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

Abstract

The invention belongs to the related field of pump test devices, and discloses an integrated solid-liquid two-phase flow centrifugal pump PIV test bench. The test bed is composed of a solid-liquid two-phase recycling system and a PIV test system. Through the integrated arrangement of the circulating water tank, the circulating pipeline, the particle recovery pipeline and the test pump, the structure of the test bench is more compact, and the occupied space required by the test bench is greatly reduced. A water absorber and a particle recoverer in the water tank are respectively connected with a circulation pipeline and a particle recovery pipeline, so that circulation and recovery of particles in the system are realized; the funnel-shaped solid-liquid two-phase mixing cavity enables two-phase flowing and mixing to be more uniform; the vertical arrangement of the inlet pipeline effectively solves the problem of deposition of solid particles in the inlet pipeline due to gravity action.

Description

Technical Field

[0001] The invention relates to the field of solid-liquid two-phase flow tests in centrifugal pumps, and in particular to an integrated solid-liquid two-phase flow PIV test bench for centrifugal pumps. Background Art

[0002] Centrifugal pumps have excellent performance and a wide range of applications. In the industrial field, they often need to transport solid-liquid two-phase media. Compared with single-phase flow, the interaction of two-phase media makes the flow in the pump more complex and uncertain. High-speed photography and PIV and other visualization test technologies are often used to study the two-phase flow in centrifugal pumps. Existing visualization test benches for solid-liquid two-phase flow centrifugal pumps mostly adopt the form of separate arrangement of test pumps and circulating water tanks, which are connected by a circulating pipeline to form a complete flow circulation loop. This leads to the test bench occupying too much space and increasing the cost of the test. The solid particle delivery and recovery device further increases the complexity of the test device. In addition, the inlet pipelines of existing solid-liquid two-phase flow test benches are mostly placed horizontally. When the density of solid particles is large, the particles will settle downward due to gravity, and stratification will occur in the pipeline, resulting in uneven distribution of solid-liquid two-phase media entering the pump, which increases the randomness of the test shooting. Summary of the invention

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

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

[0005] An integrated solid-liquid two-phase flow centrifugal pump PIV test bench, consisting 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 dispenser, a circulation water tank, a test pump, a circulation pipeline and a particle recovery pipeline;

[0007] The test pump is placed at the bottom of the circulating water tank, the motor is fixed above the circulating water tank through a motor frame and drives the test pump to rotate through a coupling, and a shaft encoder and a speed torque meter are arranged between the motor and the circulating water tank;

[0008] A water absorber, a particle recovery device and an energy unloading pipeline are arranged inside the circulating water tank; a resistance disk with a porous structure is arranged inside the water absorber, and the resistance disk divides the water absorber into a cylindrical water absorption chamber and a funnel-shaped mixing chamber; the outlet of the mixing chamber of the water absorber is connected with the inlet of the test pump through an inlet pipeline; the outlet pipeline of the test pump is connected with the circulation pipeline and the particle recovery pipeline through a three-way pipe, wherein the other end of the circulation pipeline is connected to one end of the energy unloading pipeline, and the other end of the energy unloading pipeline is connected to the mixing chamber of the water absorber through the resistance disk; the other end of the particle recovery pipeline is connected to the particle recovery device and extends into the interior;

[0009] The particle dispenser is fixed above the circulating water tank and connected to the mixing chamber of the water absorber through a pipeline. A first valve is provided on the pipeline to control the addition of particles;

[0010] The PIV test system consists 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 facing the test pump; the synchronous controller is electrically connected to 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] The inlet pipeline of the test pump is also provided with an inlet pressure gauge; an outlet pressure gauge and a flow meter are provided between the outlet pipeline of the test pump and the tee pipe;

[0013] A second valve is arranged on the circulation pipeline; by controlling the flow rate of the second valve, the solid-liquid two-phase medium is transported to the energy unloading pipeline.

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

[0015] The wall of the water absorption chamber of the water absorber is provided with circular holes along the circumferential direction and a filter screen is installed. The liquid phase in the circulating water tank enters the water absorption chamber through the circular holes, and then enters the mixing chamber after being rectified by the resistance disk.

[0016] The particle collector is provided with a particle filter screen inside, and the wall surface is provided with circular holes for liquid phase exchange. The solid-liquid two-phase medium enters the particle collector 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 circular holes on the wall surface.

[0017] The wall of the energy unloading pipeline is provided with a slit along the flow direction, the slit width is smaller than the particle diameter, and 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 unloading; a small part of the high-pressure liquid flow carries the particles into the mixing chamber to mix with the low-pressure liquid flow.

[0018] The integrated solid-liquid two-phase flow centrifugal pump PIV test bench described in the present invention can not only conduct tests on the internal flow field and external characteristics of the solid-liquid two-phase flow centrifugal pump, but also conduct various tests on single-phase flow. It is a multifunctional test bench suitable for multiple working conditions. The test bench realizes the circulation and recovery of particles in the pipeline by arranging the circulation pipeline and the particle recovery pipeline. In addition, the arrangement of the energy unloading pipeline and the resistance disk can maintain the stability of the inlet conditions of the test pump; the funnel-type structure of the mixing chamber can ensure that the particles enter the inlet pipeline more evenly; the vertical placement of the inlet pipeline avoids the sedimentation of particles due to gravity; the high-speed camera is arranged below the impeller to ensure that the complete impeller flow channel is captured.

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

[0020] (1) The integrated piping and water tank layout makes the test bench more compact and reduces the test bench footprint.

[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 pipelines and particle recovery pipelines, which reduce the number of particles required while also achieving the purpose of particle circulation and recovery.

[0023] (4) The arrangement of the energy unloading pipeline and the resistance plate ensures the stability of the pump inlet conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is an integrated solid-liquid two-phase flow centrifugal pump PIV test bench described in the present invention.

[0025] Figure 2 Left side view of the test device.

[0026] Figure 3 Schematic diagram of the water absorber structure.

[0027] Description of reference numerals:

[0028] 1-motor; 2-motor frame; 3-coupling; 4-axis encoder; 5-speed torque meter; 6-particle dispenser; 7-first valve; 8-circulating water tank; 9-water absorber; 10-resistance plate; 11-inlet pipeline; 12-inlet pressure gauge; 13-test pump; 15-outlet pressure gauge; 16 flow meter; 17-tee pipe; 18-circulation pipeline; 19-particle recovery pipeline; 20-second valve; 21-third valve; 22-particle recovery device; 23-energy unloading pipeline; 24-high-speed camera; 25-synchronous controller; 26-laser source; 27-computer. Specific implementation plan

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0030] Example 1

[0031] like Figure 1 to Figure 2 As shown, the integrated solid-liquid two-phase flow centrifugal pump PIV test bench described in the present invention is composed of a solid-liquid two-phase circulation recovery system and a PIV test system. The solid-liquid two-phase circulation recovery system includes a particle dispenser 6, an inlet pipeline 11, a test pump 13, a circulating water tank 8, a circulating pipeline 18, and a particle recovery pipeline 19. The test pump 13 is connected to the motor 1 through a coupling 3, and the motor is fixed above the circulating water tank 8 through a motor frame; a shaft encoder 4 and a speed 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 particle dispenser 6 is fixed above the circulating water tank 8 and dispenses solid particles 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 provided with a water absorber 9, a particle recovery device 22 and an energy unloading pipeline 23. A porous resistance disk 10 is provided inside the water absorber 9; the resistance disk 10 divides the water absorber into a water absorption chamber and a mixing chamber; the wall of the water absorption chamber is provided with circular holes along the circumferential direction and a filter is installed to prevent solid particles from flowing out of the circulating pipeline; the outlet of the mixing chamber of the water absorber 9 is connected to the inlet of the test pump 13 through an inlet pipeline 11, and an inlet pressure gauge 12 is provided 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 provided between the test pump 13 and the three-way pipe 17. The other end of the circulation pipeline 18 is connected to one end of the energy unloading pipeline 23, and the other end of the energy unloading pipeline 23 is connected to the mixing chamber of the water absorber 9 through the resistance disk 10; the other end 19 of the particle recovery pipeline extends into the particle recovery device 22, and a filter is provided in the particle recovery device 22 to filter the solid-liquid two-phase medium; the wall of the particle recovery device 22 is provided with a circular hole, and the liquid phase enters the circulation water tank 8 through the circular hole. The wall of the energy unloading pipeline 23 is provided with a gap along the flow direction, and the width of the gap is smaller than the particle diameter, and the high-pressure liquid flow can enter the circulation water tank through the gap.

[0034] The PIV test system consists of 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, and the high-speed camera 24 is arranged below the circulating water tank 8 and facing the test pump 13; the synchronous 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 sides and bottom of the circulating water tank 8 are made of organic glass to facilitate the visual PIV test of the test pump.

[0036] Working method:

[0037] First, according to the test requirements, add a certain amount of solid particles and tracer particles into the particle dispenser 6, start the test pump 13, and when the operation is stable, slowly open the first valve 7 to add the solid particles and tracer particles into the mixing chamber of the water absorber 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 circulation pipeline; after the system operation is stable, adjust the parameters of the PIV test system and conduct the PIV test. After the PIV test is completed, open the third valve 21 and close the second valve 20. 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 operations to obtain the particle image of the solid-liquid two-phase flow field in the pump under different conditions for the test pump 13.

Claims

1. An integrated solid-liquid two-phase flow centrifugal pump PIV test bench, characterized in that: It consists of a solid-liquid two-phase recycling system and a PIV testing system; The solid-liquid two-phase circulation recovery system comprises a particle dispenser (6), a circulation water tank (8), a test pump (13), a circulation pipeline (18) and a particle recovery pipeline (19); The test pump (13) is placed 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 speed torque meter (5) are arranged between the motor (1) and the circulating water tank (8); A water absorber (9), a particle recovery device (22) and an energy unloading pipeline (23) are provided inside the circulating water tank (8); a resistance disk (10) with a porous structure is provided inside the water absorber (9), and the resistance disk (10) divides the water absorber into a cylindrical water absorption chamber and a funnel-shaped mixing chamber; the outlet of the mixing chamber of the water absorber (9) is connected to the inlet of the test pump (13) through the inlet pipeline (11); the outlet pipeline of the test pump (13) is connected to 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 to one end of the energy unloading pipeline (23), and the other end of the energy unloading pipeline (23) is connected to the mixing chamber of the water absorber (9) through the resistance disk (10); the other end of the particle recovery pipeline (19) is connected to the particle recovery device (22) and extends into the interior; The particle dispenser (6) is fixed above the circulating water tank (8) and connected to the mixing chamber of the water absorber (9) through a pipeline. A first valve (7) is provided on the pipeline to control the addition of particles. The PIV test system is composed of 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), and the high-speed camera (24) is arranged below the circulating water tank (8) and facing the test pump (13); the synchronous controller (25) is electrically connected to 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 according to claim 1, characterized in that: 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 also provided on the inlet pipeline of the test pump (13); an outlet pressure gauge (15) and a flow meter (16) are provided 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 according to claim 1, characterized in that: A second valve (20) is provided on the circulation pipeline (18); the solid-liquid two-phase medium is transported to the energy unloading pipeline (23) by controlling the flow rate of the second valve (20); and a third valve (21) is provided 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 absorption chamber of the water absorber (9) is provided with circular holes along the circumferential direction and is provided with a filter screen. The liquid phase in the circulating water tank (8) enters the water absorption chamber through the circular holes and then enters the mixing chamber after being rectified by the resistance disk (10).

6. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench according to claim 1, characterized in that: The particle collector (22) is provided with a particle filter screen inside, and circular holes for liquid phase exchange are opened on the wall.

7. The integrated solid-liquid two-phase flow centrifugal pump PIV test bench according to claim 1, characterized in that: The wall surface of the energy unloading pipeline (23) is provided with a slit along the flow direction, and the width of the slit is smaller than the diameter of the particles.

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