An automatic control test device for interaction between settling balls

Abstract

The present invention discloses an automatic control test device for the interaction of settling balls, which includes a horizontal test tube, a dye ball, a synchronous ball-dropping device, a high-speed camera system, a test ball collection device, a water collecting funnel, a return water pipeline, a water reservoir, a variable frequency water pump, a water inlet pipe, a water storage tank, an overflow gate, and a rectifier plate. The dye ball enters the test tube through the synchronous ball-dropping device and moves and settles with the flow; the high-speed camera system captures the dye ball's settling motion image in real time, obtains the dye ball's motion trajectory through image processing, and analyzes the interaction during the sedimentation process; the test ball collection device captures the dye ball downstream of the test tube, and the water flows into the water reservoir through the return water pipeline and is then pumped into the water storage tank by a variable frequency pump; the overflow gate is raised and lowered according to the head difference between the water surface of the water tank and the center of the test tube, and the excess water overflows through the gate to ensure uniform flow in the test tube. This device can simulate solid-liquid two-phase flow and observe the movement trajectory of multiple spheres with the water flow and the interaction when settling, with high precision, low cost, and simple operation.

Description

Technical Field

[0001] The invention belongs to the fields of water conservancy engineering and fluid mechanics, and particularly relates to an automatic control test device for interaction of settling balls. Background Art

[0002] During sediment settling, sediment is affected not only by the resistance of the water flow but also by the influence of surrounding sediment particles. The settling of a single sediment particle causes the surrounding water to flow downward. At this point, if other sediment particles are nearby, the particles themselves are less likely to deform relative to the water, creating resistance to the downward-flowing water and preventing it from flowing freely. This effectively increases the viscosity of the liquid. Due to the continuous action of the water flow, the sinking sediment causes the same volume of water to rise, resulting in a small upward flow rate. Simultaneously, the concentration of surrounding sediment particles increases the specific gravity of the water. These factors all affect the sediment settling rate, thereby affecting its movement in the water.

[0003] Sediment sedimentation is often treated as spheres in sediment studies, but until now, there has been a lack of experimental equipment that can systematically observe the interaction between two or more spheres during sedimentation. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention proposes an automatic control test device for interaction between sinking balls. The specific technical solution is as follows:

[0005] An automatic control test device for interaction of settling balls, comprising a horizontal test tube, a dye ball, a synchronous ball dropping device, a high-speed camera system, a test ball collecting device, a water collecting funnel, a return water pipeline, a water reservoir, a variable frequency water pump, a water inlet pipe, a water storage tank, an overflow gate, and a rectifier plate;

[0006] The water tank is located above the water reservoir; the variable frequency water pump is located in the water reservoir and is connected to the bottom of the water tank through the water inlet pipe; the rectifier plate is located inside the water tank and is used to rectify the water entering the water tank; the overflow gate is located on the side wall of the water tank; the horizontal test pipe is connected to the bottom of the side of the water tank; the synchronous ball falling device is fixed above the horizontal test pipe and is close to the inlet of the horizontal test pipe; the dye ball is located in the synchronous ball falling device; the test ball collecting device is located near the water outlet of the horizontal test pipe and is used to collect the dye balls; the water collecting funnel is connected to the water outlet of the horizontal test pipe, and the bottom is connected to the water reservoir through the return pipe; the high-speed camera system is located below the horizontal test pipe and is used to shoot the movement trajectories of multiple dye balls in the horizontal test pipe during the test process.

[0007] Furthermore, the synchronous ball-dropping device consists of two sets, which are arranged vertically and in a T-shape on the central axis of the horizontal test tube; each set of the synchronous ball-dropping device includes two ball-dropping tubes, a hollow sleeve rod, a button and a spring; the hollow sleeve rod is arranged between the two ball-dropping tubes, the spring is located in the hollow sleeve rod, the bottom of the button is inserted into the hollow sleeve rod, and the head is exposed from the hollow sleeve rod, which is a pressing part; the button includes two elastic and completely thin rods, and when not pressed, the elastic and completely thin rods penetrate into the ball-dropping tubes on both sides, and the dye ball located in the ball-dropping tube is supported on the elastic and completely thin rods.

[0008] Furthermore, the horizontal test tube is embedded in the groove of the test ball collecting device.

[0009] Furthermore, the rectifier plate is a porous rectifier plate, and there are two types. The water-permeable holes on the two rectifier plates are arranged at different heights in the vertical direction; the two types of rectifier plates are arranged in parallel in the water tank in an alternating manner, so that the water-permeable holes on the plate surface are staggered in space, ensuring a good rectification effect.

[0010] Furthermore, the test ball collecting device is a rectangular parallelepiped, and its length, width and height satisfy the following relationship:

[0011]

[0012] Among them, L P is the length of the test ball collection device, H is the height, R is half of the width, and is also the inner radius of the horizontal test tube, ω min is the minimum sedimentation velocity of the dye ball, V c is the maximum test flow rate.

[0013] A test method based on an automatic test device, the method comprising the following steps:

[0014] (1) Place the dye ball in the ball drop tube of the synchronous ball drop device, and the device is in a closed state;

[0015] (2) According to the test flow rate v0, adjust the lifting height h of the overflow gate:

[0016]

[0017] Where R is the inner radius of the horizontal test tube, L is the side length of the square water tank, λ is the loss factor along the way, ζ i , i = 1, 2, 3, ζ1 is the local resistance factor at the inlet, ζ2 is the local resistance factor at the settling ball collection device, and ζ3 is the local resistance factor at the outlet;

[0018] (3) Pour water into the water reservoir, start the variable frequency water pump, and pump the water from the water reservoir into the water tank through the water inlet pipe. After being rectified by the staggered rectifier plates, the water enters the horizontal test pipe to form a uniform flow. After being collected by the water collecting funnel, the water flows back to the water reservoir to form a cycle.

[0019] (4) After the water flow in the horizontal test tube stabilizes, the synchronous ball-dropping device is turned on, and the dye balls automatically fall into the horizontal test tube under the action of gravity and move with the water flow; at the same time, the high-speed camera system records the interaction and movement trajectory between the dye balls in the horizontal test tube in real time, extracts the spatial position and minimum spacing of the two dye balls at different times, and calculates the sedimentation velocity and relative motion velocity vector of the dye balls and the distance between the centers of different dye balls; when the distance between the centers of the two dye balls is always equal to the sum of the radii of the two balls, it is adhesion sedimentation; when the distance between the centers of the two dye balls is always not equal to the sum of the radii of the two balls, it is non-collision sedimentation; the rest is collision sedimentation;

[0020] (5) The dye ball moves to the downstream section of the horizontal test tube and is collected by the dye ball collecting device. The variable frequency water pump is turned off to complete a test.

[0021] The beneficial effects of the present invention are as follows:

[0022] The automatic control test device for the interaction of the settling balls of the present invention utilizes a high-speed camera system combined with image processing technology to simulate solid-liquid two-phase flow, observe the movement trajectories of multiple balls along the water flow and the interaction during settling, and quantitatively analyze the mutual influence between the multiple balls. It has high precision, low cost and simple operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The automatic control test device for the interaction of the settling balls of the present invention utilizes a high-speed camera system combined with image processing technology to simulate solid-liquid two-phase flow, observe the movement trajectories of multiple balls along the water flow and the interaction during settling, and quantitatively analyze the mutual influence between the multiple balls. It has high precision, low cost and simple operation.

[0024] Figure 1 Schematic diagram of the automatic control test device for interaction of settling balls of the present invention;

[0025] Figure 2 Schematic diagram of the synchronous ball falling device.

[0026] Figure 3 Schematic diagram of the T-type arrangement of the synchronized ball-dropping device.

[0027] Figure 4 This is the left side view of the water tank.

[0028] Figure 5 Schematic diagram of two types of rectifier plates.

[0029] In the figure, 1-horizontal test tube, 2-dyed ball, 3-synchronous ball falling device, 4-high-speed camera system, 5-test ball collection device, 6-water collection funnel, 7-return pipe, 8-water reservoir, 9-frequency conversion water pump, 10-water inlet pipe, 11-water storage tank, 12-overflow gate, 13-rectifier plate. DETAILED DESCRIPTION

[0030] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments, and the purpose and effects of the present invention will become more apparent. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0031] like Figure 1-Figure 5 As shown, the automatic control test device for interaction of settling balls of the present invention includes a horizontal test tube 1, a dye ball 2, a synchronous falling ball device 3, a high-speed camera system 4, a test ball collection device 5, a water collecting funnel 6, a return water pipeline 7, a water reservoir 8, a variable frequency water pump 9, a water inlet pipe 10, a water storage tank 11, an overflow gate 12, and a rectifier plate 13.

[0032] The water tank 11 is located above the water reservoir 8; the variable frequency water pump 9 is located in the water reservoir 8 and is connected to the bottom of the water tank 11 through the water inlet pipe 10; the rectifier plate 13 is located inside the water tank 11 and is used to rectify the water entering the water tank 11; the overflow gate 12 is located on the side wall of the water tank 11; the horizontal test pipe 1 is connected to the bottom of the side of the water tank 11; the synchronous ball falling device 3 is fixed above the horizontal test pipe 1 and is close to the inlet of the horizontal test pipe 1; the dye ball 2 is located in the synchronous ball falling device 3; the test ball collecting device 5 is located near the water outlet of the horizontal test pipe 1 and is used to collect the dye balls 2; the water collecting funnel 6 is connected to the water outlet of the horizontal test pipe 1, and the bottom is connected to the water reservoir 8 through the return pipe 7; the high-speed camera system 4 is located below the horizontal test pipe 1 and is used to shoot the movement trajectory of multiple dye balls 2 in the horizontal test pipe 1 during the test process.

[0033] Two sets of synchronized ball-dropping devices 3 are arranged vertically, with the walls of the drop tubes tangent to each other. They are arranged in a T-shape on the central axis of the horizontal test tube 1 and located at the top of the horizontal test tube. Each synchronized ball-dropping device 3 includes two drop tubes 301, a hollow rod 302, a button 303, and a spring 304. The hollow rod 302 is positioned between the two drop tubes 301, and the spring 304 is located within the hollow rod 302. The bottom of the button 303 is inserted into the hollow rod 302, with the top protruding from the hollow rod 302, forming the pressing portion. The button 303 includes two elastic, fully retractable rods. When not pressed, the elastic, fully retractable rods extend deep into the drop tubes 301 on either side, supporting the dye ball 2 within the drop tube 301. Place the two dye balls at the same height. After pressing the button, the thin rod is pulled out from the small hole. Under the action of gravity, the dye balls in the ball drop tube fall into the horizontal test tube from the same height and close distance at the same time, and settle in the turbulent water flow and interact with each other.

[0034] An overflow gate 12 is provided on the water inlet side of the water tank 11. The overflow gate 12 is connected to an automatically controlled lifting system, and the elevation of the top of the overflow gate 12 is controlled by the automatic control system according to the water surface height h. Let R be the diameter of the horizontal test pipe, R be the radius of the horizontal test pipe, v0 be the test set flow rate, v1 be the flow rate of the water in the water tank after turbulence through the turbulence plate, ζ1 be the local resistance factor at the inlet, ζ2 be the local resistance factor at the sedimentation ball collection device, ζ3 be the local resistance factor at the outlet, λ be the loss factor along the way, and L be the side length of the square water tank. Then the cross-sectional areas A0 and A1 of the horizontal test pipe and the water tank are πR respectively. 2 and L 2 ; Then v1=πR 2 v0 / L 2 ; Substitute the Bernoulli equation into the circulatory system

[0035]

[0036] Available When the test flow rate is set to v0, the height to which the overflow gate automatic control device raises the gate top is:

[0037]

[0038] Σξ i It is the sum of the local resistance coefficients at the inlet, the settling ball collection device, and the outlet. When the water level in the tank exceeds the top of the overflow gate, the water automatically overflows from the overflow gate.

[0039] The experimental ball collection device is located in the downstream section of the horizontal experimental pipe and is tangent to the horizontal experimental pipe. Its cross-sectional shape and longitudinal section are as follows: Figure 4 As shown. The test ball collection device is a rectangular parallelepiped with a width of 2R and a height of H. The cross-sectional area of ​​the horizontal test tube is A0 = πR 2, the cross-sectional area of ​​the test ball collection device A1=πR 2 / 2+HL P . Let V c is the maximum flow velocity in the test tube, that is, the water flow velocity at the center of the tube; d is the particle size of the test ball; ω min is the minimum settling velocity of the test ball within the particle size range. Then the maximum flow velocity in the test ball collection device is v = πR 2 v c / (πR 2 / 2+HL P ); the longest settling time of the test ball t = D / ω min The test ball moves with the water flow in the upstream of the horizontal pipe and reaches the downstream collection device. Due to the sudden increase in cross-sectional area and the decrease in flow rate, the test particles will settle into the collection device. When the collection device length L P Equal to the minimum sinking speed ω of the dye ball min and maximum flow rate V c The horizontal distance of the movement in the sedimentation device can ensure that the test ball falls completely into the collection device.

[0040] The high-speed camera system consists of a digital camera, a computer, and image analysis and processing software. The high-speed camera records the movement trajectory of the dye balls in the horizontal test tube in real time and inputs it into the computer in the form of digital images; the image analysis and processing software extracts the spatial position of the center of each dye ball. The eddy flow velocity caused by the motion trajectory and the sedimentation disturbance of the dye ball Calculate the distance between the centers of different chromatic balls and the relative velocity vector Subscripts m and n are the numbers of the chromatin balls. P (t) and distance threshold (d m +d n ) / 2 determines the three types of chromosphere interactions, namely D P (t)≡(d m +d n ) / 2 is the bonding settlement, D P (t)≠(d m +d n ) / 2 is non-collision sedimentation, and the rest is collision sedimentation. Based on the above data, the relationship between the dye-ball interaction and the flow parameters is analyzed.

[0041] The rectifier plates 13 are divided into two types, a and b. The two types of rectifier plates are arranged alternately so that the water-permeable holes on the plate surfaces are distributed alternately in space, thereby ensuring a good rectification effect.

[0042] Water flows smoothly and evenly from the water storage tank into the horizontal test tube 1. An automatically controlled ball-dropping device 2 is provided above the horizontal test tube 1. Multiple test dye balls 3 are placed in the ball-dropping device. Through automatic control, the multiple balls synchronously enter the horizontal test tube and move with the uniform flow. A high-speed camera system 4 captures the movement trajectories of the multiple dye balls and automatically analyzes the interaction between the multiple balls during the sedimentation process. A dye ball collecting device 5 is provided at the downstream end of the horizontal test tube 1. The dye balls 3 automatically fall into the collecting device 5 under the action of gravity. The outlet of the horizontal test tube is connected to the atmosphere. After the water flows from the outlet through the water collecting funnel 6, it automatically flows into the water reservoir 8 through the inclined return pipe 7. A variable frequency water pump 9 is placed at the bottom of the water reservoir to pump water from the water reservoir into the water storage tank 11 through the water inlet pipe 10.

[0043] The working process of the present invention is:

[0044] (1) Two or more dye balls 2 are placed in the ball-dropping tube of the synchronous ball-dropping device 3, and the device is in a closed state.

[0045] (2) According to the test flow rate v0, use the gate automatic control device to adjust the overflow gate 12 to the height h.

[0046] (3) Pour an appropriate amount of water into the water reservoir 8, start the variable frequency water pump 9, and pump the water from the water reservoir into the water tank 11 through the water inlet pipe 10. After being rectified by the staggered rectifier plates 13, the water enters the horizontal test tube 1 to form a uniform flow. After being collected by the water collecting funnel 6, the water flows back to the water reservoir 8 to form a cycle.

[0047] (4) After the water flow in the horizontal test tube 1 stabilizes, the synchronous ball-dropping device 3 is turned on, and the dye balls 2 automatically fall into the horizontal test tube 1 under the action of gravity and move with the water flow; at the same time, the high-speed camera system 11 records the interaction and movement trajectory between the dye balls in the horizontal test tube in real time, extracts the spatial position and minimum distance between the two dye balls at different times, and calculates the sedimentation velocity and relative motion velocity vector of the dye balls and the distance between the centers of different dye balls; when the distance between the centers of the two dye balls is always equal to the sum of the radii of the two balls, it is adhesion sedimentation; when the distance between the centers of the two dye balls is always not equal to the sum of the radii of the two balls, it is non-collision sedimentation; the rest is collision sedimentation;

[0048] (5) The dye ball 2 moves to the downstream section of the horizontal test tube and is collected by the dye ball collecting device 5. The variable frequency water pump 9 is turned off to complete one test.

[0049] Those skilled in the art will understand that the foregoing descriptions are merely preferred embodiments of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art will still be able to modify the technical solutions described in the foregoing examples or substitute equivalents for some of the technical features therein. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the invention shall be included within the scope of protection of the invention.

Claims

1. An automatic control test device for interaction between sinking balls, characterized in that: The device comprises a horizontal test tube (1), a dye ball (2), a synchronous ball-dropping device (3), a high-speed camera system (4), a test ball collecting device (5), a water collecting funnel (6), a return water pipeline (7), a water reservoir (8), a variable frequency water pump (9), a water inlet pipe (10), a water storage tank (11), an overflow gate (12), and a rectifier plate (13); The water storage tank (11) is located above the water reservoir (8); the variable frequency water pump (9) is located in the water reservoir (8) and is connected to the bottom of the water storage tank (11) through the water inlet pipe (10); the rectifier plate (13) is located inside the water storage tank (11) and is used to rectify the water entering the water storage tank (11); the overflow gate (12) is located on the side wall of the water storage tank (11); the horizontal test pipe (1) is connected to the bottom of the side of the water storage tank (11); the synchronous ball falling device (3) is fixed above the horizontal test pipe (1) and is close to the water inlet pipe (10). near the inlet of the horizontal test tube (1); the dye ball (2) is located in the synchronous ball falling device (3); the test ball collecting device (5) is located near the water outlet of the horizontal test tube (1) and is used to collect the dye balls (2); the water collecting funnel (6) is connected to the water outlet of the horizontal test tube (1), and the bottom is connected to the water reservoir (8) through the return pipe (7); the high-speed camera system (4) is located below the horizontal test tube (1) and is used to shoot the movement trajectories of multiple dye balls (2) in the horizontal test tube (1) during the test process.

2. The automatic control test device for interaction of sinking balls according to claim 1, characterized in that: The synchronous ball-dropping device (3) comprises two sets, which are arranged vertically and arranged in a T-shape on the central axis of the horizontal test tube (1); each set of the synchronous ball-dropping device (3) comprises two ball-dropping tubes (301), a hollow sleeve rod (302), a button (303) and a spring (304); the hollow sleeve rod (302) is arranged between the two ball-dropping tubes (301), the spring (304) is located in the hollow sleeve rod (302), the bottom of the button (303) is inserted into the hollow sleeve rod (302), and the head is exposed from the hollow sleeve rod (302), which serves as a pressing part; the button (303) comprises two elastic and completely thin rods, and when not pressed, the elastic and completely thin rods penetrate into the ball-dropping tubes (301) on both sides, and the dye ball (2) located in the ball-dropping tube (301) is supported on the elastic and completely thin rods.

3. The automatic control test device for interaction between sinking balls according to claim 1, characterized in that: The horizontal test tube (1) is embedded in the groove of the test ball collecting device (5).

4. The automatic control test device for interaction between sinking balls according to claim 1, characterized in that: The rectifier plates (13) are multi-hole rectifier plates of two types. The water-permeable holes on the two rectifier plates are arranged at different heights in the vertical direction. The two types of rectifier plates are arranged in parallel in a staggered manner in the water storage tank (11), so that the water-permeable holes on the plate surface are staggered in space, thereby ensuring a good rectification effect.

5. The automatic control test device for interaction between sinking balls according to claim 1, characterized in that: The test ball collecting device (5) is a rectangular parallelepiped, and its length, width and height satisfy the following relationship: Among them, L P is the length of the test ball collecting device (5), H is the height, R is half of the width, and is also the inner radius of the horizontal test tube (1), ω min is the minimum sedimentation velocity of the dye ball, V c is the maximum test flow rate.

6. A test method based on the automatic test device according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: (1) placing the dye ball (2) in the ball drop tube of the synchronous ball drop device (3), while the device is in a closed state; (2) According to the test flow rate v0, adjust the lifting height h of the overflow gate (12): Where R is the inner radius of the horizontal test tube (1), L is the side length of the square water tank, λ is the loss factor along the way, ζ i , i = 1, 2, 3, ζ1 is the local resistance factor at the inlet, ζ2 is the local resistance factor at the settling ball collection device, and ζ3 is the local resistance factor at the outlet; (3) Pour water into the water reservoir (8), start the variable frequency water pump (9), and pump the water from the water reservoir (8) into the water storage tank (11) through the water inlet pipe (10). After being rectified by the staggered rectifier plates (13), the water enters the horizontal test pipe (1) to form a uniform flow. After being collected by the water collecting funnel (6), the water flows back to the water reservoir (8) to form a cycle. (4) After the water flow in the horizontal test tube (1) is stabilized, the synchronous ball-dropping device (3) is turned on, and the dye balls (2) automatically fall into the horizontal test tube (1) under the action of gravity and move with the water flow; at the same time, the high-speed camera system (4) records the interaction and movement trajectory between the dye balls in the horizontal test tube in real time, extracts the spatial position and minimum distance between the two dye balls at different times, and calculates the sedimentation speed and relative movement speed vector of the dye balls and the distance between the centers of different dye balls; when the distance between the centers of the two dye balls is always equal to the sum of the radii of the two balls, it is adhesion sedimentation; when the distance between the centers of the two dye balls is always not equal to the sum of the radii of the two balls, it is non-collision sedimentation; the rest is collision sedimentation; (5) The dye ball (2) moves to the downstream section of the horizontal test pipe and is collected by the test ball collecting device (5). The variable frequency water pump (9) is turned off to complete one test.

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