A splitter blade device and working method for suppressing large-scale stall vortex in a mixed flow pump

Abstract

The present invention discloses a splitter blade device and a working method for suppressing large-scale stall vortices in a mixed flow pump, which relates to the field of internal flow technology of fluid machinery, and includes a shaft connection part, an impeller hub and several main blades; the shaft connection part is installed on the main shaft, the impeller hub is installed on the shaft connection part, and the main blades are circumferentially arranged on the impeller hub; several expansion joints are opened on the impeller hub, and the number of expansion joints is the same as the number of main blades; one end of movable rods A, B and C are arranged in the expansion joints through a rotating shaft, and the rotating shaft can be driven by a power source; the other ends of movable rods A, B and C are arranged on splitter blades; the rotating shaft rotates to drive movable rods A, B and C to rotate, thereby expanding and retracting the splitter blades; an external computer is used to process data and send signals. The present invention arranges splitter blades in the impeller flow channel to disperse the flow to achieve a method of improving the flow field in the impeller of the mixed flow pump.

Description

Technical Field

[0001] The present invention relates to the technical field of internal flow in fluid machinery, and in particular to a splitter blade device and a working method for suppressing large-scale stall vortices in a mixed-flow pump. Background Art

[0002] A mixed-flow pump is a type of pump between centrifugal and axial-flow pumps, characterized by axial inlet flow and oblique outlet flow. It offers higher head and lower flow rates than axial-flow pumps, but higher flow rates than centrifugal pumps. Therefore, it is widely used in sewage treatment, flood control and drainage, and agricultural irrigation. However, as the application of mixed-flow pumps expands, performance requirements are also increasing. However, due to the incompleteness of mixed-flow pump design theory, it is currently impossible to design a mixed-flow pump that achieves maximum efficiency under all flow conditions. In particular, when a mixed-flow pump operates under low-flow conditions, the increased angle of attack at the impeller inlet can easily cause backflow behind the impeller blades. As the backflow zone increases, one impeller channel becomes blocked, diverting water to an adjacent channel. This causes a change in the angle of attack at the inlet of the adjacent channel, creating a vortex structure in the flow passage of the next-stage impeller and a blockage effect. This blockage, which repeats itself along the impeller axis, can cause "rotating stall." During this period, the unsteady flow in the mixed-flow pump increases, and its unsteady characteristics become more pronounced. This can lead to abnormal vibration and noise throughout the unit, seriously threatening operational safety. Therefore, to improve the stability of the mixed-flow pump during stall conditions and reduce the impact of the "stall mass" on the flow field, it is necessary to develop a device or structure that eliminates or mitigates the negative impact of the "stall mass" on the flow field within the mixed-flow pump impeller.

[0003] After searching, the patent application number CN202320524343.2 installs splitter blades between the main blades, but its purpose is only to recover residual pressure energy, and the splitter blades are fixed, which does not improve the "rotational stall" phenomenon. Moreover, the impeller is only suitable for relatively small flow conditions. When the flow rate is large, it is more likely to cause clogging. The patent application number CN201711241684.4 injects high-speed fluid into the boundary layer through an ejector to prevent the propagation of the stall vortex, but this method is only suitable for pumps with thicker blades and is only effective when the flow rate is relatively small. When the flow rate is relatively large, the effect is minimal. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a splitter blade device for suppressing large-scale stall vortices in a mixed flow pump. By arranging splitter blades in the impeller flow channel, the flow is dispersed to improve the flow field in the impeller of the mixed flow pump.

[0005] The present invention achieves the above technical objectives through the following technical means.

[0006] A splitter blade device for suppressing large-scale stall vortices in a mixed-flow pump comprises a shaft connection portion, an impeller hub and several main blades; the shaft connection portion is mounted on the main shaft, the impeller hub is mounted on the shaft connection portion, and the main blades are circumferentially arranged on the impeller hub; several expansion joints are opened on the impeller hub, and the number of expansion joints is the same as the number of main blades; movable rods A, B and one end of movable rod C are arranged in the expansion joints through a rotating shaft, and the rotating shaft can be driven by a power source; the other ends of the movable rods A, B and C are arranged on the splitter blades; the rotation of the rotating shaft drives the movable rods A, B and C to rotate, thereby expanding and retracting the splitter blades; an external computer is used to process data and send signals.

[0007] In the above solution, the splitter blades are made of flexible material.

[0008] In the above solution, a micro pore water pressure sensor is provided on the suction surface of the main blade; the micro pore water pressure sensor is used to monitor the water pressure change in the flow channel and transmit the electrical signal to the computer.

[0009] In the above solution, the height of the splitter blade is half of the height of the main blade.

[0010] In the above solution, the expansion joint is located in the middle of adjacent main blades on the impeller hub.

[0011] In the above solution, the movable rod A, the movable rod B and the movable rod C are capable of extension and contraction.

[0012] In the above solution, the shaft connection part, the main blades and the impeller hub are integrally formed.

[0013] The working method of the splitter blade device for suppressing large-scale stall vortex in a mixed flow pump is as follows: after the splitter blade device is installed in the mixed flow pump, water and power are supplied. At the beginning of operation, the splitter blades are retracted into the expansion joint, and the micro-pore water pressure sensor transmits data to the computer for analysis. When the calculated pressure coefficient |C P When |>0.05, the computer issues a command to expand the splitter blades. After receiving the command, the movable rods A, B, and C rotate counterclockwise and extend, driving the splitter blades to expand and disrupting the flow field in the impeller channel. At the same time, the micro pore water pressure sensor continues to transmit data to the computer for analysis. When the pressure coefficient |C P When |>0.02, the computer issues a command to retract the splitter blades. After receiving the command, the movable rods A, B, and C in the impeller expansion joint rotate and retract clockwise, driving the splitter blades to retract into the expansion joint.

[0014] Beneficial effects:

[0015] 1. The present invention is provided with diverter blades. When the mixed flow pump has a "rotational stall" phenomenon, the movable rod moves to expand the diverter blades to divert the channel and make the channel smooth. When the "rotational stall" phenomenon disappears, the diverter blades are retracted. This process is repeated, which can not only suppress the large-scale stall vortex in the mixed flow pump, but also reduce the vibration problem of the pump, improve the efficiency of the pump, and extend the service life. The design of the diverter blades is that when the mixed flow pump is operating at a low flow rate, the micro flow sensor monitors the flow rate and transmits the data to the computer for analysis. If it is found that a channel of the impeller is blocked, an action command is issued, the movable rod moves, and the diverter blades are expanded to divert the channel, so that the channel is smooth, thereby reducing the vibration problem of the pump.

[0016] 2. In the present invention, the splitter blades are arranged on the impeller hub, which is convenient for installation, can reduce the vibration of the pump, and improve the efficiency of the pump. The height of the splitter blades is half of the height of the main blades, which is convenient for contraction and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the overall system structure of the splitter blade device for suppressing large-scale stall vortices in a mixed flow pump;

[0018] Figure 2 Detailed diagram of the splitter blades of a splitter blade assembly for suppressing large-scale stall vortices in a mixed-flow pump;

[0019] Figure 3 A diagram showing the retracted splitter blades of a splitter blade device for suppressing large-scale stall vortices in a mixed-flow pump;

[0020] Figure 4 A detailed diagram of the retracted splitter blades of a splitter blade device for suppressing large-scale stall vortices in a mixed-flow pump;

[0021] Figure 5 A schematic diagram of the impeller front structure of a splitter blade device used to suppress large-scale stall vortices in a mixed flow pump;

[0022] Figure 6 Schematic diagram of the impeller side structure of the splitter blade device used to suppress large-scale stall vortex in a mixed flow pump.

[0023] Reference numerals:

[0024] 1-shaft connection; 2-impeller hub; 3-main blade; 4-movable rod A; 5-movable rod B; 6-movable rod C; 7-expansion joint; 8-micro pore water pressure sensor; 9-micro pore water pressure sensor signal line; 10-diverter blade; 11-movable rod signal line; 12-bus; 13-main shaft; 14-slip ring; 15-computer. DETAILED DESCRIPTION

[0025] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0028] A splitter blade device for suppressing large-scale stall vortices in a mixed flow pump comprises a shaft connection portion 1, an impeller hub 2 and several main blades 3; the shaft connection portion 1 is mounted on a main shaft 13, the impeller hub 2 is mounted on the shaft connection portion 1, and the main blades 3 are circumferentially arranged on the impeller hub 2; several expansion joints 7 are provided on the impeller hub 2, and the number of the expansion joints 7 is the same as the number of the main blades 3; one end of a movable rod A4, a movable rod B5 and a movable rod C6 is provided in the expansion joint 7 through a rotating shaft, and the rotating shaft can be driven by a power source; the other ends of the movable rods A4, B5 and C6 are provided on the splitter blades 10; the rotation of the rotating shaft drives the movable rods A4, B5 and C6 to rotate, thereby expanding and retracting the splitter blades 10; an external computer 15 is used to process data and send signals.

[0029] In the above solution, the splitter blade 10 is made of flexible material.

[0030] In the above solution, a micro pore water pressure sensor 8 is provided on the suction surface of the main blade 3 ; the micro pore water pressure sensor 8 is used to monitor the water pressure change in the flow channel and transmit the electrical signal to the computer 15 .

[0031] In the above solution, the height of the splitter blade 10 is half of the height of the main blade 3 .

[0032] In the above solution, the expansion joint 7 is located in the middle of the adjacent main blades 3 on the impeller hub 2 .

[0033] In the above solution, the movable rod A4, the movable rod B5 and the movable rod C6 are capable of extension and retraction.

[0034] In the above solution, the shaft connection portion 1, the main blades 3 and the impeller hub 3 are integrally formed.

[0035] The working method of the splitter blade device for suppressing large-scale stall vortex in a mixed flow pump is as follows: after the splitter blade device 10 is installed in the mixed flow pump, water and electricity are supplied. At the beginning of operation, the splitter blade 10 is retracted into the expansion joint 7, and the micro pore water pressure sensor 8 transmits data to the computer 15 for analysis. When the calculated pressure coefficient |C P When |>0.05, the computer 15 issues an instruction to expand the splitter blades 10. After receiving the instruction, the movable rods A4, B5, and C6 rotate counterclockwise and extend, driving the splitter blades 10 to expand, disrupting the flow field in the impeller flow channel. At the same time, the micro pore water pressure sensor 8 continues to transmit data to the computer 15 for analysis. When the pressure coefficient |C P When |>0.02, the computer 15 issues a command to retract the splitter blades 10. After receiving the command, the movable rods A4, B5, and C6 in the impeller expansion joint 7 rotate and retract clockwise, driving the splitter blades 10 to retract into the expansion joint 7.

[0036] A splitter blade device for suppressing large-scale stall vortices in a mixed-flow pump comprises: a shaft connection portion 1 for mounting on a main shaft; an impeller hub 2 mounted on the outside of the shaft connection portion 1; a plurality of main blades 3 circumferentially arranged on the outside of the impeller hub 2; expansion joints 7 provided on the impeller hub 2 and evenly spaced between the main blades 3; a movable rod A4 mounted inside the impeller hub 2; a movable rod B5 mounted inside the impeller hub 2; a movable rod C6 mounted inside the impeller hub 2; a plurality of splitter blades 10, the same in number as the main blades 3, having a height of 1 / 2 that of the main blades 3, circumferentially arranged between two main blades 3, and made of flexible material; a micro-pore water pressure sensor 8 connected to a computer 15 via a micro-pore water pressure sensor signal line 9; and mounted on the suction surface of the main blade 3; a slip ring 14 mounted at the end of the main shaft 13; a computer 15, a peripheral device, for processing data and sending signals, wherein the movable rods A4, B5, and C6 are connected to the computer 15 via an movable rod signal line 11.

[0037] Combined with attachment Figure 5 As shown, the shaft connection part 1, the main blades 3, and the impeller hub 2 are integrally formed.

[0038] Combined with attachment Figure 5 As shown, the micro pore water pressure sensor 8 is installed on the outer side of the suction surface of each main blade 3 to monitor the water pressure changes in the flow channel and send the monitored data to the computer 15 for analysis.

[0039] Combined with attachment Figure 2 As shown, the expansion joint 7 is provided on the outside of the impeller hub 2 and is used for installing the movable rod A4, the movable rod B5, the movable rod C6 and placing the splitter blade 10. Figure 4 As shown, the splitter blades 10 are made of flexible material and are unfolded when diversion is required to disrupt the flow field of the flow channel. After the flow channel is unblocked, they are retracted into the expansion joint 7 on the impeller hub 2.

[0040] Combined with attachment Figure 1 As shown, the movable rod A4, the movable rod B5 and the movable rod C6 are installed inside the impeller hub 2. The three rods are fixedly connected to the edges of the splitter blades 10 respectively, and control the expansion and contraction of the splitter blades 10 at the same time. When the movable rods receive the expansion signal of the splitter blades 10, they rotate counterclockwise at the same time and extend the rods to expand the splitter blades 10. When they receive the contraction signal of the splitter blades 10, the three rods rotate clockwise at the same time and contract the rods to contract the splitter blades 10 to Figure 4 Status shown.

[0041] Combined with attachment Figure 1 As shown, the computer 15 analyzes the data sent by the micro pore water pressure sensor 8 and calculates the pressure coefficient P is the transient static pressure value of each flow channel, is the average static pressure value, when |CP When |>0.05, the computer 15 sends a signal to expand the splitter blade 10 through the signal line 11, and the movable rods A4, B5, and C6 drive the splitter blade 10 to expand. The micro pore water pressure sensor 8 continues to transmit data to the computer 15. When the pressure coefficient |C P When |<0.02, the computer sends a signal to retract the splitter blade 10, and the movable rods A4, B5, and C6 retract the splitter blade 10 to the expansion joint 7. Figure 4 Status shown.

[0042] The working process of a splitter blade device for suppressing large-scale stall vortex in a mixed flow pump is described in detail. The specific process is as follows:

[0043] After the splitter blade device is installed in the mixed flow pump, water and electricity are supplied. At the beginning of operation, the splitter blade 10 is retracted into the expansion joint 7, and the micro pore water pressure sensor 8 transmits data to the computer 15 for analysis. When the calculated pressure coefficient |C P |>0.05, the computer 15 issues an instruction to expand the splitter blade 10. After receiving the instruction, the movable rods A4, B5, and C6 in the impeller expansion joint 7 rotate counterclockwise and extend, driving the splitter blade 10 to expand, disrupting the flow field in the impeller flow channel. At the same time, the micro-pore water pressure sensor 8 continues to transmit data to the computer 15 for analysis. When the pressure coefficient |C P When |>0.02, the computer 15 issues a command to retract the splitter blades 10. After receiving the command, the movable rods A4, B5, and C6 in the impeller expansion joint 7 rotate and retract clockwise, driving the splitter blades 10 to retract into the expansion joint 7.

[0044] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0045] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. A splitter blade device for suppressing large-scale stall vortices in a mixed flow pump, characterized in that: The invention comprises a shaft connection part (1), an impeller hub (2) and a plurality of main blades (3); the shaft connection part (1) is mounted on the main shaft (13), the impeller hub (2) is mounted on the shaft connection part (1), and the main blades (3) are circumferentially arranged on the impeller hub (2); a plurality of expansion joints (7) are provided on the impeller hub (2), and the number of the expansion joints (7) is the same as the number of the main blades (3); a movable rod A (4), a movable rod B (5) and one end of a movable rod C (6) are arranged in the expansion joint (7) through a rotating shaft, and the rotating shaft can be driven by a power source; the other ends of the movable rod A (4), the movable rod B (5) and the movable rod C (6) are arranged on the splitter blade (10); the rotating shaft rotates to drive the movable rod A (4) ), movable rod B (5) and movable rod C (6) rotate to expand and retract the diverter blade (10); the peripheral computer (15) is used to process data and send signals; the diverter blade (10) is made of flexible material; a micro pore water pressure sensor (8) is provided on the suction surface of the main blade (3); the micro pore water pressure sensor (8) is used to monitor the water pressure change in the flow channel and transmit the electrical signal to the computer (15); after the diverter blade (10) device is installed in the mixed flow pump, water and electricity are turned on, and at the beginning of operation, the diverter blade (10) is retracted into the expansion joint (7), and the micro pore water pressure sensor (8) transmits data to the computer (15) for analysis to calculate the pressure coefficient P is the transient static pressure value of each flow channel, is the average static pressure value, when the calculated pressure coefficient |C P When |>0.05, the computer (15) issues an instruction to expand the splitter blade (10). After receiving the instruction, the movable rod A (4), movable rod B (5), and movable rod C (6) rotate counterclockwise and extend, driving the splitter blade (10) to expand, disrupting the flow field in the impeller flow channel. At the same time, the micro pore water pressure sensor (8) continues to transmit data to the computer (15) for analysis. When the pressure coefficient |C P When |<0.02, the computer (15) issues a command to retract the splitter blade (10). After receiving the command, the movable rod A (4), movable rod B (5), and movable rod C (6) in the impeller expansion joint (7) rotate and retract clockwise, driving the splitter blade (10) to retract into the expansion joint (7).

2. The splitter blade device for suppressing large-scale stall vortex in a mixed flow pump according to claim 1, characterized in that: The height of the splitter blade (10) is half the height of the main blade (3).

3. The splitter blade device for suppressing large-scale stall vortex in a mixed flow pump according to claim 1, characterized in that: The expansion joint (7) is located in the middle of adjacent main blades (3) on the impeller hub (2).

4. The splitter blade device for suppressing large-scale stall vortex in a mixed flow pump according to claim 1, characterized in that: The movable rod A (4), the movable rod B (5) and the movable rod C (6) are capable of extension and contraction.

5. The splitter blade device for suppressing large-scale stall vortex in a mixed flow pump according to claim 1, characterized in that: The shaft connection portion (1), main blades (3) and impeller hub (2) are integrally formed.

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