CN110701110A - Volute type centrifugal pump with movable guide vanes - Google Patents
Volute type centrifugal pump with movable guide vanes Download PDFInfo
- Publication number
- CN110701110A CN110701110A CN201911041271.0A CN201911041271A CN110701110A CN 110701110 A CN110701110 A CN 110701110A CN 201911041271 A CN201911041271 A CN 201911041271A CN 110701110 A CN110701110 A CN 110701110A
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- CN
- China
- Prior art keywords
- centrifugal pump
- volute
- impeller
- flow
- guide vane
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/44—Fluid-guiding means, e.g. diffusers
- F04D29/46—Fluid-guiding means, e.g. diffusers adjustable
- F04D29/466—Fluid-guiding means, e.g. diffusers adjustable especially adapted for liquid fluid pumps
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/426—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for liquid pumps
- F04D29/4293—Details of fluid inlet or outlet
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/669—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for liquid pumps
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a volute type centrifugal pump with movable guide vanes. The volute type centrifugal pump with the movable guide vanes is provided with the flow straightener at the outlet of the suction elbow, so that the energy loss of fluid at the inlet of a flow channel is reduced, the cavitation performance is improved, and the vibration and the noise are reduced. The movable guide vane structure of the volute type centrifugal pump with the movable guide vanes is arranged between an impeller outlet and a volute inlet, the angle of the guide vanes can be adjusted according to different working conditions, liquid flow at the impeller outlet can be rectified under different working conditions, the influence of unbalanced force is reduced, and the operation stability of a large-scale unit is improved. And the structure is favorable for reducing the impact loss caused by the impact of water flow on the guide vane when the liquid flow at the outlet of the impeller enters the guide vane, thereby improving the efficiency of the large centrifugal pump.
Description
Technical Field
The invention relates to a volute type centrifugal pump with movable guide vanes, and belongs to the technical field of water pumps.
Background
The large centrifugal pump unit is mainly applied to the field of large hydraulic engineering such as water resource allocation, agricultural water consumption and the like, and is characterized by large structural size and large hydraulic unbalance force. Due to the economic cost constraint caused by the foundation excavation amount and the limitation of the site space condition, the elbow type water suction chamber is adopted in the large-scale pump station. The liquid flow is easy to generate large-scale vortex at the position of the suction elbow bend, so that the flow of the liquid flow is very uneven, and large resistance loss and friction loss are generated in the operation process of the centrifugal pump, and large noise and vibration are generated. In a larger structural size, the volute is of a thin-wall structure, the stability of the structure is weak, and unbalanced excitation can be generated by unbalanced force in the operation process; in a large centrifugal pump unit, the generated hydraulic unbalanced force is very large, and can generate larger vibration and overlarge local stress, thereby generating adverse effect on a rotor system running at high speed.
Disclosure of Invention
The invention aims to provide a volute type centrifugal pump with movable guide vanes, which can always keep the running efficiency of the pump in the optimal condition under different working conditions.
In order to realize the purpose, the invention adopts the technical scheme that: the utility model provides a volute type centrifugal pump with activity stator, includes the spiral case, inhales elbow pipe and impeller, the impeller with install a plurality of activity stator between the internal face of spiral case, the activity stator is evenly arranged around the impeller, and every the position of activity stator can be followed simultaneously the impeller is adjustable.
In the above scheme, each movable guide vane is fixedly installed on the fixed shaft, the lower end of the fixed shaft is connected with the bottom ring revolute pair, the upper end of the fixed shaft is fixedly provided with the shaft sleeve, one end of the connecting arm is hinged with the shaft sleeve, the other end of the connecting arm is hinged on the control ring, the same side of the control ring is hinged with the piston rod, and each piston rod is installed on the servomotor.
In the above scheme, the bottom ring is in sealing connection with the volute, and the fixed shaft is in sealing connection with the volute.
In the above scheme, a flow straightener is arranged at the outlet of the suction elbow.
In the above scheme, the fairing includes first cowling panel and second cowling panel, the central line collineation of first cowling panel and second cowling panel to the contained angle between first cowling panel and the second cowling panel is 90.
The invention has the beneficial effects that: (1) the invention is beneficial to improving the flowing condition of the incoming flow of the impeller, stabilizing the inlet flow field, realizing the stable operation in the impeller, improving the efficiency of the unit, reducing vibration and noise and prolonging the service life of the blade. (2) The invention solves the problem of overlarge radial unbalanced force of the rotor of the volute type large centrifugal pump, and reduces the unbalanced force applied to a static part and a rotor system by rectifying the liquid flow between the impeller and the volute through the movable guide vane. (3) The guide vane adjusting device realizes guide vane adjustment aiming at the multi-working-condition operation conditions of the unit, and meets the requirements of efficient and stable operation under different working conditions. The guide vane is adjustable, so that the impact loss generated when the liquid flow at the outlet of the impeller enters the guide vane can be effectively reduced, and the multi-working-condition efficient and stable operation is realized. (4) The invention arranges the flow-regulating grid at the outlet of the suction elbow, reduces the energy loss of the fluid at the inlet of the runner, improves the cavitation performance by weakening the influence of secondary flow and vortex, and reduces the vibration and noise. The guide vane is set to be an adjustable structure, so that multi-working-condition efficient operation is realized, unbalanced force generated in operation is reduced, and the efficiency and the operation stability of the large-scale unit are improved.
Drawings
FIG. 1 is a schematic view of the overall structure of a volute centrifugal pump with movable vanes;
FIG. 2 is a schematic view of a movable vane position;
FIG. 3 is a schematic view of the position of the flow straightener in the suction elbow;
FIG. 4 is a schematic view of a rectifier gate structure;
FIG. 5 is a schematic view of a movable vane configuration;
FIG. 6 is a top view of the movable vane;
FIG. 7 is a triangle of the exit velocity of the impeller as conditions change;
FIG. 8 is a schematic view of a vane improved fore-aft structure and speed triangle.
FIG. 9 is a triangular schematic view of the improved structure and speed of the guide vane.
In the figure: 1. a volute; 2. a movable guide vane; 3. an impeller; 4. a suction elbow; 5. a rectifying grid; 5-1, a first rectifying plate; 5-2, a second rectifying plate; 6. a fixed shaft; 7. a bottom ring; 8. a shaft sleeve; 9. a connecting arm; 10. a control loop; 11. a servomotor; 12. a piston rod.
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments, but the scope of the invention should not be limited thereby.
Referring to fig. 1 and 2, the volute type centrifugal pump with movable guide vanes of the present embodiment is composed of 4 components, including a volute 1, a suction elbow 4, an impeller 3, and a plurality of movable guide vanes 2, the movable guide vanes 2 are arranged between the impeller 3 and an inner wall surface of the volute 1, a fluid enters the centrifugal pump from the suction elbow 4 and flows to the impeller 3, and after exiting from the impeller 3, the fluid first passes through the movable guide vanes 2 and then flows out from the volute 1. The flow passage component of the centrifugal pump is designed according to the rated flow, when the pump runs under the design working condition, the flow condition of the liquid in the pump is in accordance with the geometric shape of the flow passage component, at this time, no impact loss is generated, but when the flow of the pump running deviates from the design value, the shape of the flow passage component is not in accordance with the flow condition, thereby generating the impact loss, and the movable guide vane 2 of the embodiment is movable, and the corresponding position adjustment can be carried out according to the working condition, so that the shape of the movable guide vane is in accordance with the flow condition of the liquid when the liquid flows through the guide vane.
Referring to fig. 3, a flow straightener 5 is disposed in the suction elbow 4, and the flow straightener 5 is installed at the outlet of the suction elbow 4 through a fixing hole 6 to straighten the incoming flow and reduce the influence of the secondary flow and the vortex. The shape of the rectifying grid 5 is as shown in fig. 4, and comprises a first rectifying plate 5-1 and a second rectifying plate 5-2, the central lines of the first rectifying plate 5-1 and the second rectifying plate 5-2 are collinear, the included angle between the first rectifying plate 5-1 and the second rectifying plate 5-2 is 90 degrees, and the planar projection of the first rectifying plate 5-1 and the second rectifying plate 5-2 is a cross structure.
Referring to fig. 5 and 6, each movable guide vane 2 is fixedly mounted on a fixed shaft 6, the lower end of the fixed shaft 6 is connected with a bottom ring 7 revolute pair, a shaft sleeve 8 is fixedly mounted at the upper end of the fixed shaft 6, one end of a connecting arm 9 is hinged with the shaft sleeve 8, the other end of the connecting arm is hinged with a control ring 10, piston rods 12 are hinged to the same side of the control ring 10, and each piston rod 12 is mounted on a servomotor 11. The bottom ring 7 is in sealing connection with the volute 1, and the fixed shaft 6 is in sealing connection with the volute 1. When the position of the movable guide vane 2 needs to be adjusted, the servomotor 11 drives the piston rod 12 to stretch and retract, so that the control ring 10 rotates at a certain angle, the connecting arm 9 drives the shaft sleeve 8 to rotate under the rotation of the control ring 10, and the movable guide vane 2 is fixedly connected with the shaft sleeve 8, so that the position adjustment of the whole movable guide vane 2 relative to the impeller 3 within a certain angle range is realized under the driving of the corresponding shaft sleeve 8.
Referring to fig. 7, wherein,V 2is the impeller exit absolute velocity;W 2is the impeller exit relative velocity;U 2is the impeller exit peripheral velocity;V m2is the impeller outlet axial plane velocity;V u2the circumferential component velocity is the absolute velocity of the impeller outlet;αis the absolute fluid flow angle at the impeller outlet;βis the relative flow angle of the impeller outlet; q is the actual flow. When the working condition changes, the absolute speed of the outlet of the impellerV 2And the peripheral speedU 2Angle of (2)αThe relative speed of the liquid flow at the outlet of the blade is correspondingly changedW 2The direction of which depends on the direction of the vanes as a result of their confinement, the relative velocity of the liquid flow at the outlet of the vanesW 2The direction of the pressure-sensitive adhesive is consistent with the tangential direction of the surface of the outlet of the blade and is constant, so that the relative speedW 2And the peripheral speedU 2Angle of (2)βIs constant. In the impeller with limited blades, the liquid flow is greatly weakened by the clamping degree of the blades, so that the inertia of the liquid flow is expressed, and the liquid flow between the blades generates a rotating motion which is opposite to the angular velocity direction of the impeller and is equal to the angular velocity direction of the impeller, namely, an axial vortex. The relative velocity is produced due to the presence of axial vorticesSlip, resulting in insufficient rotation of the liquid stream at the outlet, resulting in poor flow controlβIs smaller than the blade outlet setting angle. When the volute type centrifugal pump is not provided with the radial guide vane mechanism, the strongest interference point is positioned at the position of the partition tongue when the impeller operates, radial unbalanced force can be generated due to the interference, and the unbalanced force can generate adverse influence on the stability of the operation of the pump set. After the radial guide vane is added, the interference generated between the radial guide vane and the impeller blade is the guide vane inlet edge, and meanwhile, the interference position is uniformly distributed around the impeller, so that the radial force caused by the interference can be effectively balanced, and the radial guide vane is favorable for reducing the radial force of the rotor and improving the operation stability.
Referring to fig. 8 and 9, in which,v m0is the guide vane inlet radial velocity;w 0is the guide vane inlet absolute velocity;α 0is composed ofw 0AndU 2the included angle of (A);α’and an angle is arranged for the inlet of the guide vane. Due to the peripheral speedU 2The value of (A) is kept constant, and the radial speed of the blade inlet is changed when the working condition is changedv m0Increases with increasing flow Q, resulting in vane inlet absolute velocityw 0Change the inlet absolute speed of the guide vanew 0And the peripheral speedU 2Angle of (2)α 0A corresponding change occurs. Because the guide vane inlet placing angle of the fixed guide vaneα' is constant, the flow creates significant impact at the inlet of the guide vane, causing impact losses; and the inlet mounting angle of the movable guide vaneαThe flow guide vane can be adjusted according to the size of the flow angle, so that liquid flows smoothly enter the guide vane section, and the impact loss at the inlet of the guide vane is effectively reduced. Fluid flow angle under different working conditionsα 0Can be calculated according to the velocity triangle shown in the figure to make the liquid flow angleα 0Size of and guide vane inlet mounting angleαThe inlet mounting angles of the guide vanes under different working conditions can be obtained through accurate calculationα' so as to determine the opening degree of the guide vane under different working conditions and provide operation reference for efficient and stable operation under different working conditions. The calculation process is as follows:
at the inlet of the guide vane, the absolute speedw 0Can be decomposed into radial velocitiesv m0And peripheral speedU 2The relationship is:w 0 2=v m0 2+U 2 2. Whereinv m0=Q/S 0（S 0Effective area at the inlet of the guide vane); flow angle at the inlet of the guide vaneα’0Is tanα’0=v m0/U 2,α’0=arctan(v m0/U 2) Centrifugal pump guide vane setting angle with movable guide vaneα' adjustment of the reference flow Angleα’0And calculating a result. When in the low-flow condition,v m0will be reduced,U 1It will be increased in the size of the pipe,α’0according toα’0=arctan(v m0/U 2) It will be smaller; on the contrary, under the working condition of large flow,α’0it becomes large. Therefore, in the operation of the unit, the guide vane is required to be placed at an angle under the working condition of low flowαThe guide vane is required to be arranged at an angle under the working conditions of small adjustment and large flowα' Turn up.
Claims (5)
1. The utility model provides a volute type centrifugal pump with activity stator, includes spiral case (1), inhales elbow pipe (4) and impeller (3), its characterized in that, impeller (3) with install a plurality of activity stator (2) between the internal face of spiral case (1), activity stator (2) evenly arrange around impeller (3), and every the position of activity stator (2) can be simultaneously along impeller (3) are adjustable.
2. The volute type centrifugal pump with the movable guide vanes according to claim 1, wherein each movable guide vane (2) is fixedly installed on a fixed shaft (6), the lower end of the fixed shaft (6) is connected with a rotating pair of a bottom ring (7), the upper end of the fixed shaft (6) is fixedly provided with a shaft sleeve (8), one end of a connecting arm (9) is hinged with the shaft sleeve (8), the other end of the connecting arm is hinged with a control ring (10), a piston rod (12) is hinged to the same side of the control ring (10), and each piston rod (12) is installed on a servomotor (11).
3. Volute centrifugal pump with moving vanes according to claim 2, characterized in that there is a sealed connection between the bottom ring (7) and the volute (1), and between the stationary shaft (6) and the volute (1).
4. Volute centrifugal pump with moving vanes according to claim 1 or 2 or 3, characterized in that the outlet of the suction elbow (4) is provided with a flow straightener (5).
5. Volute centrifugal pump with moving guide vanes according to claim 4, characterized in that the flow straightener (5) comprises a first flow straightener (5-1) and a second flow straightener (5-2), the centre lines of the first flow straightener (5-1) and the second flow straightener (5-2) are collinear, and the angle between the first flow straightener (5-1) and the second flow straightener (5-2) is 90 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911041271.0A CN110701110A (en) | 2019-10-30 | 2019-10-30 | Volute type centrifugal pump with movable guide vanes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911041271.0A CN110701110A (en) | 2019-10-30 | 2019-10-30 | Volute type centrifugal pump with movable guide vanes |
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| Publication Number | Publication Date |
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| CN110701110A true CN110701110A (en) | 2020-01-17 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911041271.0A Pending CN110701110A (en) | 2019-10-30 | 2019-10-30 | Volute type centrifugal pump with movable guide vanes |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112160941A (en) * | 2020-09-09 | 2021-01-01 | 江苏大学 | Guide vane combination structure for improving unstable hump phenomenon of volute type centrifugal pump |
| CN113236607A (en) * | 2021-06-11 | 2021-08-10 | 浙江理工大学 | Design method of large-scale engineering pump volute and volute thereof |
| WO2022227244A1 (en) * | 2021-04-28 | 2022-11-03 | 江苏大学 | Flow-adaptive guide vane adjustment device based on hydraulic transmission |
| CN116044815A (en) * | 2023-01-20 | 2023-05-02 | 江苏大学 | Suction chamber for improving cavitation performance of condensate pump |
| WO2024152817A1 (en) * | 2023-01-17 | 2024-07-25 | 东方电气集团东方电机有限公司 | Large-power-variable-amplitude variable-speed pump |
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| CN205371092U (en) * | 2016-01-21 | 2016-07-06 | 池泉 | Adjustable vane device and festival segmentation multistage centrifugal pump |
| CN107503978A (en) * | 2017-09-19 | 2017-12-22 | 河海大学 | A kind of high-lift higher specific speed mixed-flow pump |
| CN107559238A (en) * | 2017-08-07 | 2018-01-09 | 江苏大学 | A kind of import guiding device for improving canned motor pump cavitation performance |
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Patent Citations (7)
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| US20040067133A1 (en) * | 2001-11-01 | 2004-04-08 | Eiichi Ishigaki | Turbo pump |
| CN201554699U (en) * | 2009-11-20 | 2010-08-18 | 无锡杰尔压缩机有限公司 | Diffusion guide vane synchronization adjusting mechanism of high-speed centrifugal fan |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112160941A (en) * | 2020-09-09 | 2021-01-01 | 江苏大学 | Guide vane combination structure for improving unstable hump phenomenon of volute type centrifugal pump |
| WO2022227244A1 (en) * | 2021-04-28 | 2022-11-03 | 江苏大学 | Flow-adaptive guide vane adjustment device based on hydraulic transmission |
| GB2608721A (en) * | 2021-04-28 | 2023-01-11 | Univ Jiangsu | Flow-adaptive guide vane adjustment device based on hydraulic transmission |
| GB2608721B (en) * | 2021-04-28 | 2023-08-02 | Univ Jiangsu | Flow-adaptive guide vane adjustment device based on hydraulic transmission |
| CN113236607A (en) * | 2021-06-11 | 2021-08-10 | 浙江理工大学 | Design method of large-scale engineering pump volute and volute thereof |
| CN113236607B (en) * | 2021-06-11 | 2022-06-28 | 浙江理工大学 | Design method of large-scale engineering pump volute and volute thereof |
| WO2024152817A1 (en) * | 2023-01-17 | 2024-07-25 | 东方电气集团东方电机有限公司 | Large-power-variable-amplitude variable-speed pump |
| CN116044815A (en) * | 2023-01-20 | 2023-05-02 | 江苏大学 | Suction chamber for improving cavitation performance of condensate pump |
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Application publication date: 20200117 |