Centrifugal impeller, compressor, air conditioner and manufacturing method of centrifugal impeller

Abstract

This disclosure relates to a centrifugal impeller, a compressor, an air conditioner, and a centrifugal impeller control method. The centrifugal impeller includes a hub, a cover, and multiple blades. Each blade includes a sequentially arranged intake section, a transition section, and a supplementary air section. The intake section is configured to allow a first gas to flow from the leading edge of the intake section to the trailing edge of the intake section as the hub rotates, thereby performing primary compression on the first gas. The leading edge of the supplementary air section is connected to the trailing edge of the intake section via the transition section, so that a second gas drawn in from the supplementary air channel mixes with the first gas after primary compression via the transition section to form a mixed gas. The supplementary air section is configured to allow the mixed gas to flow from the leading edge of the supplementary air section to the trailing edge of the supplementary air section as the hub rotates, thereby performing secondary compression on the mixed gas.

Description

Technical Field

[0001] This disclosure relates to the field of compressors, and more particularly to a centrifugal impeller, a compressor, an air conditioner, and a method for manufacturing the centrifugal impeller. Background Technology

[0002] The centrifugal impeller is a key component of a centrifugal compressor. When the impeller rotates at high speed, it generates centrifugal force, which draws gas into the center of the impeller and moves it along the channel formed between the blades. By designing different blade structures, the speed and pressure characteristics of the gas leaving the impeller can be controlled.

[0003] For applications requiring high pressure ratios, single-stage compression is often insufficient, necessitating multi-stage compression. Related technologies employ supplementary air blades between adjacent intake blades to achieve enthalpy enhancement and multi-stage compression within a single impeller. However, in this method, the intake and supplementary air blades are independent and discontinuous. When the airflow encounters such sudden changes in cross-section or direction, fluid separation can easily occur, leading to unstable gas flow, increased flow losses and pressure fluctuations, and a higher risk of blade cracking due to localized stress concentration. Summary of the Invention

[0004] In view of this, the present disclosure provides a centrifugal impeller, a compressor, an air conditioner, and a method for manufacturing a centrifugal impeller, which helps to improve operational stability.

[0005] In one aspect of this disclosure, a centrifugal impeller is provided, comprising:

[0006] The hub is rotatably mounted about its axis;

[0007] A wheel cover is fitted onto the outside of the wheel hub. The wheel cover includes an intake wheel cover and an air replenishment wheel cover that are arranged radially at intervals. The intake wheel cover has an intake port for intake of a first gas, and an air replenishment channel for intake of a second gas is formed between the intake wheel cover and the air replenishment wheel cover.

[0008] Multiple blades, each blade comprising an intake section, a transition section, and a supplementary air section arranged sequentially.

[0009] The intake section is located between the hub and the intake cover along the axial direction of the hub, and is configured to allow the first gas to flow from the leading edge of the intake section to the trailing edge of the intake section as the hub rotates, so as to perform primary compression of the first gas.

[0010] The leading edge of the supplementary gas section and the trailing edge of the intake section are connected by a transition section so that the second gas drawn in from the supplementary gas channel can be mixed with the first gas after primary compression through the transition section to form a mixed gas.

[0011] The air injection section is located axially between the hub and the air injection cover, and is configured to allow the gas mixture to flow from the leading edge to the trailing edge of the air injection section as the hub rotates, so as to perform secondary compression of the gas mixture.

[0012] In some embodiments, the transition section is tangentially connected to the intake section and the replenishment section by circular arcs.

[0013] In some embodiments, the transition section includes a first arc portion tangent to the rear edge of the intake section and a second arc portion tangent to the front edge of the supplemental air section, the first arc portion and the second arc portion being tangentially connected.

[0014] In some embodiments, on the vertical projection through the center of the hub, the center of the first arc portion is located at a first point, the center of the second arc portion is located at a second point, and the distance between the first point and the second point along the radial direction of the hub is a first distance.

[0015] The radii of the first and second circular arcs are related to the first distance.

[0016] In some embodiments, the width of the air supply channel along the radial direction of the hub is a second distance;

[0017] The first distance is related to the second distance.

[0018] In some embodiments, the first distance is 2 to 2.5 times the second distance.

[0019] In some embodiments, the radius of the first arc portion is equal to the radius of the second arc portion.

[0020] In some embodiments, the first arc portion and the second arc portion are tangent to the fifth point, the fifth point is respectively the third distance between the profile of the air replenishment section and the profile of the air intake section, and the distance between the profile of the air replenishment section and the profile of the air intake section is the fourth distance.

[0021] The radii of the first and second circular arcs are related to the ratios of the third and fourth distances.

[0022] In some embodiments, the ratio of the third distance to the fourth distance is 10%-12%.

[0023] In some embodiments, the flow area of ​​the gas replenishment channel is related to the flow rate ratio of the second gas to the first gas.

[0024] In some embodiments, on the vertical projection through the center of the hub, the width of the air supply channel along the radial direction of the hub is the second distance, and the distance between the profile of the air supply section and the profile of the intake section is the fourth distance.

[0025] The second distance and / or the fourth distance are related to the flow ratio of the second gas and the first gas.

[0026] In some embodiments, the flow rate ratio of the second gas to the first gas is 8 to 13%.

[0027] In some embodiments, on the vertical projection through the center of the hub, the center of the second arc portion of the width of the air supply channel along the radial direction of the hub is located at a second point, and the second point is located on the extension line of the inner wall of the air supply channel near the side of the air supply wheel cover.

[0028] In another aspect of this disclosure, a compressor is provided, including a centrifugal impeller as described above.

[0029] In another aspect of this disclosure, an air conditioner is provided, including the compressor as described above.

[0030] In another aspect of this invention, a method for manufacturing a centrifugal impeller based on any of the above-described centrifugal impellers is provided, comprising:

[0031] The wheel cover is welded to the tip of the blade;

[0032] An air supply channel is made in the wheel cover;

[0033] Among them, the intake wheel cover and the replenishment wheel cover are connected by an arc before the air replenishment channel is opened.

[0034] In some embodiments, the operation of opening an air supply channel on the wheel cover specifically includes:

[0035] During the process of opening the air supply channel on the wheel cover, the solder accumulated during the welding of the wheel cover and the blade tip is removed.

[0036] Therefore, according to the embodiments of this disclosure, the integrated blades can avoid fluid separation caused by sudden changes in cross-section or abrupt changes in direction of the airflow. The transition section connecting the intake section and the supplementary air section can make the flow field transition smoothly, form a more uniform flow field, reduce fluid separation, make the centrifugal impeller run more stably, and facilitate processing, manufacturing and actual production. Attached Figure Description

[0037] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0038] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:

[0039] Figure 1 This is a cross-sectional view of some embodiments of the centrifugal impeller according to the present disclosure;

[0040] Figure 2 This is a cross-sectional view of some other embodiments of the centrifugal impeller according to the present disclosure;

[0041] Figure 3 yes Figure 1 A partial schematic diagram of region F in the middle;

[0042] Figure 4 These are partial schematic diagrams of other embodiments of the centrifugal impeller according to the present disclosure;

[0043] Figure 5 This is a schematic diagram of the structure of some embodiments of the blades and hub of the centrifugal impeller according to the present disclosure;

[0044] Figure 6 This is a cross-sectional view of some embodiments of the blades and hub of the centrifugal impeller according to the present disclosure;

[0045] Figure 7 This is a partial schematic diagram of the transition section of the centrifugal impeller according to this disclosure;

[0046] Figure 8 This is a flowchart of some embodiments of the centrifugal impeller manufacturing method according to the present disclosure.

[0047] In the picture:

[0048] 1. Wheel hub;

[0049] 2. Wheel cover; 21. Intake wheel cover; 211. Intake port; 22. Air supply wheel cover; 23. Air supply channel;

[0050] 3. Blades; 31. Intake section; 32. Transition section; 321. First arc section; 322. Second arc section; 33. Air supply section;

[0051] A. First point; B. Second point; C. Third point; D. Fourth point; E. Fifth point;

[0052] X1, first distance; X2, second distance; X4, fourth distance;

[0053] L1, the profile of the intake blade; L2, the profile of the supplementary air blade.

[0054] It should be understood that the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Furthermore, the same or similar reference numerals denote the same or similar components. Detailed Implementation

[0055] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the present disclosure or its application or use. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that the present disclosure will be thorough and complete, and will fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless specifically stated otherwise, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0056] The terms "first," "second," and similar words used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "contains" mean that the element preceding the word encompasses the element listed after it, and do not exclude the possibility of encompassing other elements as well. Terms such as "above," "below," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, this relative positional relationship may also change accordingly.

[0057] In this disclosure, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.

[0058] All terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0059] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0060] Between adjacent compression stages, the gas exiting the previous stage must first pass through an intercooler to cool its temperature to near its initial temperature before entering the next stage impeller for further compression. However, more components mean higher manufacturing and installation costs as well as subsequent maintenance costs. This approach typically leads to a more complex compressor structure, increased friction and mechanical losses, and a narrower operating range for the compressor due to multi-stage compression.

[0061] In related technologies, supplementary air blades are set between two adjacent intake blades to achieve intermediate air supplementation and enthalpy increase and multi-stage compression in a single impeller. In this method, the intake and supplementary air blades are independent and discontinuous blades.

[0062] Because fluid flow is affected by pressure distribution, if there are abrupt changes on the blade surface, a reverse pressure gradient can easily be generated when the fluid passes over it. This means that the pressure gradually increases along the flow direction, causing the fluid velocity to gradually decrease and its kinetic energy to diminish, making it difficult for the fluid to maintain adhesion within the boundary layer. When the reverse pressure gradient is too large, the boundary layer will detach from the wall, forming a separation zone.

[0063] In related technologies, when the airflow encounters such a sudden change in cross-section or direction between discontinuously arranged intake and replenishment blades, fluid separation is likely to occur, leading to unstable gas flow, increased flow loss and pressure fluctuations, difficulty in uniformly mixing replenishment and outlet gas, failure to achieve the design pressure ratio when the gas is discharged through the replenishment channel, and easy for the blades to crack due to local stress concentration.

[0064] The processing of two discontinuous blade sections also presents many challenges, such as the difficulty in welding the impeller cover and the blade, which may lead to blade cracking or weld buildup at the joint, affecting impeller efficiency.

[0065] In view of this, in one aspect of the present disclosure, a centrifugal impeller is provided that can improve operational stability.

[0066] Figure 1 These are cross-sectional views of some embodiments of the centrifugal impeller according to this disclosure. Figure 2 This is a cross-sectional view of some other embodiments of the centrifugal impeller according to the present disclosure. Figure 3 yes Figure 1 A partial schematic diagram of region F in the middle. In the diagram, the X direction is parallel to the axis of hub 1, and the Y direction is parallel to the radial direction of the hub. (Reference) Figures 1-3 The centrifugal impeller includes a hub 1, a cover 2, and multiple blades 3.

[0067] The hub 1 is shaped like a frustum of a cone, with multiple blades 3 disposed on its circumferential side surfaces. The hub 1 has an upper end face and a lower end face parallel to the axial direction, both of which are perpendicular to the axis of the hub 1. The hub 1 is rotatably mounted about its central axis.

[0068] Wheel cover 2 is fitted on the outside of wheel hub 1. Wheel cover 2 includes an intake wheel cover 21 and an air replenishment wheel cover 22 arranged radially at intervals. The intake wheel cover 21 has an intake port 211 for intake of a first gas. The annular gap between the intake wheel cover 21 and the air replenishment wheel cover 22 forms an air replenishment channel 23 for intake of a second gas.

[0069] Each blade 3 includes an intake section 31, a transition section 32, and an air replenishment section 33 arranged sequentially, and each blade 3 is an integral structure. The intake section 31 is closer to the center of the hub 1 than the air replenishment section 33. Multiple blades 3 are circumferentially evenly distributed on the circumferential side of the hub 1, forming multiple axially evenly distributed compression channels.

[0070] The intake section 31 is disposed along the axial direction of the hub 1 between the hub 1 and the intake cover 21, and is configured to allow the first gas to flow from the leading edge of the intake section 31 to the trailing edge of the intake section 31 as the hub 1 rotates, so as to perform primary compression of the first gas.

[0071] The leading edge of the supplementary gas section 33 and the trailing edge of the intake section 31 are connected by a transition section 32, so that the second gas drawn in from the supplementary gas channel 23 is mixed with the first gas after primary compression through the transition section 32 to form a mixed gas. The transition section 32 is configured to provide a smooth flow field transition between the supplementary gas section 33 and the intake section 31, reduce fluid separation on the blade surface, reduce vibration, and make the gas flow more stable.

[0072] The supplementary air section 33 is disposed axially between the hub 1 and the supplementary air cover 22 along the hub 1. It is configured to allow the mixed gas to flow from the leading edge to the trailing edge of the supplementary air section 33 as the hub 1 rotates, so as to perform secondary compression of the mixed gas. The supplementary air section 33 is designed based on the outlet state of the first gas in the intake section 31 and the final required pressure ratio.

[0073] During the rotation of hub 1, a primary compression channel is formed between adjacent intake sections 31, and a secondary compression channel is formed between adjacent supplementary intake sections 33. Each primary compression channel corresponds to a unique secondary compression channel. After the first gas completes primary compression in the primary compression channel, it mixes with the second gas at the transition section 32, causing the overall temperature of the mixture to decrease. The mixture then completes secondary compression in the secondary compression channel and is discharged from the impeller. Upon discharge, the secondary compressed mixture reaches the design pressure ratio.

[0074] The leading edge of the intake section 31 is closer to the upper surface of the hub 1 than the trailing edge of the intake section 31, the leading edge of the intake section 31 is closer to the center of the hub 1 than the trailing edge of the intake section 31, and the trailing edge of the intake section 31 is closer to the lower surface of the hub 1 than the leading edge of the intake section 31.

[0075] Each intake section 31 is configured such that its leading edge is closer to the rear side of the rotation direction of the hub 1 than its trailing edge, and the curled arrangement of the intake section 31 gives it a pressure surface facing downstream of the rotation direction and a suction surface facing upstream of the rotation direction.

[0076] The leading edge of the air inlet section 33 is closer to the upper surface of the wheel hub 1 than the trailing edge of the air inlet section 33. The trailing edge of the air inlet section 33 is closer to the outer edge of the wheel hub 1 than the leading edge of the air inlet section 33. The trailing edge of the air inlet section 33 is closer to the lower surface of the wheel hub 1 than the leading edge of the air inlet section 33.

[0077] Each air supply section 33 is configured such that its leading edge is closer to the rear side of the rotation direction of the hub 1 than its trailing edge, and the curled arrangement of the air supply section 33 gives it a pressure surface facing downstream of the rotation direction and a suction surface facing upstream of the rotation direction.

[0078] The lower edge of the blade 3 connecting to the circumferential side of the hub 1 is defined as the blade root, and the upper edge of the blade 3 away from the circumferential side of the hub 1 is defined as the blade tip. The blade root of the blade 3 can be fixedly connected to the circumferential side of the hub 1 by welding, gluing, snap-fitting, riveting, or other methods. The blade tip of the blade 3 can be fixedly connected to the wheel cover 2 by welding, gluing, snap-fitting, riveting, or other methods.

[0079] The intake wheel cover 21 and the supplementary air wheel cover 22 are respectively provided with transition parts that match the transition section 32, so that the inner surfaces of the intake wheel cover 21 and the supplementary air wheel cover 22 are completely in contact with the blade tip of the blade 3.

[0080] By setting a single blade 3 of a single centrifugal impeller to have an intake section 31 and an air replenishment section 33, and combining the intake impeller cover 21 and the air replenishment impeller cover 22 to form an air replenishment channel 23, the single impeller has a two-stage compression function, which can meet the high pressure ratio requirement, and air replenishment and enthalpy increase are carried out in the middle of the single impeller, effectively improving the aerodynamic efficiency of the impeller.

[0081] Improved aerodynamic efficiency also reduces energy loss. Centrifugal impellers can perform more useful work under the same operating conditions, thus improving the overall efficiency of the compressor and enabling it to operate at a higher efficiency. This enhances the overall performance of the compressor, increases its pressure ratio, and effectively reduces the number of stages in the compressor.

[0082] Compared to related technologies where the air supply blades and intake blades are set as independent and discontinuous blades, the integrated blade 3 in this embodiment can avoid fluid separation caused by sudden changes in cross-section or direction of airflow. The transition section 32, which connects the intake section 31 and the air supply section 33, can provide a smooth flow field transition, form a more uniform flow field, reduce fluid separation, make the centrifugal impeller run more stably, and facilitate processing, manufacturing and actual production.

[0083] Figure 4 These are partial schematic diagrams of other embodiments of the centrifugal impeller according to the present disclosure. Figure 5 These are schematic diagrams illustrating the structure of some embodiments of the blades and hub of the centrifugal impeller according to this disclosure. Figure 6These are cross-sectional views of some embodiments of the blades and hub of the centrifugal impeller according to this disclosure. Figure 7 This is a partial schematic diagram of the transition section of the centrifugal impeller according to the present disclosure. Figure 4 Point M in the diagram is the intersection of the air intake cover 22 and the leading edge of the air intake section 33. Figure 4 Point N is the intersection of the intake wheel cover 21 and the rear edge of the intake section 31. The transition section 32 is located between point M and point N. Figure 6 The dashed line passing through point E is the transition segment 32.

[0084] refer to Figure 1 , Figures 3-7 In some embodiments, the transition section 32 is tangentially connected to the intake section 31 and the supplementary air section 33 by circular arcs.

[0085] The transition section 32 and the intake section 31 are connected tangentially by an arc at their intersection points, and the transition section 32 and the supplementary air section 33 are connected tangentially by an arc at their intersection points. The two intersection points are connected by, but are not limited to, a straight line or an arc.

[0086] Because fluid flow is affected by pressure distribution, if there are abrupt changes on the blade surface, a reverse pressure gradient can easily be generated when the fluid passes over it. This means that the pressure gradually increases along the flow direction, causing the fluid velocity to gradually decrease and its kinetic energy to diminish, making it difficult for the fluid to maintain adhesion within the boundary layer. When the reverse pressure gradient is too large, the boundary layer will detach from the wall, forming a separation zone.

[0087] In this embodiment, the transition section 32 is connected to the intake section 31 and the supplementary air section 33 by tangent circular arcs, which can smoothly change the flow direction and pressure distribution of the fluid, making the adverse pressure gradient smaller and more uniform, thereby delaying or even avoiding boundary layer separation. It provides a smooth transition channel between the intake section 31 and the supplementary air section 33, so that the airflow can flow smoothly from the primary compression channel to the secondary compression channel, making the pressure distribution in the channel more uniform, reducing flow instability, reducing the local pressure loss borne by the blade 3, and reducing the risk of root breakage of the blade 3.

[0088] Figure 3 , Figure 4 and Figure 7 L1 and L2 in the text are the original profile lines of blade 3. Figure 3 , Figure 4 and Figure 7 The solid line portion of L1 represents the intake section 31. Figure 3 , Figure 7 The dashed part of L1 is the intake part in the original shape line of the blade 3 before the transition section 32 is set. This intake part has deviated from the transition section 32. Figure 3 , Figure 4 The fourth point D is located at the trailing edge of the intake section in the original profile of blade 3.

[0089] Figure 3 , Figure 4 and Figure 7 The solid line portion of L2 represents the air intake section 33. Figure 3 , Figure 4 and Figure 7 The dashed part of L2 is the air replenishment part in the original shape line before the transition section 32 is set on the blade 3. This air replenishment part has deviated from the transition section 32. Figure 3 , Figure 4 The third point C is located at the leading edge of the air intake section in the original shape of blade 3.

[0090] refer to Figure 1 , Figures 3-7 In some embodiments, the transition section 32 includes a first arcuate portion 321 tangent to the rear edge of the intake section 31 and a second arcuate portion 322 tangent to the front edge of the supplementary air section 33, wherein the first arcuate portion 321 and the second arcuate portion 322 are tangentially connected.

[0091] Correspondingly, before the air supply channel 23 is opened, the intake wheel cover 21 and the air supply wheel cover 22 are also connected by two tangent arcs corresponding to the first arc portion 321 and the second arc portion 322.

[0092] The first arc portion 321 includes, but is not limited to, convex relative to the lower end surface of the hub 1 in the direction from the upper end surface to the lower end surface, and the second arc portion 322 includes, but is not limited to, concave relative to the lower end surface of the hub 1 in the direction from the upper end surface to the lower end surface. After the wheel cover 2 and the blade 3 are welded, the first arc portion 321 and the second arc portion 322 will also form a tangential connection along the thickness direction of the blade 3.

[0093] If the transition section 32 only includes a single arc segment, it will result in uneven distortion points at the end connecting to the supplementary air section 33 or the intake section 31. Furthermore, to make the connection between the supplementary air section 33 and the intake section 31 smoother, the radius of the arc segment needs to be larger, causing the blade 3 to deviate too much from the design profile, reducing impeller efficiency, and preventing the gas discharged through the supplementary air channel from reaching the design pressure ratio.

[0094] In this embodiment, the transition section 32 includes a tangent first arc portion 321 and a second arc portion 322, which can provide a smoother flow field transition between the air supply section 33 and the air intake section 31, gently changing the flow direction and pressure distribution of the fluid, making the reverse pressure gradient smaller and more uniform, thereby delaying or even avoiding boundary layer separation, reducing fluid separation on the blade surface, reducing vibration level, making the pressure distribution more uniform, improving flow stability, and helping to improve the service life of the blades and the operating stability of the compressor.

[0095] refer to Figure 3In some embodiments, on the vertical projection through the center of the hub 1, the center of the first arc portion 321 is located at a first point A, and the center of the second arc portion 322 is located at a second point B. The radial distance between the first point A and the second point B along the hub 1 is a first distance X1. The radii of the first arc portion 321 and the second arc portion 322 are related to the first distance X1.

[0096] The radii of the first arc portion 321 and the second arc portion 322 are limited by the first distance X1, and the value of the first distance X1 determines the value of the radius of the first arc portion 321 and the second arc portion 322.

[0097] When the radii of the first arc portion 321 and the second arc portion 322 are small, they are close to being connected between the intake section 31 and the replenishment section 33 by a straight line. At this time, the curvature of the first arc portion 321 and the second arc portion 322 is too large, and the connection is not smooth. This causes abrupt changes and instability in the transition section 32, and fluid separation is still likely to occur, making it impossible to achieve a smooth transition.

[0098] When the radius of the first arc portion 321 and the second arc portion 322 is larger, the transition between the intake section 31 and the supplementary air section 33 is smoother, but this will cause the transition section 32 of the blade 3 to deviate more from the original design profile of the blade 3, resulting in a decrease in the aerodynamic efficiency of the impeller.

[0099] In this embodiment, by adjusting the first distance X1 between the first point A and the second point B along the radial direction of the hub 1, the radii of the first arc portion 321 and the second arc portion 322 can achieve a smoother arc transition as much as possible while deviating less from the original profile of the blade 3, so that the centrifugal impeller has better compression performance and operational stability.

[0100] refer to Figure 3 In some embodiments, on the vertical projection through the center of the hub 1, the width of the air supply channel 23 along the radial direction of the hub 1 is a second distance X2. The width of the air supply channel 23 includes, but is not limited to, being equal to the width of the third point C and the fourth point D. Figure 3 The radial distance in the equation. The first distance X1 is related to the second distance X2.

[0101] When the width of the gas supply channel 23 is large, more second gas can be supplied. Therefore, more space needs to be provided for the second gas to meet the needs of its entry and mixing. Thus, the transition section 32 needs to have a larger size, which requires the first distance X1 to be set larger.

[0102] In this embodiment, by making the first distance X1 related to the width of the gas replenishment channel 23, the first distance X1 can be adaptively adjusted according to the flow rate of the replenished gas, thereby enabling the replenished second gas to flow and mix smoothly in the transition section 32, so as to improve the gas flow stability.

[0103] refer to Figure 3 The first distance X1 is 2 to 2.5 times the second distance X2.

[0104] If the first distance X1 and the second distance X2 are equal, the radii of the first arc portion 321 and the second arc portion 322 are small and the radii of curvature are large, which is close to a straight line connecting the intake section 31 and the supplementary air section 33. This will result in an uneven connection between the intake section 31 and the supplementary air section 33. The second gas supplied by the supplementary air channel 23 and the first gas compressed by the intake section 31 may experience fluid separation at the connection point. This increases turbulence in the gas flow, leading to unstable gas flow, increased flow losses and pressure fluctuations. When the mixed gas is discharged after secondary compression, it cannot reach the design pressure ratio. Furthermore, the uneven connection point can cause local stress concentration in the blade 3, increasing the risk of root fracture of the blade 3.

[0105] The first distance X1 is small, which makes it inconvenient to process the transition section 32. In addition, during welding, because the first distance X1 is small, the solder will not only fill the second arc portion 322, but also overflow downwards to the air supply section 33. When the air supply channel 23 is opened on the wheel cover 2, it is difficult to clean the solder that overflows into the air supply section 33 area. Therefore, it is impossible to remove the overflowing solder, and because the area is small, it is also difficult to clean it manually.

[0106] In this embodiment, the first distance X1 is selected as 2 to 2.5 times the second distance X2, including but not limited to 2 times. This can provide a sufficiently smooth flow field transition in the transition section 32 and achieve minimal deviation relative to the profile of the blade 3. While ensuring the compression efficiency of the intake section 31 and the supplementary air section 33, the flow stability is improved, the abrupt changes between the intake section 31 and the supplementary air section 33 are reduced, and the risk of blade 3 cracking is reduced.

[0107] refer to Figure 3 and Figure 6 In some embodiments, the radius of the first arc portion 321 is equal to the radius of the second arc portion 322.

[0108] In this embodiment, by setting the first arc portion 321 and the second arc portion 322 to have equal radii, the first arc portion 321 and the second arc portion 322 can achieve a larger radius within the range of possible values ​​to the same extent, thereby achieving a smoother transition.

[0109] refer to Figure 7In some embodiments, the first arc portion 321 and the second arc portion 322 are tangent to a fifth point E. The distance between the fifth point E and the profiles of the air supply section 33 and the air intake section 31 is a third distance, and the distance between the profile L2 of the air supply section 33 and the profile L1 of the air intake section 31 is a fourth distance X4. The radii of the first arc portion 321 and the second arc portion 322 are related to the ratio of the third distance to the fourth distance X4.

[0110] The third distance is the distance between the fifth point E in actual three-dimensional space and the profile L2 of the supplementary air section 33, and the distance between the fifth point E in actual three-dimensional space and the profile L1 of the intake section 31. Figure 7 Not shown in the diagram. The third distance is the distance between the profile lines of the eccentric blade 3 in the transition section 32.

[0111] When the fourth distance X4 between the profile L2 of the supplementary air section 33 and the profile L1 of the intake section 31 is constant, the smaller the ratio of the third distance to the fourth distance X4, the smaller the radius of the first arc portion 321 and the second arc portion 322, the greater the flow instability at the arc connection between the intake section 31 and the supplementary air section 33, making it difficult to achieve a smooth transition. The larger the ratio of the third distance to the fourth distance X4, the larger the radius of the first arc portion 321 and the second arc portion 322, and the smoother the transition, but the more it deviates from the blade design profile, and the lower the impeller efficiency.

[0112] In this embodiment, by controlling the ratio of the third distance to the fourth distance X4, the radii of the first arc portion 321 and the second arc portion 322 can achieve a smoother arc transition as much as possible while deviating less from the original profile of the blade 3. This improves flow stability while ensuring the compression efficiency of the intake section 31 and the supplementary air section 33, reduces abrupt changes between the intake section 31 and the supplementary air section 33, and gives the centrifugal impeller better compression performance and operational stability.

[0113] In some embodiments, the ratio of the third distance to the fourth distance X4 is 10%-12%.

[0114] In this embodiment, the ratio of the third distance to the fourth distance X4 is selected as 10%-12%, which enables the transition section 32 to provide a sufficiently smooth flow field transition, improve flow stability, and achieve minimal deviation relative to the profile of the blade 3, so that the impeller can achieve the preset pressure ratio.

[0115] In some embodiments, the flow area of ​​the supplementary gas channel 23 is related to the flow ratio of the second gas and the first gas. If the flow rate of the second gas is too high, while the flow area of ​​the supplementary gas channel 23 remains unchanged, the excessive flow velocity of the second gas will lead to uneven mixing with the compressed first gas, thereby affecting the compression performance and stability. Therefore, it is necessary to ensure that the flow area of ​​the supplementary gas channel 23 is in harmony with the proportion of the second gas.

[0116] In this embodiment, the flow area of ​​the gas replenishment channel 23 determines the flow rate of the second gas that can be replenished. By controlling the flow area of ​​the gas replenishment channel 23 to adapt to the flow ratio of the replenished second gas and the first gas, it helps to make the first gas and the second gas mix more evenly, improve the compression performance of the centrifugal impeller, and reduce the processing cost of the centrifugal impeller as much as possible.

[0117] refer to Figure 3 In some embodiments, on the vertical projection through the center of the hub 1, the width of the air supply channel 23 along the radial direction of the hub 1 is a second distance X2, and the distance between the profile of the air supply section 33 and the profile of the intake section 31 is a fourth distance X4. The second distance X2 and / or the fourth distance X4 are related to the flow rate ratio of the second gas and the first gas.

[0118] When the required flow rate of the second gas is larger, the second distance X2 and / or the fourth distance X4 need to be set larger in order to provide a larger flow area for the second gas and the mixed gas.

[0119] In this embodiment, by adaptively varying the second distance X2 and / or the fourth distance X4 with the flow ratio of the second gas and the first gas, the second gas and the mixed gas can flow more smoothly and be more rationally distributed in the secondary compression channel, thereby improving the aerodynamic efficiency of the centrifugal impeller, optimizing the compression performance, and increasing the compression ratio.

[0120] In some embodiments, the flow rate ratio of the second gas to the first gas is 8 to 13%, including but not limited to 10%.

[0121] In this embodiment, when the flow ratio of the second gas to the first gas is 8-13%, the second gas can be fully mixed with the first gas after primary compression, and the added second gas can effectively cool the first gas after primary compression, so as to improve the compression efficiency of the impeller.

[0122] refer to Figure 3 In some embodiments, on the vertical projection through the center of the hub 1, the center of the second arc portion 322 is located at a second point B, which is located on the extension line of the inner wall of the air supply channel 23 near the air supply cover 22.

[0123] During the manufacturing process, the wheel cover 2 is connected to the blade 3 by welding. The solder is poured in from the connection between the blade 3 and the hub 1. As it flows from top to bottom, the solder tends to accumulate in areas with greater curvature.

[0124] For the transition section 32, when the first arc portion 321 bulges in the direction from the upper end face to the lower end face along the hub 1 and the second arc portion 322 is concave in the direction from the upper end face to the lower end face along the hub 1, solder will accumulate at the second arc portion 322, and the curvature at the second point B is the largest, and the solder accumulation is the most serious.

[0125] By setting the second point B on the extension line of the inner wall of the air supply channel 23 near the air supply wheel cover 22, the inner wall of the air supply channel is aligned with the center of the second arc portion 322. When the air supply channel 23 is slotted, the wheel cover 2 is chiseled through, and the solder accumulated at the second arc portion 322 during the welding of the wheel cover 2 and the blade 3 can be removed and taken away.

[0126] In this embodiment, by aligning the opening sidewall of the gas supply channel 23 with the center of the second arc portion 322, as much solder accumulated during welding can be removed as much as possible, ensuring that the gas has sufficient flow area and reducing the impact of solder accumulation on airflow.

[0127] In another aspect of the present disclosure, a compressor is provided, including a centrifugal impeller as described in any of the above embodiments, the compressor being suitable for applications requiring a high pressure ratio.

[0128] By using this centrifugal impeller, two-stage compression can be achieved with a single centrifugal impeller, which can significantly improve the performance of the compressor. Furthermore, based on the improvement of the centrifugal impeller's aerodynamic efficiency, energy loss can also be reduced. The centrifugal impeller can do more useful work under the same operating conditions, thereby improving the overall efficiency of the compressor and enabling it to work in a more efficient state. This improves the overall performance of the compressor, increases the compressor's pressure ratio, and can effectively reduce the number of stages in the compressor.

[0129] In this embodiment, the blades 3 of the centrifugal impeller can prevent fluid separation caused by sudden changes in cross-section or direction of airflow. The transition section 32, which connects the intake section 31 and the supplementary section 33, can make the flow field transition smoothly, form a more uniform flow field, reduce fluid separation, make the compressor run more stably, and facilitate processing, manufacturing and actual production.

[0130] In another aspect of the present disclosure, an air conditioner is provided, including a compressor as described in the above embodiments, the compressor being disposed in the outdoor unit of the air conditioner.

[0131] In this embodiment, the air conditioner can achieve high operating efficiency and stability, and is easy to process, manufacture and actual production.

[0132] Figure 8 This is a flowchart of some embodiments of the centrifugal impeller manufacturing method according to the present disclosure, with reference to... Figure 8In another aspect of this disclosure, a method for manufacturing a centrifugal impeller based on any of the above embodiments is provided, comprising steps S1 to S2:

[0133] In step S1, the wheel cover 2 is welded to the tip of the blade 3. After the wheel cover 2 and the blade 3 are welded, the inner surface of the wheel cover 2 is completely in contact with the tip of the blade 3.

[0134] In step S2, an air supply channel 23 is opened on the wheel cover 2. The depth of the air supply channel 23 along the axial direction of the hub 1 can match the thickness of the wheel cover 2 along the axial direction of the hub. During the opening of the air supply channel 23, the wheel cover 2 is chiseled to divide the wheel cover 2 into an intake wheel cover 21 and an air supply wheel cover 22 so that the second gas can smoothly enter the blade 3.

[0135] Among them, the intake wheel cover 21 and the air replenishment wheel cover 22 are connected by an arc when the air replenishment channel 23 is opened.

[0136] The wheel cover 2, which has an air supply channel 23, and the blade 3 are both integrally formed structures. The intake wheel cover 21 and the air supply wheel cover 22 of the wheel cover 2 are connected by an arc-shaped transition portion so as to match and fit with the blade 3. The transition portion includes, but is not limited to, being tangent to both the intake wheel cover 21 and the air supply wheel cover 22, and / or the transition portion includes two tangent arc segments.

[0137] In this embodiment, the impeller cover 2 is welded to the tip of the blade 3, and then an air supply channel 23 is opened on the impeller cover 2. This facilitates the processing of the impeller cover 2 and the air supply channel 23, and helps to improve processing efficiency and reliability. Using the aforementioned blade 3 facilitates the welding of the impeller cover 2 and the blade 3, providing a feasible processing solution for the impeller.

[0138] In some embodiments, the operation of opening the air supply channel 23 on the wheel cover 2 specifically includes:

[0139] During the process of opening the air supply channel 23 on the wheel cover 2, the weld material accumulated during the welding of the wheel cover 2 and the blade tip is removed.

[0140] In this embodiment, by removing the solder accumulated during the welding of the wheel cover 2 and the blade tip during the process of opening the air supply channel 23, it is possible to ensure that the gas has a sufficient flow area, reduce the impact of solder accumulation on airflow, and solve the problem of solder accumulation during the process of forming the air supply channel 23.

[0141] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0142] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A centrifugal impeller, characterized in that, include: The hub (1) is rotatably disposed about its axis; Wheel cover (2), sleeved on the outside of the wheel hub (1), the wheel cover (2) includes an intake wheel cover (21) and an air replenishment wheel cover (22) arranged radially apart, the intake wheel cover (21) has an intake port (211) for intake of a first gas, and an air replenishment channel (23) for intake of a second gas is formed between the intake wheel cover (21) and the air replenishment wheel cover (22). Multiple blades (3), each blade (3) includes an intake section (31), a transition section (32) and an air replenishment section (33) arranged sequentially. The transition section (32) is tangentially connected to the intake section (31) and the air replenishment section (33) by an arc. The transition section (32) includes a first arc portion (321) tangential to the trailing edge of the intake section (31) and a second arc portion (322) tangential to the leading edge of the air replenishment section (33). The first arc portion (321) and the second arc portion (322) are tangentially connected. The intake section (31) is disposed along the axial direction of the hub (1) between the hub (1) and the intake wheel cover (21), and is configured to allow the first gas to flow from the leading edge of the intake section (31) to the trailing edge of the intake section (31) as the hub (1) rotates, so as to perform primary compression on the first gas. The leading edge of the supplementary gas section (33) and the trailing edge of the intake section (31) are connected by the transition section (32) so that the second gas drawn in from the supplementary gas channel (23) is mixed with the first gas after primary compression through the transition section (32) to form a mixed gas. The gas replenishment section (33) is disposed along the axial direction of the hub (1) between the hub (1) and the gas replenishment cover (22), and is configured to allow the mixed gas to flow from the leading edge of the gas replenishment section (33) to the trailing edge of the gas replenishment section (33) as the hub (1) rotates, so as to perform secondary compression on the mixed gas.

2. The centrifugal impeller as described in claim 1, characterized in that, On the vertical projection through the center of the hub (1), the center of the first arc portion (321) is located at the first point (A), the center of the second arc portion (322) is located at the second point (B), and the distance between the first point (A) and the second point (B) along the radial direction of the hub (1) is the first distance (X1). The radii of the first arc portion (321) and the second arc portion (322) are related to the first distance (X1).

3. The centrifugal impeller as described in claim 2, characterized in that, The width of the air supply channel (23) along the radial direction of the hub (1) is the second distance (X2). The first distance (X1) is related to the second distance (X2).

4. The centrifugal impeller as described in claim 3, characterized in that, The first distance (X1) is 2 to 2.5 times the second distance (X2).

5. The centrifugal impeller as described in any one of claims 1 to 4, characterized in that, The radius of the first arc portion (321) is equal to the radius of the second arc portion (322).

6. The centrifugal impeller as described in claim 5, characterized in that, The first arc portion (321) and the second arc portion (322) are tangent to the fifth point (E). The distance between the fifth point (E) and the profiles of the air replenishment section (33) and the air intake section (31) is the third distance. The distance between the profile of the air replenishment section (33) and the profile of the air intake section (31) is the fourth distance (X4). The radii of the first arc portion (321) and the second arc portion (322) are related to the ratio of the third distance and the fourth distance (X4).

7. The centrifugal impeller as described in claim 6, characterized in that, The ratio of the third distance to the fourth distance (X4) is 10%-12%.

8. The centrifugal impeller as described in claim 1 or 3, characterized in that, The flow area of ​​the gas replenishment channel (23) is related to the flow ratio of the second gas and the first gas.

9. The centrifugal impeller as described in claim 8, characterized in that, On the vertical projection through the center of the hub (1), the width of the air supply channel (23) along the radial direction of the hub (1) is the second distance (X2), and the distance between the profile of the air supply section (33) and the profile of the air intake section (31) is the fourth distance (X4). The second distance (X2) and / or the fourth distance (X4) are related to the flow rate ratio of the second gas and the first gas.

10. The centrifugal impeller as described in claim 8, characterized in that, The flow rate ratio of the second gas to the first gas is 8-13%.

11. The centrifugal impeller as claimed in claim 1, characterized in that, On the vertical projection through the center of the hub (1), the center of the second arc portion (322) is located at the second point (B), which is located on the extension line of the inner wall of the air supply channel (23) on the side near the air supply wheel cover (22).

12. A compressor, characterized in that, Includes the centrifugal impeller as described in any one of claims 1 to 11.

13. An air conditioner, characterized in that, Includes the compressor as described in claim 12.

14. A method for manufacturing a centrifugal impeller based on any one of claims 1 to 11, characterized in that, include: The wheel cover (2) is welded to the tip of the blade (3); The air supply channel (23) is opened on the wheel cover (2); Before the air supply channel (23) is opened, the air intake wheel cover (21) and the air supply wheel cover (22) are connected by an arc.

15. The method for manufacturing a centrifugal impeller as described in claim 14, characterized in that, The operation of opening an air supply channel (23) on the wheel cover (2) specifically includes: During the process of opening the air supply channel (23) on the wheel cover (2), the solder accumulated during the welding of the wheel cover (2) and the blade tip is removed.

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