Centrifugal impeller structure with high delivery and delivery device

Abstract

This invention discloses a centrifugal impeller structure and conveying device with high conveying capacity, including a front cover plate and a rear cover plate. The front cover plate and the rear cover plate are provided with flow equalization blades, working blades, and conveying blades. The number of conveying blades is the minimum prime factor of the total number of blades. The conveying blades are formed by a smooth connection of an intake section and a centrifugal section. The profile of the working blades is the same as that of the centrifugal section of the conveying blades. The working blades are centrifugal blades. The profile of the flow equalization blades is the same as that of the working blades, and the length of the flow equalization blades is shorter than that of the working blades. The flow equalization blades, working blades, and conveying blades are arranged in any order along the impeller rotation direction. By introducing an intake section into the centrifugal impeller, positive pre-swirl is provided to reduce the adverse pressure gradient along the flow direction, thereby weakening the resistance effect on solid particles in the flow due to the adverse pressure gradient of the fluid. The arrangement of shorter flow equalization blades increases the inlet flow area of ​​the flow channel where solid particles are more easily accumulated, thereby improving the throughput capacity of solid particles in the centrifugal impeller.

Description

Technical Field

[0001] This invention belongs to the field of fluid transport machinery, specifically relating to a centrifugal impeller structure and transport device with high transport capacity. Background Technology

[0002] The transport of solid-liquid two-phase media is a crucial issue in industries such as wastewater treatment, papermaking, coal mining, and chemicals. Pumps, as a common device for transporting solid-liquid two-phase media, often experience clogging due to the presence of solid particles in the medium, leading to performance degradation, motor overload, and even motor burnout. Designing an impeller structure and transport device with high transport capacity is of great significance for improving the reliability of pump systems and extending their service life.

[0003] Impeller structures used for conveying solid-liquid two-phase media include closed-type centrifugal impellers, open (semi-open) centrifugal impellers, vortex impellers, flow channel impellers, and spiral centrifugal impellers. While closed-type centrifugal impellers offer advantages such as high operating efficiency, good operational stability, and a wide operating range, their capacity for conveying solid-liquid two-phase media is relatively poor, making them prone to clogging when directly used as conveying devices. Furthermore, gap wear limits the application range of open (semi-open) impellers; they are unsuitable for applications with large particles or high particle concentrations, and gap flow losses also lead to a decrease in hydraulic performance. When the conveying capacity of centrifugal impellers (closed, open, and semi-open) for solid-liquid two-phase media cannot meet engineering requirements, traditional methods include reducing the number of blades and increasing the width of the inlet and outlet edges. While traditional methods can improve the conveyability of solid-liquid two-phase media, they also result in a decrease in hydraulic performance. How to improve the conveyability of solid-liquid two-phase media while ensuring hydraulic performance remains a significant unsolved problem in the industry. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a centrifugal impeller structure and conveying device with high conveying capacity, which improves the conveying capacity of solid-liquid two-phase media while ensuring hydraulic performance.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is a centrifugal impeller structure with high conveying capacity, including a front cover plate, a rear cover plate, flow equalization blades, power blades, and conveying blades. The flow equalization blades, power blades, and conveying blades are disposed between the front cover plate and the rear cover plate. The number of conveying blades is the minimum prime factor of the total number of blades. The conveying blades are formed by a smooth connection of an inlet section and a centrifugal section. The profile of the power blades is the same as the profile of the centrifugal section of the conveying blades. The power blades are centrifugal blades. The flow equalization blades have the same profile as the power blades, and the length of the flow equalization blades is less than the length of the power blades. The flow equalization blades, power blades, and conveying blades are arranged in any order along the impeller rotation direction.

[0006] The flow equalization blades, power blades, and conveying blades are all connected to the front cover plate and the rear cover plate to form a closed impeller.

[0007] The flow equalization blades, power blades, and conveying blades are all connected to the rear cover plate to form a semi-open structure.

[0008] The axial structure of the rear cover plate is retained, and the flow equalization blades, power blades and conveying blades are connected to the rear cover plate to form an open impeller structure.

[0009] The inlet section of the conveyor blades can be spiral, axial, inducer-like, or a combination of the three.

[0010] The number of flow equalizing blades is equal to the number of conveying blades, or the number of flow equalizing blades is any integer multiple of the number of conveying blades.

[0011] The number of working blades is equal to the number of conveying blades, or the number of working blades is any integer multiple of the number of conveying blades.

[0012] The flow equalization blades, power blades, and conveying blades are arranged in sequence along the impeller rotation direction.

[0013] The length of the flow equalization blade is 0.6 to 0.8 times the length of the power blade.

[0014] Another conveying device is provided, which adopts the centrifugal impeller structure with high conveying capacity described in this invention.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] 1. By introducing an intake section into the centrifugal impeller, positive pre-swirl is provided to reduce the adverse pressure gradient along the flow direction, thereby weakening the resistance effect on solid particles in the flow due to the adverse pressure gradient of the fluid.

[0017] 2. By arranging shorter flow equalization blades, the inlet flow area of ​​the flow channel where solid particles are more easily accumulated is increased, thereby improving the passage capacity of solid particles in the centrifugal impeller.

[0018] 3. By performing pre-work in the suction section of the conveying blades to compensate for the head drop caused by insufficient work done by the positive pre-swirl and flow equalization blades, the impeller's ability to convey solid-liquid two-phase media is effectively improved while ensuring the impeller's work capacity.

[0019] 4. By using flow equalization blades, the problem of uneven flow distribution in the flow channel caused by the suction section of the conveying blades is improved, so that the maximum flow difference between each flow channel is less than 5% of the total flow, avoiding the accumulation of solid particles in some flow channels due to insufficient flow, and ensuring the centrifugal impeller's ability to convey solid and liquid two-phase media. Attached Figure Description

[0020] Figure 1This is a schematic diagram of an embodiment of the present invention;

[0021] Figure 2 This is a meridional plane view according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the blade arrangement after removing the front cover plate in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the conveying blades in an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the working blades in an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the flow equalization blades in an embodiment of the present invention;

[0026] Figure 7 This is an axial projection view of the flow channel according to an embodiment of the present invention;

[0027] Figure 8 The velocity contour map is obtained from numerical simulation in an embodiment of the present invention.

[0028] The following are the labels in the diagram: 1. Front cover plate; 2. Rear cover plate; 3. Flow equalization blade; 4. Power blade; 5. Conveying blade; 6. Suction section; 7. Centrifugal section; 8. Flow channel between the suction surface of the conveying blade and the pressure surface of the power blade; 9. Flow channel between the suction surface of the power blade and the pressure surface of the flow equalization blade; 10. Flow channel between the suction surface of the flow equalization blade and the pressure surface of the conveying blade. Detailed Implementation

[0029] To facilitate understanding by those skilled in the art, the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] like Figure 1 , Figure 2 , Figure 3 As shown, a centrifugal impeller structure and conveying device with high conveying capacity includes a front cover plate 1, a rear cover plate 2, flow equalization blades 3, working blades 4, and conveying blades 5; the flow equalization blades 3, working blades 4, and conveying blades 5 are arranged between the front cover plate 1 and the rear cover plate 2; the number of blades of the conveying blades 5 is the minimum prime factor of the total number of blades; the conveying blades 5 are formed by a smooth connection of an inlet section 6 and a centrifugal section 7; the profile of the working blades 4 is the same as the profile of the centrifugal section of the conveying blades, and the working blades 4 are centrifugal blades; the flow equalization blades 3 and working blades 4 have the same profile, and the length of the flow equalization blades 3 is less than the length of the working blades 4; the flow equalization blades 3, working blades 4, and conveying blades 5 can be arranged in any order along the impeller rotation direction, and the length of the flow equalization blades 3 is determined by the flow difference between the flow channels on both sides of the flow equalization blades 3.

[0031] like Figure 4The conveying blade 5 includes an intake section 6 and a centrifugal section 7, which are connected to each other and smoothly transition.

[0032] like Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6 As shown, the centrifugal impeller structure and conveying device of the present invention have high conveying capacity. The centrifugal impeller can be a closed impeller structure, specifically, the flow equalization blade 3, the power blade 4, and the conveying blade 5 are all connected to the front cover plate and the rear cover plate to form a closed impeller; it can be a semi-open impeller structure, specifically, the flow equalization blade 3, the power blade 4, and the conveying blade 5 are all connected to the rear cover plate to form a semi-open structure; it can also be an open impeller structure, specifically, the axial structure of the rear cover plate 1 is retained, and the flow equalization blade 3, the power blade 4, and the conveying blade 5 are connected to the rear cover plate 1 to form an open impeller structure; the specific structural form is determined according to the hardness of the solid particles, the concentration of the solid particles, and other conditions.

[0033] The suction section 6 of the conveying blade 5 can be helical, axial, or inducer-like, or a combination of these three types. The specific form of the suction section 6 needs to be determined based on factors such as the inlet fluid flow direction of the suction section 6, the inlet blade angle of the centrifugal section 7, the pre-work head of the suction section 6, and the concentration of solid particles in the solid-liquid two-phase medium. The outlet blade angle of the suction section 6 is determined by the inlet blade angle of the centrifugal section 7, and the inlet installation angle of the suction section 6 is determined by the head compensation required for the suction section 6. The number of flow equalization blades 3 can be equal to or an integer multiple of the number of blades in the conveying blade 5. Under the premise of ensuring circumferential structural symmetry, the greater the periodic influence of the suction section 6 of the conveying blade on the circumferential velocity, the more blades the flow equalization blades 3 should have.

[0034] The length of the flow equalization blade 3 is 0.6 to 0.8 times the length of the power blade 4; the arrangement sequence can also be that the flow equalization blade 3, the power blade 4, and the conveying blade 5 are arranged sequentially along the impeller rotation direction, and the position of the flow equalization blade 3 is determined by the high flow area at the outlet of the conveying blade suction section 6.

[0035] When the solid-liquid two-phase medium just enters the blade, the suction section 6 of the conveying blade 5 does work on the medium, increasing the fluid energy and the circumferential velocity of the fluid. The increase in circumferential velocity will lead to an increase in positive pre-swirl at the inlet of the centrifugal section 7 of the conveying blade, the inlet of the power blade 4, and the inlet of the flow equalization blade 3, which will reduce the adverse pressure gradient along the flow direction, thereby weakening the resistance effect on solid particles in the flow due to the adverse pressure gradient of the fluid. The increase in fluid energy will compensate for the decrease in head caused by the increase in positive pre-swirl at the inlet of the centrifugal section 7 of the conveying blade 5, the inlet of the power blade 4, and the inlet of the flow equalization blade 3, as well as the insufficient work capacity of the flow equalization blade, so that the overall hydraulic performance of the impeller does not change significantly.

[0036] like Figure 7 The present invention features a centrifugal impeller structure and conveying device with high conveying capacity, including flow channels 8 between the suction surface of the conveying blades and the pressure surface of the working blades, flow channels 9 between the suction surface of the working blades and the pressure surface of the flow equalization blades, and flow channels 10 between the suction surface of the flow equalization blades and the pressure surface of the conveying blades; when fluid flows into the centrifugal section of the impeller, such as Figure 7 As shown, the shorter flow equalization blade 3 allows the inlet of the flow channel 9 between the suction surface of the power blade and the pressure surface of the flow equalization blade, and the inlet of the flow channel 10 between the suction surface of the flow equalization blade and the pressure surface of the conveying blade to have a larger flow area, thereby increasing the throughput of solid particles at the inlet of the centrifugal impeller.

[0037] Due to the effect of slippage, the work done on the medium by the suction section 6 of the conveying blade 5 will periodically disrupt the circumferential velocity at the outlet of the suction section 6 of the conveying blade 5, resulting in significant differences in flow rates across different channels. In channels with lower flow rates, the solid-liquid two-phase medium has lower velocity, and the solid particles move at lower speeds, making them prone to accumulation and blockage. For example... Figure 8 As shown, the arrangement of the flow equalization blades 3 will change the inlet position of the flow channel, delaying or advancing the flow distribution in part of the flow channel, thus satisfying the principle that the maximum flow difference in the flow channel is less than 5% of the total flow. This will help avoid the accumulation of solid particles in the flow channel due to insufficient flow, thereby improving the conveying performance.

[0038] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A centrifugal impeller structure having high delivery, characterized by, It includes a front cover plate (1), a rear cover plate (2), flow equalization blades (3), power blades (4), and conveying blades (5). The flow equalization blades (3), power blades (4), and conveying blades (5) are arranged between the front cover plate (1) and the rear cover plate (2). The number of blades of the conveying blades (5) is the smallest prime factor of the total number of blades. The conveying blades (5) are formed by a smooth connection of the suction section (6) and the centrifugal section (7). The profile of the power blades (4) is the same as the profile of the centrifugal section of the conveying blades. The power blades (4) are centrifugal blades. The profile of the flow equalization blades (3) is the same as that of the power blades (4). The length of the flow equalization blades (3) is less than the length of the power blades (4). The flow equalization blades (3), power blades (4), and conveying blades (5) are arranged in any order along the impeller rotation direction.

2. The centrifugal impeller structure having high delivery according to claim 1, wherein The flow equalization blade (3), the power blade (4), and the conveying blade (5) are all connected to the front cover plate and the rear cover plate to form a closed impeller.

3. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The flow equalization blade (3), the power blade (4), and the conveying blade (5) are all connected to the rear cover plate to form a semi-open structure.

4. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The axial structure of the rear cover plate (1) is retained, and the flow equalization blade (3), the power blade (4) and the conveying blade (5) are connected to the rear cover plate (1) to form an open impeller structure.

5. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The inlet section of the conveyor blade (5) can be spiral, axial, inducer-like, or a combination of the three.

6. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The number of blades in the flow equalization blade (3) is equal to the number of blades in the conveying blade (5), or the number of blades in the flow equalization blade (3) is any integer multiple of the number of blades in the conveying blade (5).

7. The centrifugal impeller structure with high conveying capacity according to claim 6, characterized in that, The number of working blades (4) is equal to the number of conveying blades (5), or is any integer multiple of the number of working blades (4) and the number of conveying blades (5).

8. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The flow equalization blades (3), the power blades (4), and the conveying blades (5) are arranged in sequence along the impeller rotation direction.

9. The centrifugal impeller structure with high conveying capacity according to claim 1, characterized in that, The length of the flow equalization blade (3) is 0.6 to 0.8 times the length of the power blade (4).

10. A conveying device, characterized in that, The centrifugal impeller structure with high conveying capacity described in any one of claims 1-9 is adopted.

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