An experimental flume for simulating dynamic evolution of river-groundwater hydraulic connection

Abstract

An experimental sand tank for simulating dynamic evolution of river-groundwater hydraulic connection belongs to the technical field of groundwater simulation experiment devices and comprises a simulation sand tank, a river simulation box, a circulating water tank, a river water level control device, a groundwater water level control device, a water pressure monitoring probe, a pressure measuring drain, a data acquisition and processing device and a computer. The river water level and the groundwater water level on both sides of the aquifer are adjusted, and the monitoring data of the water pressure monitoring probe, the pressure measuring drain and the first to fourth flow water meters are combined, so that the process of dynamic evolution of river-groundwater hydraulic connection under various experimental conditions can be simulated, the law of dynamic evolution of river-groundwater hydraulic connection can be analyzed, and scientific reference basis can be provided for development and sustainable utilization of regional groundwater resources.

Description

Technical Field

[0001] The invention belongs to the technical field of groundwater simulation experimental devices, and in particular relates to an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection. Background Art

[0002] Rivers are a crucial component of the water cycle. The close hydraulic connection between rivers and groundwater is a ubiquitous phenomenon in nature. Understanding the dynamic evolution of this hydraulic connection can provide a scientific basis for the development and sustainable utilization of regional groundwater resources. This research is particularly valuable in arid and semi-arid regions where river seepage is the primary source of groundwater recharge. However, directly revealing the dynamic evolution of the river-groundwater hydraulic connection in the field requires extensive investigation and field work, consuming significant human and material resources. Therefore, conducting indoor simulation experiments on river-groundwater interactions and studying the dynamic evolution of this hydraulic connection during river recharge are of great significance. Summary of the Invention

[0003] The invention discloses an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection. The experimental sand trough can effectively simulate the dynamic evolution process of river-groundwater hydraulic connection during the process of river replenishing groundwater.

[0004] To achieve the above object, the technical solution of the present invention is:

[0005] An experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection, comprising a simulation sand trough, a river simulation box, a circulating water tank, a river water level control device, a groundwater level control device, a water pressure monitoring probe, a pressure measuring row, a data acquisition and processing device, and a computer. The simulation sand trough and the river simulation box are both cubic structures. Groundwater level control devices are provided at the left and right ends of the simulation sand trough. The river simulation box is embedded in the middle of the top of the simulation sand trough along the front-back direction. The rear end of the river simulation box is connected to the river water level control device. The river water level control device and the groundwater level control device are connected to the circulating water tank through a water pipe and a first flow monitoring device respectively. The river water level control device is connected to the river simulation box through a first connecting pipe. The groundwater level control device The control devices are connected to the simulated sand trough through pipelines. The front end of the river simulation box is provided with a water inlet pipe, and the water inlet pipe is connected to the circulating water tank through the second flow monitoring device. A water pump is provided on the water inlet pipe. The front and rear ends of the simulated sand trough are respectively evenly distributed with a number of data acquisition holes. The several data acquisition holes at the front and rear ends are arranged in a matrix, and the data acquisition holes at the front end are opposite to the acquisition holes at the rear end one by one. The data acquisition holes at the front end are all installed with water pressure monitoring probes, and the data acquisition holes at the rear side are respectively connected to the pressure measuring bar through soft water pipes. The water pressure monitoring probe, the pressure measuring bar, the first flow monitoring device, and the second flow monitoring device are respectively connected to the data acquisition and processing device through data lines. The data acquisition and processing device is electrically connected to the computer through the data line.

[0006] Preferably, the simulated sand trough is filled with fine sand and coarse sand and is used to simulate an aquifer, the bottom of the river simulation box is filled with fine sand and coarse sand and is used to simulate riverbed sediment, the bottom end and left and right side walls of the river simulation box are provided with first water leakage holes arranged in a matrix, the simulated sand trough and the river simulation box are both made of stainless steel, and a base is fixed to the bottom end of the simulated sand trough.

[0007] Preferably, the river water level control device includes a first head box and a first screw. The bottom end of the first screw is rotatably connected to the base, and the top end of the first screw passes through and is rotatably connected to a first fixed plate. One end of the first fixed plate is fixedly connected to the top of the rear end of the simulated sand tank. One end of the first head box is fixedly provided with a first connecting plate. The first screw passes through the first connecting plate and is screwed to the first connecting plate. The top end of the first screw is also provided with a first disc handle. The bottom end of the first head box is connected to the river simulation box through a first connecting pipe passing through the rear wall of the river simulation box. The bottom end of the first head box is connected to the circulating water tank through a first water pipe. The first flow monitoring device includes a first flow meter arranged on the first water pipe. A first guide rod is also longitudinally connected between the first fixed plate and the base. The first connecting plate is slidably connected to the first guide rod. The first head box rises and falls under the rotation of the first screw and realizes the adjustment of the water level in the river simulation box.

[0008] Preferably, the left and right ends of the simulated sand trough are respectively provided with a first water storage chamber and a second water storage chamber, and the first water storage chamber and the second water storage chamber are connected to the simulated sand trough through second water leakage holes arranged at the left and right ends of the simulated sand trough and arranged in a matrix, and the groundwater level control device includes a second water head box and a second screw arranged on the left side of the simulated sand trough; a third water head box and a third screw arranged on the right side of the simulated sand trough; the bottom end of the second screw is rotatably connected to the base, and the top end of the second screw passes through and is rotatably connected to a second fixed plate, one end of the second fixed plate is fixedly connected to the left end top of the first water storage chamber, and one end of the second water head box is fixedly provided with a second The connecting plate, the second screw rod passes through the second connecting plate and is screwed to the second connecting plate, the top of the second screw rod is also provided with a second disc handle, the bottom end of the second water head tank is connected to the first water storage chamber through a second connecting pipe passing through the bottom of the side wall of the first water storage chamber, the bottom end of the second water head tank is connected to the circulating water tank through a second water pipe, the first flow monitoring device includes a second flow water meter provided on the second water pipe, a second guide rod is further longitudinally connected between the second fixing plate and the base, the second connecting plate is slidably connected to the second guide rod, the second water head tank rises and falls under the rotation of the second screw rod and realizes the adjustment of the water level of the first water storage chamber;

[0009] The bottom end of the third screw is rotatably connected to the base, and the top end of the third screw passes through and is rotatably connected to a third fixed plate. One end of the third fixed plate is fixedly connected to the top of the right end of the second water storage chamber. One end of the third water head tank is fixedly provided with a third connecting plate. The third screw passes through the third connecting plate and is screwed to the third connecting plate. The top end of the third screw is also provided with a third disc handle. The bottom end of the third water head tank is connected to the second water storage chamber through a third connecting pipe passing through the bottom of the side wall of the second water storage chamber. The bottom end of the third water head tank is connected to the circulating water tank through a third water pipe. The first flow monitoring device includes a third flow water meter arranged on the third water pipe. A third guide rod is also longitudinally connected between the third fixed plate and the base. The third connecting plate is slidably connected to the third guide rod. The third water head tank rises and falls under the rotation of the third screw and realizes the adjustment of the water level of the second water storage chamber.

[0010] Preferably, the data acquisition holes on the front and rear end outer walls of the simulated sand trough below the river simulation box are densely arranged to form a monitoring probe density area, and the number of data acquisition holes in the monitoring probe density area is at least twice that of data acquisition holes of the same area in other areas.

[0011] Preferably, the second flow monitoring device is a fourth flow water meter, and the front and rear ends of the river simulation box are respectively connected to the third water storage chamber and the fourth water storage chamber, and the third water storage chamber and the fourth water storage chamber are respectively connected to the river simulation box through the third leakage holes arranged in a matrix at the front and rear ends of the river simulation box, and the first leakage hole, the second leakage hole and the third leakage hole are all provided with metal screens, the end of the water inlet pipe is connected to the bottom end of the third water storage chamber, and the fourth water storage chamber is connected to the first head tank through the first connecting pipe.

[0012] Preferably, the water pressure monitoring probe is used to measure the water pressure at different positions at the front end of the simulated sand tank, and the pressure measuring row measures the position potential energy and pressure potential energy at the location of each data acquisition hole through a number of pressure measuring tubes installed on the pressure measuring row. By comparing the monitoring data of the water pressure monitoring probes at the front and rear data acquisition holes and the monitoring data of the pressure measuring row, combined with the data from the first to fourth flow meters, the river-groundwater hydraulic connection law is analyzed.

[0013] A method for using an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection comprises the following steps:

[0014] (1) Preparation: prepare an experimental sand trough that simulates the dynamic evolution of river-groundwater hydraulic connection and ensure that all components are intact and usable;

[0015] (2) The first head tank, the second head tank, and the third head tank are all set at fixed heights, and water is slowly supplied to the circulating water tank. The water pump is turned on, and water is supplied from the third water storage chamber to the river simulation tank, and then the river simulation tank supplies water to the simulated sand tank to simulate the amount of water supplied by the river to the aquifer. When the data of the first to fourth flow meters are stable and the pressure measurement and water pressure data obtained by the computer remain stable, the water supply to the circulating water tank is stopped to simulate the water circulation flow in the experimental sand tank of the dynamic evolution of the hydraulic connection between the river and the groundwater;

[0016] (3) The height of the first water head box is adjusted by the first screw to conduct experiments under varying river depth conditions. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the river depth changes, using data from the water pressure monitoring probe, monitoring data from the pressure measuring row, and data from the first to fourth flow meters;

[0017] (4) Repeat steps (1) and (2), adjust the height of the second head tank or the third head tank, and conduct experiments to change the groundwater level on one side of the river. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater level on one side of the river changes through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row, and the data of the first to fourth flow meters;

[0018] (5) Repeat steps (1) and (2), and adjust the second head tank and the third head tank to the same height at the same time, so as to conduct an experiment under the condition of simultaneously changing the same groundwater level on both sides of the river. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to the same water level at the same time through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters;

[0019] (6) Repeat steps (1) and (2), and adjust the second head tank and the third head tank to different heights at the same time to conduct experiments under the conditions of changing the different water levels of groundwater on both sides of the river. The computer uses the data from the water pressure monitoring probe, the monitoring data from the pressure measuring row, and the data from the first to fourth flow meters to analyze the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to different water levels at the same time.

[0020] The beneficial effects of the experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection of the present invention are:

[0021] The present invention adjusts the river water level and the groundwater level on both sides of the aquifer, and combines the monitoring data of the water pressure monitoring probe, the pressure measuring row, and the first to fourth flow water meters to simulate the dynamic evolution process of the river-groundwater hydraulic connection under various experimental conditions, and analyzes the laws of the dynamic evolution of the river-groundwater hydraulic connection, thereby providing a scientific reference basis for the development and sustainable utilization of regional groundwater resources.

[0022] Figures in the specification

[0023] Figure 1 , a schematic structural diagram of the present invention;

[0024] 1—Simulated sand trough, 2—River simulation box, 3—First water storage chamber, 4—Second water storage chamber, 5—Second water head box, 6—Third water head box, 7—First water head box, 8—Second screw, 9—Third screw, 10—First screw, 11—Second connecting pipe, 12—Second water pipe, 13—Third connecting pipe, 14—Third water pipe, 15—First connecting pipe, 16—First water pipe, 17—Water inlet pipe, 18—Water pressure monitoring probe, 19—Data line, 20—Computer, 21—Second flow meter, 22—Third flow meter, 23—First flow meter, 24—Fourth flow meter, 25—Water pump, 26—Circulating water tank, 27—Monitoring probe encryption area, 28—Base, 29—Pressure measuring row, 30—Pressure measuring tube, 31—Soft water pipe, 32—Third fixing plate, 33—Third connecting plate 34—Third water storage chamber. DETAILED DESCRIPTION

[0025] The following description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0026] In the initial embodiment, the present invention is an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection, such as Figure 1As shown, it includes a simulated sand trough 1, a river simulation box 2, a circulating water tank 26, a river water level control device, a groundwater level control device, a water pressure monitoring probe, a pressure measuring row, a data acquisition and processing device, and a computer. The simulated sand trough 1 and the river simulation box 2 are both cubic structures. The left and right ends of the simulated sand trough 1 are provided with groundwater level control devices. The river simulation box 2 is embedded in the middle of the top of the simulated sand trough 1 along the front and back directions. The rear end of the river simulation box 2 is connected to the river water level control device. The river water level control device and the groundwater level control device are connected to the circulating water tank through a water pipe and a first flow monitoring device respectively. The river water level control device is connected to the river simulation box 2 through a first connecting pipe. The groundwater level control device is connected to the simulated sand trough 1 through a pipeline. A water inlet pipe 17 is provided at the front end of the flow simulation box 2, and the water inlet pipe 17 is connected to the circulating water tank 26 through a second flow monitoring device. A water pump 25 is provided on the water inlet pipe 17. A number of data acquisition holes are evenly distributed at the front and rear ends of the simulated sand tank 1. The data acquisition holes at the front and rear ends are arranged in a matrix, and the data acquisition holes at the front end are opposite to the acquisition holes at the rear end one by one. The data acquisition holes at the front end are all installed with water pressure monitoring probes 18, and the data acquisition holes at the rear side are respectively connected to the pressure measuring bar 29 through soft water pipes 31. The water pressure monitoring probe 18, the pressure measuring bar 29, the first flow monitoring device, and the second flow monitoring device are respectively connected to the data acquisition and processing device (not shown) through data lines. The data acquisition and processing device is electrically connected to the computer 20 through the data line 19.

[0027] In a further embodiment, Figure 1 As shown, the simulated sand trough 1 is filled with fine sand and coarse sand and is used to simulate an aquifer. The bottom of the river simulation box 2 is filled with fine sand and coarse sand and is used to simulate riverbed sediment. The bottom end and left and right side walls of the river simulation box 2 are provided with first water leakage holes arranged in a matrix (not shown in the figure). The simulated sand trough 1 and the river simulation box 2 are both made of stainless steel. The bottom end of the simulated sand trough 1 is fixed with a base 28.

[0028] In a further embodiment, Figure 1As shown, the river water level control device includes a first head box 7 and a first screw 10. The bottom end of the first screw 10 is rotatably connected to the base 28, and the top end of the first screw 10 passes through and is rotatably connected to a first fixed plate (not shown in the figure, refer to the relevant structure on the side of the third head box). One end of the first fixed plate is fixedly connected to the top of the rear end of the simulated sand tank 1, and one end of the first head box 7 is fixedly provided with a first connecting plate (not shown in the figure, refer to the relevant structure on the side of the third head box). The first screw 10 passes through the first connecting plate and is screwed to the first connecting plate. The bottom end of the first head box 7 is connected to the first connecting pipe 15 is connected to the river simulation box 2, the bottom end of the first water head box 7 is connected to the circulating water tank 26 through the first water pipe 16, the first flow monitoring device includes a first flow water meter 23 arranged on the first water pipe 16, and a first guide rod is longitudinally connected between the first fixed plate and the base (not drawn in the figure, refer to the relevant structure on the side of the third water head box), the first connecting plate is slidably connected to the first guide rod (to avoid the first water head box from rotating during the lifting and lowering process), the first water head box 7 is lifted and lowered under the rotation of the first screw 10 and the water level in the river simulation box 2 is adjusted, that is, it is used to simulate the adjustment of the water level of the river.

[0029] In a further embodiment, Figure 1 As shown, the left and right ends of the simulated sand trough 1 are respectively provided with a first water storage chamber 3 and a second water storage chamber 4, and the first water storage chamber 3 and the second water storage chamber 4 are connected to the simulated sand trough 1 through second water leakage holes (not shown in the figure) arranged at the left and right ends of the simulated sand trough 1 and arranged in a matrix. The groundwater level control device includes a second water head box 5 and a second screw 8 arranged on the left side of the simulated sand trough; a third water head box 6 and a third screw 9 arranged on the right side of the simulated sand trough 1; the bottom end of the second screw 8 is rotatably connected to the base 28, and the top end of the second screw 8 passes through and is rotatably connected to a second fixed plate, one end of the second fixed plate is fixedly connected to the top of the left end of the first water storage chamber 3, and one end of the second water head box 5 is fixed A second connecting plate is provided, the second screw 8 passes through the second connecting plate and is screwed to the second connecting plate, the bottom end of the second water head tank 5 is connected to the first water storage chamber 3 through a second connecting pipe 11 that passes through the bottom of the side wall of the first water storage chamber 3, the bottom end of the second water head tank 5 is connected to the circulating water tank 26 through a second water pipe 12, the first flow monitoring device includes a second flow water meter 21 provided on the second water pipe 12, and a second guide rod is further longitudinally connected between the second fixing plate and the base 28, the second connecting plate is slidably connected to the second guide rod, the second water head tank 5 rises and falls under the rotation of the second screw 8 and realizes the adjustment of the water level of the first water storage chamber 3, that is, the height of the groundwater level on the left side of the aquifer is adjusted;

[0030] The bottom end of the third screw 9 is rotatably connected to the base 28, and the top end of the third screw 9 passes through and rotatably connected to the third fixed plate 32. One end of the third fixed plate 32 is fixedly connected to the top of the right end of the second water storage chamber 4. One end of the third water head box 6 is fixedly provided with a third connecting plate 33. The third screw 9 passes through the third connecting plate 33 and is screwed to the third connecting plate 33. The bottom end of the third water head box 6 is connected to the second water storage chamber 4 through a third connecting pipe 13 passing through the bottom of the side wall of the second water storage chamber 4. The bottom end of the third water head box 6 is connected to the circulating water tank 26 through a third water pipe 14. The first flow monitoring device includes a third flow water meter 22 arranged on the third water pipe 14. A third guide rod (not marked in the figure) is also longitudinally connected between the third fixed plate 32 and the base 28. The third connecting plate 33 is slidably connected to the third guide rod. The third water head box 6 rises and falls under the rotation of the third screw 9 and realizes the adjustment of the water level of the second water storage chamber 4, and simulates the adjustment of the height of the groundwater level on the right side of the aquifer.

[0031] In a further embodiment, Figure 1 As shown, the data acquisition holes on the front and rear end outer walls of the simulated sand trough below the river simulation box 2 are densely arranged to form a monitoring probe encryption area 27. The number of data acquisition holes in the monitoring probe encryption area 27 is at least twice that of the data acquisition holes of the same area in other areas.

[0032] In a further embodiment, Figure 1 As shown, the second flow monitoring device is a fourth flow water meter 24, and the front and rear ends of the river simulation box 2 are respectively connected to the third water storage chamber 34 and the fourth water storage chamber (not marked in the figure), and the third water storage chamber and the fourth water storage chamber are respectively connected to the river simulation box through the third leakage holes arranged in a matrix at the front and rear ends of the river simulation box 2, and the first leakage hole, the second leakage hole, and the third leakage hole are all provided with a metal screen to prevent coarse sand or fine sand from passing through, and the end of the water inlet pipe 17 is connected to the bottom end of the third water storage chamber 34, and the fourth water storage chamber is connected to the first head tank 7 through the first connecting pipe 15.

[0033] In a further embodiment, Figure 1 As shown, the water pressure monitoring probe 18 is used to measure the water pressure at different positions at the front end of the simulated sand tank 1. The pressure measuring row 29 measures the position potential energy and pressure potential energy at the location of each data acquisition hole through a plurality of pressure measuring tubes 30 installed on the pressure measuring row 29. By comparing the monitoring data of the water pressure monitoring probe 18 at the front and rear data acquisition holes and the monitoring data of the pressure measuring row 29, combined with the data from the first to fourth flow meters, the hydraulic connection law between the river and the groundwater is analyzed.

[0034] In a further embodiment, Figure 1As shown, the present invention discloses a method for using an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection, comprising the following steps:

[0035] (1) Preparation: prepare an experimental sand trough that simulates the dynamic evolution of river-groundwater hydraulic connection and ensure that all components are intact and usable;

[0036] (2) The first head tank, the second head tank, and the third head tank are all set at fixed heights, and water is slowly supplied to the circulating water tank. The water pump is turned on, and water is supplied from the third water storage chamber 34 to the river simulation tank 2. Then, the river simulation tank 2 supplies water to the simulated sand tank 1 to simulate the amount of water supplied by the river to the aquifer. When the data of the first to fourth flow meters are stable and the pressure measurement data and water pressure data obtained by the computer remain stable, the water supply to the circulating water tank 26 is stopped to simulate the water circulation flow in the experimental sand tank of the dynamic evolution of the hydraulic connection between the river and the groundwater;

[0037] (3) The height of the first water head box 7 is adjusted by the first screw 10 to conduct experiments under varying river water depth conditions. The computer 20 analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the river water depth changes, using data from the water pressure monitoring probe 18, monitoring data from the pressure measuring row 29, and data from the first to fourth flow meters.

[0038] (4) Repeat steps (1) and (2) to adjust the height of the second water head tank 5 or the third water head tank 6 to change the groundwater level on one side of the river to conduct an experiment. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater level on one side of the river changes through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters;

[0039] (5) Repeat steps (1) and (2), and adjust the second water head tank 5 and the third water head tank 6 to the same height at the same time, so as to conduct an experiment under the condition of simultaneously changing the same groundwater level on both sides of the river. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to the same water level at the same time through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters;

[0040] (6) Repeat steps (1) and (2), and adjust the second head tank 5 and the third head tank 6 to different heights at the same time to conduct experiments under the conditions of changing the different water levels of groundwater on both sides of the river at the same time. The computer uses the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters to analyze the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to different water levels at the same time.

Claims

1. An experimental sand trough simulating the dynamic evolution of river-groundwater hydraulic connections, characterized by: The invention comprises a simulated sand trough, a river simulation box, a circulating water tank, a river water level control device, a groundwater level control device, a water pressure monitoring probe, a pressure measuring row, a data acquisition and processing device, and a computer. The simulated sand trough and the river simulation box are both cubic structures. The left and right ends of the simulated sand trough are provided with groundwater level control devices. The river simulation box is embedded in the middle of the top of the simulated sand trough along the front-back direction. The rear end of the river simulation box is connected to the river water level control device. The river water level control device and the groundwater level control device are connected to the circulating water tank through a water pipe and a first flow monitoring device respectively. The river water level control device is connected to the river simulation box through a first connecting pipe. The groundwater level control device is connected to the simulation box through a pipe respectively. The sand trough is connected, the front end of the river simulation box is provided with a water inlet pipe, the water inlet pipe is connected to the circulating water tank through the second flow monitoring device, and the water pump is provided on the water inlet pipe. The front and rear ends of the simulated sand trough are respectively evenly distributed with a number of data acquisition holes, the several data acquisition holes at the front and rear ends are arranged in a matrix, and the data acquisition holes at the front end are opposite to the acquisition holes at the rear end one by one. The data acquisition holes at the front end are all installed with water pressure monitoring probes, and the data acquisition holes at the rear side are respectively connected to the pressure measuring bar through soft water pipes. The water pressure monitoring probe, the pressure measuring bar, the first flow monitoring device, and the second flow monitoring device are respectively connected to the data acquisition and processing device through data lines for signal connection, and the data acquisition and processing device is electrically connected to the computer through the data line; The simulated sand trough is filled with fine sand and coarse sand and is used to simulate an aquifer. The bottom of the river simulation box is filled with fine sand and coarse sand and is used to simulate riverbed sediment. The bottom end and left and right side walls of the river simulation box are provided with first water leakage holes arranged in a matrix. The simulated sand trough and the river simulation box are both made of stainless steel. The bottom end of the simulated sand trough is fixed with a base. The river water level control device includes a first water head box and a first screw. The bottom end of the first screw is rotatably connected to the base, the top end of the first screw passes through and is rotatably connected to a first fixed plate, one end of the first fixed plate is fixedly connected to the top of the rear end of the simulated sand tank, one end of the first water head box is fixedly provided with a first connecting plate, the first screw passes through the first connecting plate and is screwed to the first connecting plate, the top end of the first screw is also provided with a first disc handle, the bottom end of the first water head box is connected to the river simulation box through a first connecting pipe passing through the rear wall of the river simulation box, the bottom end of the first water head box is connected to the circulating water tank through a first water pipe, the first flow monitoring device includes a first flow meter provided on the first water pipe, a first guide rod is also longitudinally connected between the first fixed plate and the base, the first connecting plate is slidably connected to the first guide rod, the first water head box rises and falls under the rotation of the first screw and realizes the adjustment of the water level in the river simulation box; The left and right ends of the simulated sand trough are respectively provided with a first water storage chamber and a second water storage chamber, and the first water storage chamber and the second water storage chamber are connected to the simulated sand trough through second water leakage holes arranged in a matrix at the left and right ends of the simulated sand trough. The groundwater level control device includes a second water head box and a second screw arranged on the left side of the simulated sand trough; a third water head box and a third screw arranged on the right side of the simulated sand trough; the bottom end of the second screw is rotatably connected to the base, and the top end of the second screw passes through and is rotatably connected to a second fixing plate, one end of the second fixing plate is fixedly connected to the left end top of the first water storage chamber, and one end of the second water head box is fixedly provided with a second connection Plate, the second screw passes through the second connecting plate and is screwed to the second connecting plate, the top of the second screw is also provided with a second disc handle, the bottom end of the second water head box is connected to the first water storage chamber through a second connecting pipe that passes through the bottom of the side wall of the first water storage chamber, the bottom end of the second water head box is connected to the circulating water tank through a second water pipe, the first flow monitoring device includes a second flow water meter provided on the second water pipe, a second guide rod is further connected longitudinally between the second fixing plate and the base, the second connecting plate is slidably connected to the second guide rod, the second water head box rises and falls under the rotation of the second screw and realizes the adjustment of the water level of the first water storage chamber; The bottom end of the third screw is rotatably connected to the base, and the top end of the third screw passes through and is rotatably connected to a third fixed plate. One end of the third fixed plate is fixedly connected to the top of the right end of the second water storage chamber. One end of the third water head tank is fixedly provided with a third connecting plate. The third screw passes through the third connecting plate and is screwed to the third connecting plate. The top end of the third screw is also provided with a third disc handle. The bottom end of the third water head tank is connected to the second water storage chamber through a third connecting pipe passing through the bottom of the side wall of the second water storage chamber. The bottom end of the third water head tank is connected to the circulating water tank through a third water pipe. The first flow monitoring device includes a third flow water meter arranged on the third water pipe. A third guide rod is also longitudinally connected between the third fixed plate and the base. The third connecting plate is slidably connected to the third guide rod. The third water head tank rises and falls under the rotation of the third screw and realizes the adjustment of the water level of the second water storage chamber.

2. The experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection according to claim 1, characterized in that: The data acquisition holes on the front and rear end outer walls of the simulated sand trough below the river simulation box are arranged in a dense manner to form a monitoring probe density area. The number of data acquisition holes in the monitoring probe density area is at least twice that of data acquisition holes of the same area in other areas.

3. The experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection according to claim 2, characterized in that: The second flow monitoring device is a fourth flow water meter. The front and rear ends of the river simulation box are respectively connected to the third water storage chamber and the fourth water storage chamber. The third water storage chamber and the fourth water storage chamber are respectively connected to the river simulation box through the third leakage holes arranged in a matrix at the front and rear ends of the river simulation box. The first leakage hole, the second leakage hole, and the third leakage hole are all provided with metal screens. The end of the water inlet pipe is connected to the bottom end of the third water storage chamber, and the fourth water storage chamber is connected to the first head tank through the first connecting pipe.

4. The experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection according to claim 3, characterized in that: The water pressure monitoring probe is used to measure the water pressure at different positions at the front end of the simulated sand tank. The pressure measuring row measures the position potential energy and pressure potential energy at the location of each data acquisition hole through a number of pressure measuring tubes installed on the pressure measuring row. By comparing the monitoring data of the water pressure monitoring probes at the front and rear data acquisition holes and the monitoring data of the pressure measuring row, combined with the data from the first to fourth flow meters, the hydraulic connection law between the river and groundwater is analyzed.

5. A method for using an experimental sand trough for simulating the dynamic evolution of river-groundwater hydraulic connection according to claim 4, comprising the following steps: (1) Preparation: prepare an experimental sand trough that simulates the dynamic evolution of river-groundwater hydraulic connection and ensure that all components are intact and usable; (2) The first head tank, the second head tank, and the third head tank are all set at fixed heights. Water is slowly supplied to the circulating water tank. The water pump is turned on to supply water from the third water storage chamber to the river simulation tank. Then, the river simulation tank supplies water to the simulated sand tank to simulate the amount of water supplied by the river to the aquifer. When the data of the first to fourth flow meters are stable and the pressure measurement and water pressure data obtained by the computer remain stable, the water supply to the circulating water tank is stopped to simulate the water circulation flow in the experimental sand tank of the dynamic evolution of the hydraulic connection between the river and the groundwater; (3) The height of the first water head box is adjusted by the first screw to conduct experiments under the condition of changing the river water depth. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the river water depth changes through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters; (4) Repeat steps (1) and (2) to adjust the height of the second head tank or the third head tank to change the groundwater level on one side of the river to conduct experiments. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater level on one side of the river changes through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters; (5) Repeat steps (1) and (2), and adjust the second head tank and the third head tank to the same height at the same time, so as to conduct an experiment under the condition of changing the same groundwater level on both sides of the river at the same time. The computer analyzes the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to the same water level at the same time through the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters; (6) Repeat steps (1) and (2), and adjust the second head tank and the third head tank to different heights at the same time to conduct experiments under the conditions of changing the different water levels of groundwater on both sides of the river. The computer uses the data of the water pressure monitoring probe, the monitoring data of the pressure measuring row and the data of the first to fourth flow meters to analyze the dynamic evolution characteristics and laws of the river-groundwater hydraulic connection when the groundwater on both sides of the river changes to different water levels at the same time.

Images