Integrated solid-liquid two-phase flow centrifugal pump PIV test bench

Abstract

The application belongs to the field of pump test device, and discloses an integrated solid-liquid two-phase flow centrifugal pump PIV test table. The test table is composed of a solid-liquid two-phase circulation recovery system and a PIV test system. Through integrated arrangement of a circulating water tank, a circulating pipeline, a particle recovery pipeline and a test pump, the test table structure is more compact, and the required floor space of the test table is greatly reduced. A water suction device and a particle recovery device in the water tank are connected with the circulating pipeline and the particle recovery pipeline respectively, so that the circulation and recovery of particles in the system are realized; the funnel-shaped solid-liquid two-phase mixing cavity makes the two-phase flow mixing more uniform; and the vertical placement of the inlet pipeline effectively solves the deposition of solid particles in the inlet pipeline due to gravity.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of solid-liquid two-phase flow test in centrifugal pump, and particularly relates to an integrated solid-liquid two-phase flow centrifugal pump PIV test bench. BACKGROUND

[0002] The centrifugal pump has excellent performance and wide application range, and often needs to face the delivery of solid-liquid two-phase medium in the industrial field. Compared with single-phase flow, the interaction of two-phase medium makes the flow in the pump more complex and uncertain. The high-speed photography and PIV and other visualization test technologies are often used for research on the two-phase flow in the centrifugal pump. The existing solid-liquid two-phase flow centrifugal pump visualization test bench often adopts the form that the test pump and the circulating water tank are arranged separately, and the two are connected through the circulating pipeline to form a complete flow circulation loop, which leads to that the test bench occupies too large area and increases the test cost, and the solid particle feeding and recovery device further increases the complexity of the test device. In addition, the inlet pipeline of the existing solid-liquid two-phase flow test bench is often horizontally placed, and when the solid particle density is large, the particles will be deposited downward due to the gravity, and stratification occurs in the pipeline, which leads to that the solid-liquid two-phase medium entering the pump is not uniform, and the randomness of the test shooting is increased. SUMMARY

[0003] The purpose of the present application is to provide a solid-liquid two-phase centrifugal pump internal flow field visualization test device which has simpler structure, smaller area, and more uniform solid-liquid two-phase medium at the pump inlet.

[0004] The specific scheme of the present application is as follows:

[0005] An integrated solid-liquid two-phase flow centrifugal pump PIV test bench is composed of a solid-liquid two-phase circulation recovery system and a PIV test system.

[0006] The solid-liquid two-phase circulation recovery system includes a particle feeder, a circulating water tank, a test pump, a circulating pipeline and a particle recovery pipeline.

[0007] The test pump is placed at the bottom of the circulating water tank, the motor is fixed on the circulating water tank through the motor bracket and drives the test pump to rotate through the coupling, and the shaft encoder and the rotation speed and torque instrument are arranged between the motor and the circulating water tank.

[0008] The water suction device, the particle recovery device and the energy dissipation pipeline are arranged in the circulating water tank; the water suction device is internally provided with a porous resistance disc which divides the water suction device into a cylindrical water suction cavity and a funnel-shaped mixing cavity; the mixing cavity outlet of the water suction device is communicated with the inlet of the test pump through an inlet pipeline; the outlet pipeline of the test pump is connected with a circulating pipeline and a particle recovery pipeline through a three-way pipe, wherein the other end of the circulating pipeline is connected with one end of the energy dissipation pipeline, and the other end of the energy dissipation pipeline is communicated with the mixing cavity of the water suction device through the resistance disc; the other end of the particle recovery pipeline is connected with the particle recovery device and extends into the particle recovery device;

[0009] The particle feeder is fixed above the circulating water tank and connected to the mixing cavity of the water suction device through a pipeline, and a first valve is arranged on the pipeline to control the addition of particles.

[0010] The PIV test system is composed of a high-speed camera, a synchronous controller, a laser source and a computer; the laser source is arranged on the side of the circulating water tank and perpendicular to the outlet of the test pump, and the high-speed camera is arranged below the circulating water tank and directly opposite to the test pump; the synchronous controller is electrically connected with the shaft encoder, the high-speed camera and the laser source.

[0011] The test pump is made of organic glass; the side and bottom of the circulating water tank are made of organic glass to facilitate the visual PIV test of the test pump.

[0012] An inlet pressure gauge is further arranged on the inlet pipeline of the test pump; an outlet pressure gauge and a flow meter are arranged between the outlet pipeline of the test pump and the three-way pipe;

[0013] A second valve is arranged on the circulating pipeline; by controlling the flow size of the second valve, the solid-liquid two-phase medium is delivered to the energy dissipation pipeline.

[0014] A third valve is arranged on the particle recovery pipeline.

[0015] The wall surface of the water suction cavity of the water suction device is provided with a circular hole in the circumferential direction and is installed with a filter screen; the liquid phase in the circulating water tank enters the water suction cavity through the circular hole and then flows into the mixing cavity through the resistance disc;

[0016] The particle recovery device is internally provided with a particle filter screen, and the wall surface is provided with a circular hole for liquid exchange; the solid-liquid two-phase medium enters the particle recovery device through the particle recovery pipeline, the solid particles are retained in the filter screen, and the liquid phase enters the circulating water tank through the wall surface circular hole.

[0017] The wall surface of the energy dissipation pipeline is provided with a slit in the flow direction, and the slit width is smaller than the particle diameter; the high-pressure liquid flow can enter the circulating water tank through the slit; most of the high-pressure liquid flow flows into the circulating water tank through the slit to achieve the purpose of energy dissipation; a small part of the high-pressure liquid flow carries particles into the mixing cavity and mixes with the low-pressure liquid flow.

[0018] The integral solid-liquid two-phase flow centrifugal pump PIV test bench can not only carry out the test of the inner flow field and the outer characteristics of the solid-liquid two-phase flow centrifugal pump, but also can carry out various tests of single-phase flow, and is a multifunctional test bench suitable for multiple working conditions. The circulation and recovery of particles in the pipeline are realized through the arrangement of the circulation pipeline and the particle recovery pipeline. In addition, the arrangement of the energy removal pipeline and the resistance disc can maintain the stability of the inlet condition of the test pump; the funnel structure of the mixing chamber can ensure that the particles enter the inlet pipeline more uniformly; the vertical arrangement of the inlet pipeline can avoid the deposition of particles due to gravity; and the high-speed camera arranged below the impeller can ensure that the complete impeller flow passage is shot.

[0019] Compared with the prior art, the advantages of the present application are that:

[0020] (1) The integral pipeline and water tank arrangement make the test bench more compact, reducing the floor space of the test bench.

[0021] (2) The vertical arrangement of the inlet pipeline effectively reduces the deposition of particles and improves the uniformity of the solid-liquid two-phase flow entering the pump.

[0022] (3) There are independent solid-liquid two-phase flow circulation pipeline and particle recovery pipeline, which reduces the required number of particles and also achieves the purpose of particle circulation and recovery.

[0023] (4) The arrangement of the energy removal pipeline and the resistance disc ensures the stability of the pump inlet condition. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 The present application relates to an integral solid-liquid two-phase flow centrifugal pump PIV test bench.

[0025] Fig. 2 It is a left view of the test device.

[0026] Fig. 3 It is a schematic view of the water suction device structure.

[0027] BRIEF DESCRIPTION OF DRAWINGS:

[0028] 1-motor; 2-motor frame; 3-coupling; 4-shaft encoder; 5-rotational speed and torque instrument; 6-particle feeder; 7-first valve; 8-circulation water tank; 9-water suction device; 10-resistance disc; 11-inlet pipeline; 12-inlet pressure gauge; 13-test pump; 15-outlet pressure gauge; 16-flow meter; 17-three-way pipe; 18-circulation pipeline; 19-particle recovery pipeline; 20-second valve; 21-third valve; 22-particle recovery device; 23-energy removal pipeline; 24-high-speed camera; 25-synchronous controller; 26-laser source; 27-computer. DETAILED EMBODIMENT

[0029] The present invention will now be described in further detail with reference to the accompanying drawings:

[0030] Example 1

[0031] like Figs. 1-2 As shown, the integrated solid-liquid two-phase flow centrifugal pump PIV test bench of the present invention consists of a solid-liquid two-phase circulation recovery system and a PIV testing system. The solid-liquid two-phase circulation recovery system includes a particle feeder 6, an inlet pipe 11, a test pump 13, a circulating water tank 8, a circulation pipe 18, and a particle recovery pipe 19. The test pump 13 is connected to a motor 1 via a coupling 3, and the motor is fixed above the circulating water tank 8 by a motor frame. A shaft encoder 4 and a speed and torque meter 5 are connected between the motor 1 and the test pump 13, both of which are fixed on the motor frame.

[0032] The pellet dispenser 6 is fixed above the circulating water tank 8 and feeds solid pellets into the mixing chamber of the water absorber 9 through a pipeline. A first valve 7 is provided on the pipeline.

[0033] The circulating water tank 8 is equipped with a water suction device 9, a particle recovery device 22, and an energy dissipation pipeline 23. The water suction device 9 has a porous resistance plate 10 inside; the resistance plate 10 divides the water suction device into a water suction chamber and a mixing chamber; the wall of the water suction chamber has circular holes along the circumferential direction and is equipped with a filter screen to prevent solid particles from flowing out of the circulating pipeline; the outlet of the mixing chamber of the water suction device 9 is connected to the inlet of the test pump 13 through an inlet pipeline 11, and an inlet pressure gauge 12 is installed on the inlet pipeline 11; the outlet pipeline of the test pump 13 is connected to the circulating pipeline 18 with a second valve 20 and the particle recovery pipeline 19 with a third valve 21 through a three-way pipe 17; an outlet pressure gauge 15 and a flow meter 16 are installed between the test pump 13 and the three-way pipe 17. The other end of the circulation pipe 18 is connected to one end of the energy-discharging pipe 23, and the other end of the energy-discharging pipe 23 is connected to the mixing chamber of the water absorber 9 through the resistance plate 10; the other end 19 of the particle recovery pipe extends into the particle recovery unit 22, where a filter screen is installed to filter the solid-liquid two-phase medium; the particle recovery unit 22 has a circular hole on its wall, through which the liquid phase enters the circulating water tank 8. The energy-discharging pipe 23 has a slit on its wall along the flow direction, the slit width of which is smaller than the particle diameter, allowing the high-pressure liquid flow to enter the circulating water tank through the slit.

[0034] The PIV testing system consists of a high-speed camera 24, a synchronization controller 25, a laser source 26, and a computer 27. The laser source 26 is arranged on the side of the circulating water tank 8 and perpendicular to the outlet of the test pump 13. The high-speed camera 24 is arranged below the circulating water tank 8 and directly facing the test pump 13. The synchronization controller 25 is electrically connected to the shaft encoder 4, the high-speed camera 24, and the laser source 26.

[0035] The test pump 13 is made of organic glass; the side and bottom of the circulating water tank 8 are made of organic glass to facilitate the PIV test of the test pump.

[0036] Working mode:

[0037] First, according to the test requirements, a certain amount of solid particles and tracer particles are added in the particle feeder 6, the test pump 13 is started, and when the operation is stable, the first valve 7 is slowly opened to add the solid particles and tracer particles into the mixing chamber of the water suction device 9; at this time, the second valve 20 is opened, the third valve 21 is closed, and the two-phase flow medium circulates in the circulating pipeline; after the system runs stably, the parameters of the PIV test system are adjusted, and the PIV test is carried out. After the PIV test is completed, the third valve 21 is opened and the second valve 20 is closed, at this time, the solid-liquid two-phase flow enters the particle recovery device 22 through the particle recovery pipeline to recover the particles. Change the test conditions and repeat the above operation to obtain the particle image of the solid-liquid two-phase flow field in the test pump 13 under different working conditions.

Claims

1. An integrated solid-liquid two-phase flow centrifugal pump PIV test bench, characterized in that, The system comprises a solid-liquid two-phase circulation recovery system and a PIV test system; The solid-liquid two-phase circulation recovery system comprises a particle feeder (6), a circulating water tank (8), a test pump (13), a circulating pipeline (18) and a particle recovery pipeline (19). The test pump (13) is arranged at the bottom of the circulating water tank (8), the motor (1) is fixed above the circulating water tank (8) through a motor frame and drives the test pump (13) to rotate through a coupling (3), and a shaft encoder (4) and a rotating speed and torque instrument (5) are further arranged between the motor (1) and the circulating water tank (8). The circulating water tank (8) is internally provided with a water suction device (9), a particle recovery device (22) and a de-energizing pipeline (23); the water suction device (9) is internally provided with a porous resistance disc (10), the resistance disc (10) divides the water suction device into a cylindrical water suction cavity and a funnel-shaped mixing cavity; the mixing cavity outlet of the water suction device (9) is communicated with the inlet of the test pump (13) through an inlet pipeline (11); the outlet pipeline of the test pump (13) is connected with the circulating pipeline (18) and the particle recovery pipeline (19) through a three-way pipe (17), wherein the other end of the circulating pipeline (18) is connected with one end of the de-energizing pipeline (23), the other end of the de-energizing pipeline (23) is communicated with the mixing cavity of the water suction device (9) through the resistance disc (10), and the other end of the particle recovery pipeline (19) is connected with the particle recovery device (22) and extends into the particle recovery device (22); the de-energizing pipeline (23) is provided with a slit along the flow direction on the wall surface, and the slit has a width smaller than the diameter of the particle. The particle feeder (6) is fixed above the circulating water tank (8) and connected to the mixing cavity of the water suction device (9) through a pipeline, and a first valve (7) is arranged on the pipeline to control the addition of particles. The PIV test system comprises a high-speed camera (24), a synchronous controller (25), a laser source (26) and a computer (27); the laser source (26) is arranged on the side of the circulating water tank (8) and perpendicular to the outlet of the test pump (13), the high-speed camera (24) is arranged below the circulating water tank (8) and directly opposite to the test pump (13), and the synchronous controller (25) is electrically connected with the shaft encoder (4), the high-speed camera (24) and the laser source (26).

2. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench of claim 1, wherein, The test pump (13) is made of organic glass; the side and bottom of the circulating water tank (8) are made of organic glass.

3. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench according to claim 1, characterized in that, An inlet pressure gauge (12) is further arranged on the inlet pipeline of the test pump (13); an outlet pressure gauge (15) and a flowmeter (16) are arranged between the outlet pipeline of the test pump (13) and the three-way pipe (17).

4. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench of claim 1, wherein, A second valve (20) is arranged on the circulating pipeline (18); the solid-liquid two-phase medium is delivered to the de-energizing pipeline (23) by controlling the flow size of the second valve (20); and a third valve (21) is arranged on the particle recovery pipeline (19).

5. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench according to claim 1, characterized in that, The wall surface of the water suction cavity of the water suction device (9) is provided with a circular hole along the circumferential direction and is installed with a filter screen, and the liquid phase in the circulating water tank (8) enters the water suction cavity through the circular hole and then enters the mixing cavity after being rectified by the resistance disc (10).

6. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench of claim 1, wherein, The particle recovery device (22) is internally provided with a particle filter screen and is provided with a circular hole on the wall surface for liquid phase exchange.

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