Efficient anti-qi stagnation type multiphase multiphase pump impeller

Abstract

The invention discloses an efficient anti-qi stagnation type multiphase multiphase pump impeller which comprises a hub and a rim, an annular partition plate is arranged between the hub and the rim, a flow channel of a pump is divided into an inner section and an outer section by the partition plate, a through jet hole is formed in the partition plate at the tail section of an outer blade, and the jet hole is located between the two outer blades. An anti-qi stagnation blade is arranged on the hub at the tail sections of the inner blades, the anti-qi stagnation blade is located between the two inner blades, the molded line of the anti-qi stagnation blade is consistent with the molded line of the back surfaces of the inner blades, and the inner side and the outer side of the partition plate are each of a negative curvature structure; a traditional single flow channel is divided into an inner-section double-flow-channel structure and an outer-section double-flow-channel structure in the radial direction, the situation that the pressure gradient is too large due to the fact that a multiphase pump impeller flow channel is too large is avoided, and therefore the gas-liquid separation degree in the flow channel is reduced to a certain degree. In addition, the inner side and the outer side of the partition plate are both of negative curvature structures, curvature centrifugal force opposite to the rotating centrifugal force in direction is generated so as to balance part of the centrifugal force, the gas-liquid separation degree is further reduced, and the gas phase aggregation phenomenon is reduced.

Description

Technical Field

[0001] The invention relates to a spiral axial flow multiphase mixed flow pump, in particular to a high-efficiency anti-gas stagnation type multiphase mixed flow pump impeller. Background Art

[0002] In the fields of deep-sea oil and gas exploitation, oil and gas pipeline transportation, and oil and gas gathering and transportation pipelines, multiphase mixed pumps are one of the core equipment. The spiral axial flow multiphase mixed pump has become an ideal choice for the current and future period due to its simple and compact structure and its suitability for conveying large-flow gas-liquid mixed media. However, in actual operation, especially under medium and high gas content conditions, the conveying efficiency of the mixed pump has dropped significantly. The main reason is the gas-liquid separation and gas phase retention caused by the flow characteristics inside the impeller. Studies have shown that the radial pressure gradient in the rotating impeller is the main cause of gas-liquid separation. Due to the density difference between the gas and liquid phases, the gas gathers toward the center of the impeller under the action of centrifugal force, while the liquid is thrown to the outer edge, forming a gas-liquid separation phenomenon. In addition, the gas phase retention caused by the adverse pressure gradient further aggravates the instability of the flow and reduces the pump's conveying efficiency. These problems not only lead to energy loss, but also cause vibration, noise and cavitation, which seriously affect the reliability and service life of the pump. Summary of the invention

[0003] The object of the present invention is to provide a highly efficient anti-gas stagnation type multiphase mixed flow pump impeller to solve the technical problem of intermittent flow channel blockage caused by gas accumulation at the trailing edge of the blade in the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a high-efficiency anti-gas stagnation type multiphase mixed pump impeller, including a hub and a rim, and blades located between the hub and the rim, an annular partition is provided between the hub and the rim, the partition divides the flow channel of the pump into an inner section and an outer section, the blades located in the inner section are inner blades, and the blades located in the outer section are outer blades, a penetrating jet hole is provided on the partition at the end of the outer blade, the jet hole is located between the two outer blades, an anti-gas stagnation blade is provided on the hub at the end of the inner blade, the anti-gas stagnation blade is located between the two inner blades, the profile of the anti-gas stagnation blade is consistent with the back profile of the inner blade, and the inner and outer sides of the partition are both negative curvature structures.

[0005] Further improvement: when L1 is the blade profile length, in the flow direction, the distance from the jet hole to the front end of the outer blade is L2=(0.7~0.9)L1, in the vertical flow direction, the distance between the jet hole and the outer blade is L3=1~2mm, and the aperture of the jet hole is 1~3mm.

[0006] Further improvement: the length of the anti-stagnation blade L4=(0.1~0.3)L1, in the vertical flow direction, the distance between the front end of the anti-stagnation blade and the inner blade L5=1~2mm, in the flow direction, the distance from the front end of the anti-stagnation blade to the front end of the inner blade L6=(0.7~0.9)L1, the deflection angle α between the anti-stagnation blade and the end of the inner blade=4~6°.

[0007] Further improvement: the outer side of the hub and the inner side of the rim are both negative curvatures, wherein the curvature radius of the hub, partition and rim is R2=(2~2.4)R1, where R1 is the rim radius.

[0008] The advantages of the present invention are as follows: the traditional single flow channel is divided into two sections of inner and outer double flow channel structures along the radial direction, which avoids excessive pressure gradient caused by excessive flow channel of the impeller of the mixed pump, thereby reducing the degree of gas-liquid separation in the flow channel to a certain extent. In addition, the inner and outer sides of the partition adopt a negative curvature structure to generate a curvature centrifugal force in the opposite direction of the rotating centrifugal force to balance part of the centrifugal force, further reduce the degree of gas-liquid separation, and reduce the gas phase aggregation phenomenon.

[0009] In the inner section flow channel structure, an anti-gas stagnation blade is arranged at the end of the inner blade, which can transform the adverse pressure gradient at the tail end of the inner blade into a favorable pressure gradient. The favorable pressure gradient force can push out the gas gathered at the trailing edge of the inner blade, thus avoiding gas blockage in the inner section flow channel.

[0010] In the outer section flow channel structure, by setting a jet hole at the end of the outer blade, part of the inner section jet fluid is guided to flow to the gas phase aggregation area of ​​the outer section, and the jet is used to impact the stagnant gas in the outer section, thereby effectively avoiding gas blockage in the outer section flow channel.

[0011] In summary, the present invention avoids intermittent blockage of the flow channel caused by gas accumulation at the trailing edge of the blade by adopting different control strategies for the inner and outer flow channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of the present invention.

[0013] Figure 2 It is a structural schematic diagram of the outer section of the present invention.

[0014] Figure 3 It is a structural schematic diagram of the inner section of the present invention.

[0015] Figure 4 It is a schematic diagram of the position of the jet hole of the present invention.

[0016] Figure 5 It is a schematic diagram of the position of the anti-gas stagnation blades of the present invention.

[0017] Figure 6It is an axial cross-sectional view of the hub, the partition plate and the rim of the present invention.

[0018] In the figure: hub 1, rim 2, partition 3, outer section 4, outer blade 5, jet hole 6, inner section 7, inner blade 8, anti-stagnation blade 9. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to the accompanying drawings.

[0020] like Figures 1 to 6 As shown, a high-efficiency anti-gas stagnation type multiphase mixed pump impeller includes a hub 1 and a rim 2, and blades located between the hub 1 and the rim 2. An annular partition 3 is provided between the hub 1 and the rim 2, and the partition 3 divides the flow channel of the pump into an inner section 7 and an outer section 4. The blades located in the inner section 7 are inner blades 8, and the blades located in the outer section 4 are outer blades 5. A penetrating jet hole 6 is provided on the partition 3 at the end of the outer blade 5, and the jet hole 6 is located between the two outer blades 5. An anti-gas stagnation blade 9 is provided on the hub 1 at the end of the inner blade 8, and the anti-gas stagnation blade 9 is located between the two inner blades 8. The profile of the anti-gas stagnation blade 9 is consistent with the back profile of the inner blade 8, and the inner and outer sides of the partition 3 are both negative curvature structures.

[0021] When L1 is the blade profile length, in the flow direction, the distance from the jet hole 6 to the front end of the outer blade 5 is L2=(0.7~0.9)L1, in the vertical flow direction, the distance between the jet hole 6 and the outer blade 5 is L3=1~2mm, and the aperture of the jet hole 6 is 1~3mm.

[0022] The length L4 of the anti-stagnation blade 9 is (0.1~0.3)L1. In the direction perpendicular to the flow, the distance L5 between the front end of the anti-stagnation blade 9 and the inner blade 8 is 1~2mm. In the flow direction, the distance L6 from the front end of the anti-stagnation blade 9 to the front end of the inner blade 8 is (0.7~0.9)L1. The deflection angle α between the anti-stagnation blade 9 and the end of the inner blade 8 is 4~6°.

[0023] The outer side of the hub 1 and the inner side of the rim 2 are both negative curvatures, wherein the curvature radius of the hub 1, the partition 3, and the rim 2 is R2=(2~2.4)R1, where R1 is the rim radius.

[0024] Its working principle is as follows: the present invention systematically solves the gas-liquid separation and gas blockage problems in the impeller flow channel of the mixed pump through the innovative dual-channel structure, negative curvature partition 3, anti-gas stagnation blade 9 and jet hole 6 design. After the gas-liquid mixed fluid enters the impeller flow channel, it is radially divided into two sections of inner and outer dual channels for separate treatment. This partition design reduces the size of the single-section flow channel, reduces the pressure gradient, and avoids gas-liquid separation and gas phase aggregation caused by excessive flow channels. The inner and outer sides of the partition 3 adopt a negative curvature structure to generate a curvature centrifugal force opposite to the direction of the rotating centrifugal force, balance part of the centrifugal force, and further reduce the degree of gas-liquid separation. The inner section 7 flow channel converts the adverse pressure gradient at the tail end of the inner blade 8 into a forward pressure gradient through the anti-gas stagnation blade 9. The forward pressure gradient force pushes out the gathered gas, avoiding the gas blockage phenomenon of the inner section 7 flow channel; the outer section 4 flow channel guides part of the inner section 7 jet fluid to flow to the gas phase aggregation area through the jet hole 6, and uses the jet impact to break the gas stagnation gas, avoiding the gas blockage phenomenon of the outer section 4 flow channel. Finally, the treated gas-liquid mixed fluid is output from the flow channel, avoiding gas-liquid separation and gas blockage, and improving the operating efficiency and stability of the mixed flow pump.

[0025] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An efficient anti-gas stagnation type multiphase mixed pump impeller, comprising a hub and a rim, and blades located between the hub and the rim, characterized in that: An annular partition is provided between the hub and the rim, and the partition divides the flow path of the pump into an inner section and an outer section. The blades located in the inner section are inner blades, and the blades located in the outer section are outer blades. A penetrating jet hole is provided on the partition at the end of the outer blade, and the jet hole is located between the two outer blades. An anti-stagnation blade is provided on the hub at the end of the inner blade, and the anti-stagnation blade is located between the two inner blades. The profile of the anti-stagnation blade is consistent with the back profile of the inner blade, and the inner and outer sides of the partition are both negative curvature structures.

2. The high-efficiency anti-gas stagnation type multiphase mixed pump impeller according to claim 1 is characterized in that: When L1 is the blade profile length, in the flow direction, the distance from the jet hole to the front end of the outer blade is L2=(0.7~0.9)L1, in the vertical flow direction, the distance between the jet hole and the outer blade is L3=1~2mm, and the aperture of the jet hole is 1~3mm.

3. The high-efficiency anti-gas stagnation multiphase mixed pump impeller according to claim 2 is characterized in that: The length of the anti-stagnation blade is L4=(0.1~0.3)L1. In the direction perpendicular to the flow, the distance between the front end of the anti-stagnation blade and the inner blade is L5=1~3mm. In the flow direction, the distance from the front end of the anti-stagnation blade to the front end of the inner blade is L6=(0.7~0.9)L1. The deflection angle α between the anti-stagnation blade and the end of the inner blade is 4~6°.

4. A high-efficiency anti-gas stagnation type multiphase mixed pump impeller according to any one of claims 1 to 3, characterized in that: The outer side of the hub and the inner side of the rim are both negative curvatures, wherein the curvature radius of the hub, the partition and the rim is R2=(2~2.4)R1, where R1 is the rim radius.

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