A bank rock scouring simulation device and method based on continuity principle

Abstract

The application belongs to the technical field of hydraulic engineering, and specifically provides a bank slope rock scour simulation device and method based on the continuity principle, which comprises a scour test section, the scour test section comprises a plurality of unit pipes, one side or both sides of the unit pipe is provided with a rock sample loading interface, the rock sample loading interface is provided with a rock sample mounting port on the side close to the inner wall of the unit pipe, and the rock sample mounting port is provided with a rock sample limiting sheet on the side close to the inside of the unit pipe; the rock sample fixer comprises a fixed cylinder with a closed one end, the fixed cylinder is provided with a compression spring, one end of the compression spring is provided with a rock sample pressing plate which is pressed against the outside of the rock sample, and the fixed cylinder is threadedly connected with the rock sample loading interface; the downstream of the scour test section is provided with a speed measurement section, the speed measurement section is provided with a flow measurement device; and the device further comprises a water supply mechanism, which is used for supplying water to the scour test section and the speed measurement section to form a circulating waterway. The device realizes the simulation of the rock scour test, is based on the continuity principle, and is convenient for regulating and controlling the flow velocity of the scouring water flow.

Description

Technical Field

[0001] This invention belongs to the field of water conservancy engineering technology, and specifically relates to a device and method for simulating bank slope rock erosion based on the principle of continuity. Background Technology

[0002] During the operation of hydropower projects, the rock mass in the drawdown zone of the riverbank is not only affected by wet-dry cycles but also susceptible to erosion by water flow. The water flow velocity varies at different depths within the same cross-section, resulting in varying erosion intensities and consequently different deterioration effects on the rock mass's physical and mechanical parameters. Utilizing the principle of continuity in fluid mechanics, this experiment simultaneously and quantitatively simulates the erosive effect of erosion intensity on the riverbank soil and rock mass within the same cross-section. This provides guidance for understanding the stability analysis of riverbanks under water flow erosion, compensates for the shortcomings of existing simulated rock erosion test devices, and optimizes experimental methods. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a device and method for simulating rock erosion on bank slopes based on the principle of continuity, so as to realize the simulation of rock erosion test and facilitate the control of the flow velocity of the erosion water based on the principle of continuity.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a slope rock erosion simulation device based on the principle of continuity, including an erosion test section, the erosion test section including several unit tubes, a rock sample loading interface is provided on one or both sides of the unit tube, the rock sample loading interface is used to connect with a rock sample holder, a rock sample installation port is provided on the side of the rock sample loading interface near the inner wall of the unit tube, and a rock sample limiting piece is provided on the side of the rock sample installation port near the inside of the unit tube.

[0005] The rock sample holder includes a fixed cylinder with one end closed, a compression spring inside the fixed cylinder, and a rock sample pressure plate that presses against the outside of the rock sample at one end of the compression spring. The fixed cylinder is threadedly connected to the rock sample loading interface.

[0006] A velocity measuring section is located downstream of the scour test section, and a flow measurement device is installed in the velocity measuring section.

[0007] It also includes a water supply system, which supplies water to the scouring test section and the speed measurement section to form a circulating water path.

[0008] In a preferred embodiment, the channels within the unit tube include a head-end guiding channel, a scour simulation channel, and an end-end dispersing channel connected in sequence, with the rock sample installation port connected to the scour simulation channel.

[0009] In a preferred embodiment, adjacent unit tubes are connected by threads, as are unit tubes at the tail end and the speed measuring section, and unit tubes at the head end and the water supply mechanism.

[0010] In a preferred embodiment, the diameters of the simulated flushing channels of the various unit pipes are different, and the water flow section A at the flushing point of each unit pipe is... i The cross-sectional area of ​​the water passage is smaller than A0 of the speed measurement section.

[0011] In a preferred embodiment, the water supply mechanism includes a water tank device and a water pump supply device. The water tank device includes a water tank, with a drain valve at the outlet and an inlet valve at the inlet. The water pump supply device includes a water pump, with the inlet connected to the outlet of the water tank via a supply pipe, the outlet connected to an outlet pipe, and the outlet pipe connected to the scouring test section. The speed measuring section is connected to the inlet of the water tank.

[0012] In a preferred embodiment, the outlet pipe is a bend.

[0013] In a preferred embodiment, the water tank is a closed water tank with a water inlet and a pressurization hole at the top. The pressurization hole is used to connect to the pipeline of the air compressor. A pressure gauge is provided on one side of the water tank, and the pressure gauge is flush with the center point of the scour surface of the rock sample in the scour test section.

[0014] In a preferred embodiment, the flow measurement device is an electromagnetic flow meter.

[0015] This invention also provides a test method for a bank slope rock erosion simulation device based on the principle of continuity, comprising the following steps:

[0016] S1. Select the number of unit tubes for the scour test section as needed. Connect the unit tubes end to end to form the scour test section. Place a cubic rock sample into the rock sample installation port of each unit tube, so that the test surface of the rock sample is in close contact with the rock sample limiting plate. Install the rock sample holder at the rock sample loading interface. Under the action of the compression spring, the test surface of the rock sample is pressed against one side of the rock sample limiting plate. Repeat the operation to load rock sample into each unit tube.

[0017] S2. Connect the inlet end of the flushing test section to the outlet pipe, connect the outlet end of the flushing test section to the speed measuring section, connect the tail end of the speed measuring section to the inlet of the water tank, and connect the water supply pipe of the water pump supply device to the outlet of the water tank to form a circulation loop.

[0018] S3. Open the water inlet of the water tank to add water to the water tank, so that the circulation loop is full of water, and then close the water inlet;

[0019] S4. Connect the pressure port to the external air compressor, start the water pump to start the internal water circulation, adjust the water pump power according to the flow velocity measured in the velocity measurement section to meet the required simulated scouring flow velocity, start the external air compressor and adjust the input power of the external air compressor in combination with the pressure feedback from the pressure gauge so that the water pressure on the rock sample scouring surface is the simulated water pressure, and carry out the rock scouring test.

[0020] S5. After the test, disconnect the power supply and the external air compressor, slowly open the pressurization hole to balance the pressure inside and outside the device, close the drain valve and the water inlet valve, open the rock sample holder, take out the simulated scour rock sample, and observe the deformation of its scour surface.

[0021] In a preferred embodiment, when multiple sets of unit tubes are set, in step S4, the flow velocity V of the scouring water on the rock sample scouring surface is... i Based on the continuity equation and the flow velocity V0 measured in the velocity measurement section, and the cross-sectional area A of the scouring point of each unit pipe, i The calculation is performed on the cross-section A0 of the speed measurement section, and the calculation equation is as follows:

[0022] Q=A0·V0=A i ·V i；

[0023] V i =V0·A0 / A i。

[0024] The present invention provides a slope rock erosion simulation device and method based on the principle of continuity, which has the following beneficial effects:

[0025] 1. This invention provides a slope rock erosion simulation device and method based on the principle of continuity, which makes laboratory rock erosion simulation experiments more convenient and provides more precise control and more intuitive observation feedback on factors affecting rock erosion results, such as water flow velocity and water depth.

[0026] 2. This invention, through the combination of different pipe segments and the continuity equation, can simultaneously conduct multiple sets of rock erosion simulation experiments under different flow velocity conditions, allowing for mutual comparison and improving experimental efficiency.

[0027] 3. The loop channel consisting of a water tank, a water pump section, a simulation experiment section, and a speed measurement section in this invention can realize the recycling of experimental water, which consumes less water than other rock erosion simulation devices.

[0028] 4. In this invention, the water flow section A at the scouring point... i Both the cross-sectional area A0 of the speed measurement section and the cross-sectional area A0 of the scour section are fixed values, and the cross-sectional area A0 of the scour section at the scour point is also fixed. i All of them are smaller than the cross-sectional area A0 of the velocity measurement section, which can increase the upper limit of the velocity measurement section and improve the device's ability to simulate the scouring of high-speed water flow.

[0029] 5. The flow velocity V of the scouring water on the rock sample scouring surface described in this invention i Based on the continuity equation combined with the feedback velocity V0 from the velocity measurement section and the cross-sectional area A at the scour point... i By measuring the cross-section A0 of the velocity measurement section, the flow velocity at the scour location can be obtained, allowing for the simultaneous simulation of rock scour under multiple flow velocity conditions. Attached Figure Description

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0031] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the water tank device.

[0033] Figure 3 This is a cross-sectional view of a unit tube;

[0034] Figure 4 This is a cross-sectional view of the rock sample holder;

[0035] Figure 5 This is a cross-sectional view of the scour test section of the present invention;

[0036] Figure 6 This is a cross-sectional view of the speed measuring section of the present invention;

[0037] Figure 7 This is a schematic diagram of the water pump supply device of the present invention.

[0038] In the figure: scour test section 100, unit pipe 110, rock sample loading interface 111, rock sample installation port 112, rock sample limiting plate 113, head end guide channel 114, scour simulation channel 115, and end flow dispersion channel 116;

[0039] Rock sample holder 200, fixing cylinder 210, compression spring 220, rock sample pressure plate 230;

[0040] Speed ​​measurement zone 300;

[0041] Flow measurement device 400, magnetic induction coil 410, electrode probe 420;

[0042] Water supply mechanism 500, water tank device 510, water tank 511, drain valve 512, inlet valve 513, water inlet 514, pressurization hole 515, pressure gauge 516, water pump supply device 520, water pump 521, water supply pipe 522, water outlet pipe 523. Detailed Implementation

[0043] Example 1:

[0044] like Figures 1-7 As shown, a slope rock erosion simulation device based on the principle of continuity includes an erosion test section 100, such as... Figure 5 As shown, the scour test section 100 includes several unit pipes 110, such as... Figure 3As shown, the unit tube 110 is provided with a rock sample loading interface 111 on one or both sides. The rock sample loading interface 111 is used to connect with the rock sample holder 200. The rock sample loading interface 111 is provided with a rock sample installation port 112 on the side near the inner wall of the unit tube 111. The rock sample installation port 112 is provided with a rock sample limiting piece 113 on the side near the inside of the unit tube 110. The rock sample limiting piece 113 limits the position of the rock specimen and does not cover the scouring test surface of the rock specimen.

[0045] The single-unit tube 110 can be selected for single-unit simulation or dual-unit simulation. When performing single-unit simulation, a rock sample is placed in the rock sample installation port 112 on one side of the unit tube 110, and the rock sample installation port 112 on the other side is blocked with a rock sample holder 200. When performing bipedal simulation, rock samples are installed in the rock sample installation ports 112 on both sides of the unit tube 110, and then the rock sample holder 200 is installed.

[0046] like Figure 4 As shown, the rock sample holder 200 includes a fixed cylinder 210 with one end closed, a compression spring 220 is provided inside the fixed cylinder 210, and a rock sample pressure plate 230 is provided at one end of the compression spring 220 to press against the outside of the rock sample. The fixed cylinder 210 is threadedly connected to the rock sample loading interface 111.

[0047] Downstream of the scour test section 100, there is a velocity measuring section 300, and the velocity measuring section 300 is equipped with a flow measuring device 400.

[0048] The adjacent unit pipes 110 are connected by threads, the unit pipe 110 at the tail end is connected to the speed measuring section 300, and the unit pipe 110 at the head end is connected to the water supply mechanism 500, which facilitates the installation of the flushing test section 100 and the increase or decrease of the number of unit pipes 110.

[0049] Preferred, such as Figure 3 As shown, the channels within the unit tube 110 include a head-end flow guiding channel 114, a scour simulation channel 115, and an end-end flow dispersing channel 116 connected in sequence, and the rock sample installation port 112 is connected to the scour simulation channel 115.

[0050] The diameters of the scouring simulation channels 115 of several of the aforementioned unit tubes 110 are different, such as... Figure 5 As shown, the water flow section A at the scouring point of each unit pipe 110 i The cross-sectional area A0 of the water flow is smaller than that of the velocity measurement section 300. This can increase the upper limit of the velocity measurement section 300 and improve the device's ability to simulate the scouring effect of high-speed water flow.

[0051] Because multiple sets of scour simulation channels 115 with different diameter unit pipes 110 are set up, multiple sets of rock scour simulation experiments under different flow velocity conditions can be carried out simultaneously and can be compared with each other, which improves the experimental efficiency.

[0052] It also includes a water supply mechanism 500, which supplies water to the scour test section 100 and the velocity measurement section 300 to form a circulating water path, which consumes less water than other rock scour simulation devices.

[0053] In this embodiment, adjacent unit tubes 110 are connected by threads, the unit tube 110 at the tail end is connected to the speed measuring section 300, and the unit tube 110 at the head end is connected to the water supply mechanism 500, which facilitates disassembly and replacement.

[0054] In this embodiment, as Figure 2 and Figure 7 As shown, the water supply mechanism 500 includes a water tank device 510 and a water pump supply device 520. The water tank device 510 includes a water tank 511, with a drain valve 512 at the outlet and an inlet valve 513 at the inlet. The water pump supply device 520 includes a water pump 521, with the inlet of the water pump 521 connected to the outlet of the water tank 511 via a water supply pipe 522. The outlet of the water pump 521 is connected to an outlet pipe 523, which is connected to the scouring test section 100. The speed measuring section 300 is connected to the inlet of the water tank 511.

[0055] The outlet pipe 523 is a bend to facilitate the accelerated water flow to be directed to the scouring test section 100.

[0056] Preferably, the water tank 511 is a closed water tank made of metal. The top of the water tank 511 is provided with a water inlet 514 and a pressure hole 515. The pressure hole 515 is used to connect to the pipeline of the air compressor. A pressure gauge 516 is provided on one side of the water tank 511. The pressure gauge 516 is flush with the center point of the rock sample scour surface of the scour test section 100.

[0057] By connecting the pressure port 515 to an air compressor, the relative pressure inside the device is changed. According to Pascal's principle, this pressure can be transmitted to various points inside the liquid. The pressure gauge 516 provides feedback on the pressure magnitude. The pressure gauge 516 can provide feedback on the relative pressure P at the center of the rock sample scouring surface at the same horizontal line, simulating the effect of water depth on the scouring of the rock sample.

[0058] Start the external air compressor and adjust its input power based on the pressure feedback from the pressure gauge to ensure that the water pressure on the rock sample scouring surface is the simulated water pressure.

[0059] like Figure 6 As shown, the flow measurement device 400 is an electromagnetic flow meter.

[0060] The system includes a magnetic induction coil 410 positioned outside the velocity measuring section 300, and an electrode probe 420 located inside the velocity measuring section 300. It measures the velocity of the liquid inside the pipe using the Faraday principle of electromagnetic induction. The magnetic induction coil 410, located on the upper and lower sides of the velocity measuring section 300, generates a vertical magnetic field inside the pipe when energized. The electrode probe 420 is located on the left and right sides of the pipe wall, slightly off-center from the center of the velocity measuring section 300, probing directly into the moving water flow. Since the water flow is a conductor, it generates a weak voltage signal when cutting magnetic field lines in the magnetic field, and the voltage is proportional to the flow velocity. The electrode probe 420 receives this electrical signal, which is then amplified and processed by analog-to-digital conversion circuits to provide real-time flow velocity feedback.

[0061] Example 2:

[0062] A test method for a bank slope rock erosion simulation device based on the principle of continuity includes the following steps:

[0063] S1. Select the number of unit tubes 110 in the scour test section 100 as needed. The unit tubes 110 are connected end to end to form the scour test section 100. If multiple sets of rock scour simulation experiments under different flow velocity conditions are to be carried out simultaneously and compared with each other, set up several sets of unit tubes 110 with different diameters.

[0064] Take a cubic rock sample and place it into the rock sample installation port 112 of each unit tube 110, so that the test surface of the rock sample is in close contact with the rock sample limiting plate 113. Install the rock sample holder 200 into the rock sample loading interface 111. Under the action of the compression spring 220, the test surface of the rock sample is pressed against one side of the rock sample limiting plate 113. Repeat the operation to load rock sample into each unit tube 110.

[0065] S2. Connect the inlet end of the flushing test section 100 to the outlet pipe 523, connect the outlet end of the flushing test section 100 to the speed measuring section 300, connect the tail end of the speed measuring section 300 to the inlet of the water tank 511, and connect the water supply pipe 522 of the water pump supply device 520 to the outlet of the water tank 511 to form a circulation loop.

[0066] S3. Open the water inlet 514 of the water tank 511 to add water to the water tank 511, so that the circulation loop is full of water, and then close the water inlet 514.

[0067] S4. Connect the external air compressor to the pressure port 515, start the water pump 521 to start the internal water circulation, adjust the power of the water pump 521 according to the flow velocity measured in the velocity measuring section 300 to meet the required simulated scouring flow velocity, start the external air compressor and adjust the input power of the external air compressor in combination with the pressure feedback from the pressure gauge 516 to make the water pressure on the rock sample scouring surface the simulated water pressure, and carry out the rock scouring test.

[0068] The velocity V of the scouring water flow on the rock sample scouring surfacei Based on the continuity equation and the flow velocity V0 measured in velocity measurement section 300, and the water flow section A at the scouring point of each unit pipe 110, i The calculation is performed on the cross-section A0 of the 300 km / h speed measurement section. The calculation equation is as follows:

[0069] Q=A0·V0=A i ·V i；

[0070] V i =V0·A0 / A i。

[0071] S5. After the test, disconnect the power supply and the external air compressor, slowly open the pressurization hole 515 to balance the pressure inside and outside the device, close the drain valve 512 and the water inlet valve 513, open the rock sample holder 200, take out the simulated scour rock sample, and observe the deformation of its scour surface.

[0072] This device only requires measuring the water flow velocity in the 300-meter velocity measurement section. Combined with the continuity equation, it can simultaneously conduct multiple sets of rock erosion simulation experiments under different flow velocity conditions, allowing for mutual comparison and improving experimental efficiency.

[0073] This invention makes laboratory rock erosion simulation experiments more convenient, and provides more precise control methods and more intuitive observation feedback for factors affecting rock erosion results, such as water flow velocity and water depth.

[0074] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The embodiments and features described in these embodiments can be arbitrarily combined without conflict. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A slope rock erosion simulation device based on the principle of continuity, characterized in that, The test section (100) includes several unit tubes (110). One or both sides of each unit tube (110) are provided with a rock sample loading interface (111). The rock sample loading interface (111) is used to connect with the rock sample holder (200). The side of the rock sample loading interface (111) near the inner wall of the unit tube (111) is provided with a rock sample installation port (112). The side of the rock sample installation port (112) near the inside of the unit tube (110) is provided with a rock sample limiting piece (113). The rock sample holder (200) includes a fixed cylinder (210) closed at one end, a compression spring (220) is provided inside the fixed cylinder (210), a rock sample pressure plate (230) is provided at one end of the compression spring (220) and pressed against the outside of the rock sample, and the fixed cylinder (210) is threadedly connected to the rock sample loading interface (111). Downstream of the scour test section (100) is a velocity measuring section (300), and a flow measuring device (400) is installed in the velocity measuring section (300). It also includes a water supply mechanism (500), which is used to supply water to the scouring test section (100) and the speed measuring section (300) to form a circulating water path.

2. The slope rock erosion simulation device based on the principle of continuity according to claim 1, characterized in that, The channels within the unit tube (110) include a first-end flow guide channel (114), a scour simulation channel (115), and an end flow dispersion channel (116) connected in sequence, with the rock sample installation port (112) connected to the scour simulation channel (115).

3. The slope rock erosion simulation device based on the principle of continuity according to claim 1, characterized in that, The adjacent unit tubes (110) are connected by threads, the unit tube (110) at the tail end is connected to the speed measuring section (300), and the unit tube (110) at the head end is connected to the water supply mechanism (500).

4. The slope rock erosion simulation device based on the principle of continuity according to claim 2, characterized in that, The diameters of the scouring simulation channels (115) of several of the aforementioned unit pipes (110) are different, and the water flow section A at the scouring point of each unit pipe (110) is different. i The cross-section A0 of the water passage is smaller than the speed measurement section (300).

5. The slope rock erosion simulation device based on the principle of continuity according to claim 1, characterized in that, The water supply mechanism (500) includes a water tank device (510) and a water pump supply device (520). The water tank device (510) includes a water tank (511), the outlet of the water tank (511) is provided with a drain valve (512), and the inlet of the water tank (511) is provided with an inlet valve (513). The water pump supply device (520) includes a water pump (521), the inlet of the water pump (521) is connected to the outlet of the water tank (511) through a water supply pipe (522), the outlet of the water pump (521) is connected to an outlet pipe (523), and the outlet pipe (523) is connected to the scouring test section (100). The speed measuring section (300) is connected to the inlet of the water tank (511).

6. A slope rock erosion simulation device based on the principle of continuity according to claim 5, characterized in that, The outlet pipe (523) is a bend.

7. A slope rock erosion simulation device based on the principle of continuity according to claim 5, characterized in that, The water tank (511) is a closed water tank. The top of the water tank (511) is provided with a water inlet (514) and a pressure hole (515). The pressure hole (515) is used to connect to the pipeline of the air compressor. A pressure gauge (516) is provided on one side of the water tank (511). The pressure gauge (516) is flush with the center point of the rock sample scour surface of the scour test section (100).

8. A slope rock erosion simulation device based on the principle of continuity according to claim 1, characterized in that, The flow measurement device (400) is an electromagnetic flow meter.

9. The test method for a slope rock erosion simulation device based on the principle of continuity, as described in any one of claims 1 to 8, is characterized in that, Includes the following steps: S1. Select the number of unit tubes (110) of the scour test section (100) as needed. The unit tubes (110) are connected end to end to form the scour test section (100). Take a cubic rock sample and put it into the rock sample installation port (112) of each unit tube (110), so that the test surface of the rock sample is in close contact with the rock sample limiting plate (113). Install the rock sample holder (200) in the rock sample loading interface (111). Under the action of the compression spring (220), the test surface of the rock sample is pressed against the rock sample limiting plate (113) on one side. Repeat the operation to load the rock sample into each unit tube (110). S2. Connect the inlet end of the scouring test section (100) to the outlet pipe (523), connect the outlet end of the scouring test section (100) to the speed measuring section (300), connect the tail end of the speed measuring section (300) to the inlet of the water tank (511), and connect the water supply pipe (522) of the water pump supply device (520) to the outlet of the water tank (511) to form a circulation loop. S3. Open the water inlet (514) of the water tank (511) to add water to the water tank (511) so that the circulation loop is full of water, and close the water inlet (514). S4. Connect the pressurization hole (515) to the external air compressor, start the water pump (521) to make the internal water start to circulate, adjust the power of the water pump (521) according to the flow rate measured by the velocity measuring section (300) to meet the required simulated scouring flow rate, start the external air compressor and adjust the input power of the external air compressor in combination with the pressure gauge (516) feedback pressure to make the water pressure on the rock sample scouring surface the simulated water pressure, and carry out the rock scouring test; S5. After the test, disconnect the power supply and the external air compressor, slowly open the pressurization hole (515) to balance the pressure inside and outside the device, close the drain valve (512) and the water inlet valve (513), open the rock sample holder (200), take out the simulated scour rock sample, and observe the deformation of its scour surface.

10. The method for simulating bank slope rock erosion based on the principle of continuity, as described in claim 9, is characterized in that... When multiple sets of unit tubes (110) are set, in step S4, the flow velocity V of the scouring water on the rock sample scouring surface is... i Based on the continuity equation and the flow velocity V0 measured by the velocity measuring section (300), the cross-sectional area A of the scouring point of each unit pipe (110) is... i The calculation is performed on the cross-section A0 of the speed measurement section (300), and the calculation equation is as follows: Q=A0·V0=A i ·V i； V i =V0·A0 / A i。

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