Centrifugal compressors, air conditioners

Abstract

The present invention provides a centrifugal compressor and air conditioner, which belong to the field of compressor design, wherein the centrifugal compressor includes: a volute, in which an impeller is provided; a diffuser panel, forming an outlet flow channel between the volute and the volute; an air intake hood, which is located on the air intake side of the impeller, and has an air intake port, and an internal circulation air supply port connected to the air intake port; the fluid in the outlet flow channel can be controlled to be connected to the internal circulation air supply port. When the compressor is running at low load, the present invention can guide the fluid in the outlet flow channel to the air intake port of the compressor. By actively diverting the air flow of the compressor, the flow demand for stable operation of the impeller can be guaranteed, and the volute outlet flow can meet the demand for lower loads, effectively avoiding surge in the compressor and broadening the operating range of the compressor.

Description

Technical Field

[0001] The invention belongs to the field of compressor design, and in particular relates to a centrifugal compressor and an air conditioner. Background Art

[0002] Centrifugal compressors, when used for applications such as refrigeration, offer advantages such as high load capacity, stable operation, and high efficiency, and are therefore highly valuable in industrial applications. However, a major drawback of centrifugal compressors is their surge limitations at low loads. When the compressor operates at low speeds and flow rates, insufficient impeller output pressure results, leading to backflow through the volute and severe vibration damage to the unit. This present invention addresses these issues. Summary of the Invention

[0003] Therefore, the present invention provides a centrifugal compressor and an air conditioner, which can solve the technical problem in the prior art that the centrifugal compressor surges when running at low load, causing vibration damage to the unit.

[0004] In order to solve the above problems, the present invention provides a centrifugal compressor, comprising:

[0005] a volute, wherein an impeller is provided in the volute;

[0006] a diffuser panel, forming an outflow channel with the volute;

[0007] An air suction hood is located on the air suction side of the impeller, and has an air suction port and an internal circulation air supply port connected to the air suction port;

[0008] The fluid in the outflow channel can be controlled to communicate with the internal circulation air supply port.

[0009] In some embodiments,

[0010] An internal circulation flow channel is constructed in the air suction hood and is connected with the internal circulation air supply port and is controllably connected with the outflow flow channel.

[0011] In some embodiments,

[0012] The internal circulation flow channel includes a throttling section connected to the internal circulation air supply port.

[0013] In some embodiments,

[0014] The internal circulation flow channel also includes a collecting chamber arranged around the air intake port, and there are multiple internal circulation air supply ports, and the multiple internal circulation air supply ports are evenly spaced around the air intake port. There are multiple throttling sections, and the multiple throttling sections are arranged in a one-to-one correspondence with the multiple internal circulation air supply ports, and the multiple throttling sections are evenly spaced around the collecting chamber, and the throttling sections are connected between the collecting chamber and the internal circulation air supply port.

[0015] In some embodiments,

[0016] It also includes an on-off control component. The diffuser panel is provided with a flow hole connected to the outflow channel. The on-off control component can control the on-off between the flow hole and the manifold.

[0017] In some embodiments,

[0018] The on-off control component includes a rotating disk and a rotating drive member for driving the rotating disk to rotate. The rotating disk is mounted on the diffuser panel. The rotating disk has an on-off component. During the rotation of the rotating disk, the on-off component can connect or cut off the flow through hole and the manifold.

[0019] In some embodiments,

[0020] The on-off assembly includes a sealing ball and an elastic member that applies elastic force to the side of the sealing ball away from the flow hole, and the sealing ball has a cut-off state in which it is partially inside the flow hole and a conducting state outside the flow hole; and / or, the rotating disk passes through a sliding bearing.

[0021] In some embodiments,

[0022] There are multiple through-flow holes, and the multiple through-flow holes are evenly spaced around the diffuser panel. There are multiple on-off components, and the multiple on-off components are arranged in a one-to-one correspondence with the multiple through-flow holes.

[0023] In some embodiments,

[0024] The area between two adjacent on-off components is a first area. A flow groove is configured on the rotating disk corresponding to the first area. The flow groove connects the flow hole and the manifold.

[0025] In some embodiments,

[0026] The outer circumferential wall of the rotating disk is provided with a plurality of driving teeth arranged along the circumference thereof. The rotating driving member is connected to the volute and is arranged adjacent to the rotating disk. The rotating driving member includes a rotating wheel, and the rotating wheel is engaged with the driving teeth.

[0027] The present invention also provides an air conditioner, comprising the centrifugal compressor.

[0028] The present invention provides a centrifugal compressor and air conditioner. When the compressor is running at low load, the fluid in the outlet flow channel can be guided to the suction port of the compressor. By actively diverting the air flow of the compressor, the flow demand for stable operation of the impeller can be guaranteed, and the flow at the volute outlet can be achieved to meet the demand for lower load, thereby effectively avoiding surge of the compressor and broadening the operating range of the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the internal structure of a centrifugal compressor according to an embodiment of the present invention;

[0030] Figure 2 for Figure 1 The fluid flow direction when the through-hole is cut off (when the centrifugal compressor is operating at a higher speed);

[0031] Figure 3 for Figure 1 The fluid flow direction when the through hole in is opened (when the centrifugal compressor is operating at a lower speed);

[0032] Figure 4 for Figure 1 Schematic diagram of the relative position relationship between the rotating disk and the rotating wheel;

[0033] Figure 5 for Figure 1 The other side of the rotating disk (with Figure 4 A schematic diagram of the structure of the side opposite to the side in FIG);

[0034] Figure 6 for Figure 1 Schematic diagram of the longitudinal section of the rotating disk.

[0035] The reference numerals indicate:

[0036] 11. Volute; 111. Outlet flow channel; 12. Impeller; 121. Rotating shaft; 122. Locking screw; 123. Motor end cover; 124. Support bearing; 125. Main drive motor; 13. Diffuser panel; 131. Flow hole; 14. Suction hood; 141. Suction port; 142. Internal circulation air supply port; 143. Throttling section; 144. Manifold; 21. Rotating disk; 211. Flow groove; 22. Rotating drive member; 221. Impeller; 231. Sealing ball; 232. Elastic member; 233. Positioning screw; 24. Sliding bearing. DETAILED DESCRIPTION

[0037] See also Figures 1 to 6As shown, according to an embodiment of the present invention, a centrifugal compressor is provided, comprising: a volute 11, an impeller 12 is provided in the volute 11, and the air flow driven by the impeller 12 is discharged from the compressor through the air outlet on the volute 11. It can be understood that the impeller 12 is fixed to the rotating shaft 121 by a locking screw 122. The rotating shaft 121 is the rotating shaft of the corresponding drive motor, which is not described here; a diffuser panel 13, which is connected to one side of the volute 11 to form an outlet flow channel 111 between the volute 11, and the outlet position of the outlet flow channel 111 is the aforementioned air outlet; an air intake hood 14, which is on the air intake side of the impeller 12, in a specific In the embodiment, the air intake hood 14 is detachably connected to the volute 11, and the diffuser panel 13 is located in the area between the volute 11 and the air intake hood 14. The air intake hood 14 has an air intake port 141 and an internal circulation air supply port 142 connected to the air intake port 141. It can be understood that for a centrifugal compressor, the impeller 12 is an axial inlet flow, so the air intake port 141 is coaxial with the rotation axis of the impeller 12; the fluid in the outlet flow channel 111 can be controlled to be connected to the internal circulation air supply port 142, that is, the fluid in the outlet flow channel 111 can be controlled to be connected to the air intake port 141 via the internal circulation air supply port 142. In a specific embodiment, the aforementioned fluid is a refrigerant, and the centrifugal compressor is used in a refrigeration system. Of course, in some other application conditions, the aforementioned fluid can also be air.

[0038] In this technical solution, when the compressor is running at low load, the fluid in the outlet flow channel 111 can be guided to the suction port 141 of the compressor. By actively diverting the air flow of the compressor, the flow demand for stable operation of the impeller can be guaranteed, and the flow at the volute outlet can be achieved to meet the demand for lower load, effectively avoiding surge in the compressor and broadening the operating range of the compressor.

[0039] In some embodiments, an internal circulation flow channel is constructed in the air intake hood 14, which is connected to the internal circulation air supply port 142 and is controllably connected to the outlet flow channel 111. By directly constructing the aforementioned internal circulation flow channel in the air intake hood 14, there is no need to set up independently assembled pipes for the internal circulation flow path, which simplifies the assembly and makes the structural design of the centrifugal compressor more compact.

[0040] In a specific embodiment, the internal circulation flow channel includes a throttling section 143 connected to the internal circulation air supply port 142. The aforementioned throttling section 143 is also a section of the flow channel with a smaller flow area. It can appropriately throttle and reduce the pressure of the high-pressure fluid drained from the outlet flow channel 111 to prevent its pressure from being too different from the pressure at the intake port 141. In this way, it can effectively prevent the excessively high-pressure drainage fluid from disturbing the airflow at the intake port 141 and reduce the intake resistance.

[0041] In some embodiments, the internal circulation flow channel further includes a manifold 144 arranged around the air intake port 141, a plurality of internal circulation air supply ports 142, and the plurality of internal circulation air supply ports 142 are evenly spaced around the air intake port 141. A plurality of throttling sections 143 are arranged in a one-to-one correspondence with the plurality of internal circulation air supply ports 142, and the plurality of throttling sections 143 are evenly spaced around the manifold 144, and the throttling sections 143 are connected between the manifold 144 and the internal circulation air supply ports 142. In this technical solution, the manifold 144 is arranged around the air intake port 141 and has a plurality of throttling sections 143 and internal circulation air supply ports 142 arranged in a circular manner, which can ensure that the fluid drawn in is evenly introduced in the circumferential direction of the air intake port 141, further reducing adverse disturbances to the inhalation airflow. In a specific embodiment, the outflow direction of each internal circulation air supply port 142 is arranged along the radial direction of the air intake port 141 , that is, perpendicular to the axial direction of the air intake port 141 .

[0042] The centrifugal compressor also includes an on-off control component (not labeled in the figure). The diffuser panel 13 is provided with a flow hole 131 connected to the outlet flow channel 111. The on-off control component can control the on-off between the flow hole 131 and the collecting chamber 144. The flow hole 131 is arranged on the diffuser panel 13, which can further simplify the design of the internal circulation flow path. Based on this structure, the on-off control component can be used to control the on-off between the flow hole 131 and the collecting chamber 144.

[0043] As a preferred embodiment of the on-off control component, the on-off control component includes a rotating disk 21 and a rotating drive member 22 for driving the rotating disk 21 to rotate. The rotating disk 21 is mounted on the diffuser panel 13, that is, the central area of ​​the rotating disk 21 has a corresponding through hole, through which the rotating disk 21 and the diffuser panel 13 are mounted. The rotating disk 21 has an on-off component (not marked in the figure). During the rotation of the rotating disk 21, the on-off component can connect or disconnect the flow hole 131 and the manifold 144. In this technical solution, the on-off of the on-off component is associated with the rotation position of the rotating disk 21. For example, when the rotating disk 21 is in a certain position, the on-off component is turned on, and when the rotating disk 21 is driven to rotate an angle and is in another position, the on-off component is disconnected. The on-off control of the on-off component is more flexible and reliable.

[0044] The rotating disk 21 is assembled with the corresponding structure of the diffuser panel 13 through the sliding bearing 24, which can ensure smooth and reliable rotation of the rotating disk 21.

[0045] In a specific embodiment, the rotating disk 21 has a corresponding accommodating hole, and the on-off assembly is accommodated in the accommodating hole. Specifically, the on-off assembly includes a sealing ball 231 and an elastic member 232 that applies elastic force to the sealing ball 231 on the side away from the flow hole 131. The sealing ball 231 has a cut-off state in which it is partially inside the flow hole 131 and a conducting state outside the flow hole 131. Specifically, as the rotating disk 21 rotates, the sealing ball 231 will enter or escape from the corresponding flow hole 131. When the sealing ball 231 enters the flow hole 131, it is in the aforementioned cut-off state, and when the sealing ball 231 escapes from the flow hole 131, it is in the aforementioned conducting state. Through such a structure, the elastic force of the elastic member 232 (such as a spring) combined with the rotation of the rotating disk 21 is used to realize the conduction and cutoff of the internal circulation. The structure is simple and compact, and the operation is reliable. Figure 6 As shown, the end of the receiving hole facing away from the diffuser panel 13 has a corresponding positioning screw 233, which is used to position the elastic member 232. The specific structure of the sealing ball 231 is not limited. In principle, any shape that can smoothly contact, such as an arc or an ellipse, can be applied to the structure.

[0046] See also Figure 4 and Figure 5 As shown, in a preferred embodiment, there are multiple flow holes 131, and the multiple flow holes 131 are evenly spaced in the annular diffuser panel 13. There are multiple on-off components, and the multiple on-off components are arranged one-to-one corresponding to the multiple flow holes 131. In this way, the higher-pressure fluid introduced from the outlet flow channel 111 can be throttled and reduced in pressure and then enter the air intake port 141 more evenly through the internal circulation air supply port 142, and participate in the internal circulation of the fluid more smoothly.

[0047] See also Figure 5 In a preferred embodiment, the area between two adjacent on-off components is the first area. A flow groove 211 is constructed on the rotating disk 21 corresponding to the first area. The flow groove 211 connects the flow hole 131 and the manifold 144. Through the setting of the flow groove 211, the side of the rotating disk 21 and the corresponding side of the diffuser panel 13 can have a flow function while forming a small gap contact, thereby ensuring the position reliability of the rotating disk 21 and ensuring its smooth rotation.

[0048] See also Figure 1As shown, the outer circumferential wall of the rotating disk 21 has a plurality of drive teeth arranged along its circumference. The rotating drive member 22 is connected to the volute 11 and is arranged adjacent to the rotating disk 21. The rotating drive member 22 includes a runner 221, which meshes with the drive teeth. The runner 221 is drivingly connected to the output shaft of the corresponding rotating motor. After the rotating motor receives the operation signal, it drives the runner 221 to rotate a certain angle, thereby driving the rotating disk 21 to produce a position change, realizing the switching between the conduction and interception of the internal circulation. The aforementioned rotating motor can be installed on the diffuser panel 13. The operation signal of the aforementioned rotating motor can come from a command triggered by manual selection, or it can be a sensor that detects the flow rate of the air outlet of the volute 11. When the detected flow rate is lower than a preset value, the aforementioned command is automatically issued.

[0049] The following further illustrates the technical solution of the present invention by taking the fluid as air flow, especially refrigerant air flow as an example:

[0050] See also Figure 2 As shown, the centrifugal compressor involved in the present invention objectively includes a main airflow system and an internal circulation system, wherein the airflow direction of the main airflow system is: air intake 141 - impeller flow channel - diffuser flow channel - volute flow channel; Figure 3 As shown, the air flow direction of the internal circulation system is: diffuser flow channel-internal circulation inlet flow channel-gas collecting volute flow channel (that is, the aforementioned collecting chamber 144, the same below)-internal circulation throttling flow channel (that is, the aforementioned throttling section 143, the same below)-intake port 141.

[0051] like Figure 3 As shown, the principle of widening the operating range of the centrifugal compressor involved in the present invention is: when the air flow enters from the air intake, after passing through the impeller 12 and the diffuser (that is, the aforementioned diffuser panel 13, the same below), a part of the air flow is diverted from the diffuser into the internal circulation system, and after being throttled and reduced in pressure by the internal circulation system, it enters the air intake 141 again. The internal circulation system can effectively divert the flow of the main air flow, thereby effectively controlling the flow of the air flow out of the volute 11; the centrifugal compressor involved in the present invention is mainly used to widen the operating range of the centrifugal compressor, especially to solve the problem that the compressor is prone to surge at low load (low flow). When the flow load at the compressor volute outlet is low, the internal circulation system is opened; under the condition that the impeller 12 can operate normally, the flow at the outlet of the volute 11 is reduced, and a part of it enters the internal circulation system for internal circulation. Its path is as described above, diffuser flow channel-internal circulation inlet flow channel-gas collecting volute flow channel-internal circulation throttling flow channel-intake port 141.

[0052] According to an embodiment of the present invention, there is further provided an air conditioner comprising the above-mentioned centrifugal compressor.

[0053] It is easy for those skilled in the art to understand that, under the premise of no conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0054] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art may make various improvements and variations without departing from the technical principles of the present invention, and such improvements and variations shall also be considered within the scope of protection of the present invention.

Claims

1. A centrifugal compressor, characterized in that: include: A volute (11), wherein an impeller (12) is provided in the volute (11); A diffuser panel (13) forms an outflow channel (111) with the volute (11); An air suction hood (14) is located on the air suction side of the impeller (12), and the air suction hood (14) has an air suction port (141) and an internal circulation air supply port (142) connected to the air suction port (141); The fluid in the outlet flow channel (111) can be controlled to communicate with the internal circulation air supply port (142); the air intake hood (14) is constructed with an internal circulation flow channel that is connected to the internal circulation air supply port (142) and is controllably connected to the outlet flow channel (111); the internal circulation flow channel includes a throttling section (143) that is connected to the internal circulation air supply port (142); the internal circulation flow channel also includes a collecting chamber (144) arranged around the air intake port (141), the internal circulation air supply port (142) has a plurality of, and the plurality of internal circulation air supply ports (142) are evenly spaced around the air intake port (141), the throttling sections (143) have a plurality of, and the plurality of throttling sections (143) are arranged one-to-one with the plurality of internal circulation air supply ports (142), and the plurality of throttling sections (143) surround the collecting chamber. The cavities (144) are evenly spaced, and the throttling section (143) is connected between the collecting cavity (144) and the internal circulation air supply port (142); it also includes an on-off control component, the diffuser panel (13) is constructed with a flow hole (131) connected to the outflow channel (111), and the on-off control component can control the on-off between the flow hole (131) and the collecting cavity (144); the on-off control component includes a rotating disk (21) and a rotating drive member (22) for driving the rotating disk (21) to rotate, the rotating disk (21) is mounted on the diffuser panel (13), and the rotating disk (21) has an on-off component, and during the rotation of the rotating disk (21), the on-off component can make the flow hole (131) and the collecting cavity (144) conductive or cut off.

2. The centrifugal compressor according to claim 1, characterized in that The on-off assembly comprises a sealing ball (231) and an elastic member (232) that applies elastic force to the sealing ball (231) on a side away from the through-hole (131), wherein the sealing ball (231) has an off state in which it is partially inside the through-hole (131) and an on state in which it is outside the through-hole (131); and / or, the rotating disk (21) is fitted with the diffuser panel (13) via a sliding bearing (24).

3. The centrifugal compressor according to claim 2, characterized in that There are a plurality of through-flow holes (131), and the plurality of through-flow holes (131) are evenly spaced around the pressure diffuser panel (13). There are a plurality of on-off components, and the plurality of on-off components are arranged in a one-to-one correspondence with the plurality of through-flow holes (131).

4. The centrifugal compressor according to claim 3, characterized in that The area between two adjacent on-off components is a first area, and a flow groove (211) is constructed on the rotating disk (21) corresponding to the first area, and the flow groove (211) communicates with the flow hole (131) and the manifold (144).

5. The centrifugal compressor according to claim 1, wherein: The outer circumferential wall of the rotating disk (21) is provided with a plurality of driving teeth arranged along its circumference. The rotating driving member (22) is connected to the volute (11) and is arranged adjacent to the rotating disk (21). The rotating driving member (22) includes a rotating wheel (221) that is engaged with the driving teeth.

6. An air conditioner, characterized in that: A centrifugal compressor comprising the centrifugal compressor according to any one of claims 1 to 5.

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