gas flows, thereby reducing the design difficulty and cost of the subsequent downstream heat exchanger or other devices.

[0052] As shown in Figure 1 and Figure 2As shown, in the volute assembly provided in the embodiment, the side of the first gas collecting cavity 2 and the second gas collecting cavity 5 away from the gas inlet 7 has an extension edge extending towards the gas inlet 7. The length of the extension edge can be selected according to actual conditions. The extension edge is arranged to make the two gas flows after the flow splitting move independently in the respective gas collecting cavities, further improve the flow splitting effect, and also facilitate the discharge of the gas flow from the corresponding first diffuser pipe 3 or second diffuser pipe 6.

[0053] In the volute assembly provided in the embodiment, the first volute 1 and the second volute 4 are integrally cast. Through integrally casting, the strength of the volute is improved, the gaps that occur in the combined installation are avoided, the machining precision of the volute as a whole is further ensured, the diffusing effect of the volute is improved, and thus the efficiency of the compressor is improved. In addition, as an alternative embodiment, the first volute 1 and the second volute 4 can also be made separately and then assembled and fixed.

[0054] The embodiment also provides a centrifugal impeller machine, which comprises a runner and the volute assembly described in the above embodiment, and the gas inlet 7 of the volute assembly is in communication with the outlet of the runner. The gas discharged from the runner enters the gas inlet 7 of the volute assembly to be split into two gas flows with consistent state parameters, which reduces the overall size of the centrifugal impeller machine, improves the efficiency of the compressor subsystem, reduces the thermal load of the downstream heat exchanger, reduces the design difficulty of the heat exchanger, and thus improves the aerodynamic performance of the whole machine.

[0055] In the centrifugal impeller machine provided in the embodiment, the runner is of an annular structure, and the outlet of the runner is relatively identical in structure to the first gas collecting cavity 2 and the second gas collecting cavity 5. In the process of splitting the gas flow into two, the splitting is achieved only through the structure of the volute itself, without the need for special modification of the runner, which is suitable for a conventional runner and has low design cost and strong universality.

[0056] The embodiment also provides a design method of a volute assembly, which comprises the following steps:

[0057] determining the aerodynamic parameters of the volute as a whole, wherein the aerodynamic parameters include the axial velocity, the tangential velocity, the total temperature, the total pressure, the density and the like;

[0058] determining the meridian structure size of the volute as a whole according to the aerodynamic parameters, wherein the meridian structure size includes the meridian parameter radial size and the meridian parameter width size;

[0059] designing the first volute 1: the meridian parameter width size of the first volute 1 is half of the meridian parameter width size of the volute as a whole, and then the aerodynamic design of the first volute 1 is performed to obtain a three-dimensional structure model of the first volute 1;

[0060] Designing the second volute 4: according to the structure of the first volute 1, a three-dimensional structure model of the second volute 4 is designed symmetrically;

[0061] Assembling the three-dimensional structure model of the first volute 1 and the three-dimensional structure model of the second volute 4 to obtain the three-dimensional structure model of the volute assembly in the above embodiment.

[0062] From the perspective of aerodynamic design, the inlet width of the first volute 1 and the second volute 4 is half of the outlet width of the upstream runner, and the airflow is divided along the height direction of the runner at the interface between the runner and the volute, so that the original airflow is divided into two uniform airflows with approximately identical state parameters, and then passes through two identical volute structures, so that the airflow is perfectly divided in a strict sense. Therefore, for each volute, the mass flow of the through-flowing gas is half of the original design parameter, and under the premise of identical state parameters, the area of the cross section at the outlet of the volute is also half of the original, which reduces the difficulty of aerodynamic design of the volute and effectively reduces the size of the volute. In addition, the uniform division of a single airflow into two airflows reduces the heat exchange load of the downstream heat exchanger device to half of the original, which reduces the design difficulty of the heat exchanger and improves the heat exchange efficiency.

[0063] The flow process of the airflow in the volute: the airflow enters the volute assembly from the inlet 7, and after passing through the inlet 7, the airflow is divided into two airflows which enter the first plenum 2 and the second plenum 5 respectively. The two airflows with identical state parameters move in the first plenum 2 and the second plenum 5 respectively, and then the airflow in the first plenum 2 is discharged from the first diffuser pipe 3, and the airflow in the second plenum 5 is discharged from the second diffuser pipe 6, completing the process of dividing a single airflow into two airflows. The mass flow of each airflow is half of the original design parameter, and under the premise of identical state parameters, the area of the cross section at the connection between the volute and the diffuser pipe is also half of the original, which reduces the difficulty of aerodynamic design of the volute and effectively reduces the size of the volute. In the design of the downstream heat exchanger device, the heat exchange load can be reduced to half of the original, which reduces the design difficulty of the heat exchanger and improves the heat exchange efficiency.

[0064] Obviously, the above embodiments are only examples for clear illustration, and are not limitations on the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. All embodiments do not need to be exhausted, and obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A design method for a volute assembly, characterized in that: The volute assembly includes: The first volute (1) has a first gas collecting chamber (2), and the outlet of the first gas collecting chamber (2) is connected to a first diffuser (3). The second volute (4) has a second gas collecting chamber (5), and the outlet of the second gas collecting chamber (5) is connected to a second diffuser (6). The first volute (1) and the second volute (4) are arranged side by side, and the first gas collecting chamber (2) and the second gas collecting chamber (5) are formed on the inner wall surface between the first volute (1) and the second volute (4); the first diffuser (3) and the second diffuser (6) are independent of each other, and the gas entering the first gas collecting chamber (2) and the second gas collecting chamber (5) is discharged through the first diffuser (3) and the second diffuser (6) respectively; Both the first volute (1) and the second volute (4) are asymmetrical eccentric volutes; The first volute (1) and the second volute (4) have the same external dimensions in their meridional cross sections; Half of the air inlet (7) faces the first air collection chamber (2), and the other half of the air inlet (7) faces the second air collection chamber (5). The first diffuser tube (3) and the second diffuser tube (6) have the same external dimensions; The first gas collecting chamber (2) and the second gas collecting chamber (5) have an extension side that extends toward the air inlet (7) on the side away from the air inlet (7); The first volute (1) and the second volute (4) are integrally cast structures; The design methodology includes the following steps: Determine the overall aerodynamic parameters of the volute; The meridional structural dimensions of the entire volute are determined based on the aerodynamic parameters, and the meridional structural dimensions include the radial dimension and the width dimension of the meridional parameters. Design the first volute (1): The meridional parameter width dimension of the first volute (1) is half of the meridional parameter width dimension of the entire volute. Then, the aerodynamic design of the first volute (1) is carried out to obtain the three-dimensional structural model of the first volute (1). Design the second volute (4): Based on the structure of the first volute (1), design the three-dimensional structural model of the second volute (4) symmetrically; The three-dimensional structural model of the first volute (1) and the three-dimensional structural model of the second volute (4) are assembled to obtain the three-dimensional structural model of the volute assembly.

2. A centrifugal impeller machine, characterized in that, The volute assembly includes a rotating wheel and a volute assembly designed using the design method described in claim 1; The air inlet of the volute assembly is connected to the outlet of the rotor.

3. The centrifugal impeller machine according to claim 2, characterized in that, The impeller has a ring structure, and the outlet of the impeller has the same structure relative to the first gas collecting chamber (2) and relative to the second gas collecting chamber (5).

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