Soil column environment multi-scene simulation comprehensive test device and method

Abstract

The invention provides a soil column environment multi-scene simulation comprehensive test device and method, and belongs to the field of environmental geotechnical engineering. The device comprises a simulation box, a soil column unit, a wind erosion water level control unit, a temperature control system, a sunlight rainfall simulation system and a wind power simulation system. The simulation box is provided with an access door, a splash-proof rain cover, a ventilation grid, a permeable grid and a drainage pipe. The soil column unit is composed of a liquid collecting bottle, a base, a hollow cylinder set and a wind erosion water level control mechanism and can simulate different heat exchange working conditions. The wind erosion water level control unit drives the flexible waterproof cloth to ascend and descend through a motor, and wind erosion and water level control is achieved. The temperature control system adjusts the temperature in the box through the cold-heat exchange pipe. The sunlight and rainfall simulation system simulates rainfall and sunlight through a shower head and a sunlight irradiation lamp. The wind power simulation system generates stable airflow through the axial flow fan array. According to the invention, various environment scenes can be simulated at the same time, and the characteristic change of soil under different environment conditions can be accurately researched.

Description

Technical Field

[0001] This invention belongs to the field of environmental geotechnical engineering, specifically relating to a comprehensive test device and method for multi-scenario simulation of soil column environment. Background Technology

[0002] Soil column tests, as a core method for studying water transport, solute migration and ecological response in soil-vegetation systems, have wide applications in environmental geotechnical engineering, agricultural ecology and pollution remediation.

[0003] The parameters measured in soil column experiments include soil moisture content, infiltration rate, evaporation-transpiration, permeability coefficient, and vegetation transpiration efficiency. These parameters collectively reveal the interaction patterns of water, solutes, and energy in the soil-vegetation system. Wind field, a long-neglected environmental variable in soil column experiments, has a significant regulatory effect on these parameters. For example, wind speeds >3.1 m / s significantly accelerate soil evaporation (especially in the 0–20 cm surface layer), while >7 m / s inhibits vegetation transpiration (stomatal closure response). Strong winds (>5 m / s) drive salt accumulation in the topsoil (evaporation enhancement effect) and promote the diffusion of fine particles (<0.1 mm) adsorbed heavy metals in suspension. Studies have shown that ignoring the wind field will lead to a water balance calculation error >25%. When multiple environmental factors such as wind, sunlight, and rainfall interact, the resulting effect is far greater than the sum of single factors. For example, after wind erosion pretreatment of soil, the amount of subsequent rainfall erosion can increase by 30-50%. Under the combined effects of high temperature, strong sunlight, and medium wind speed, vegetation transpiration reaches its peak, while the transpiration efficiency in a windless environment at the same temperature decreases by 60%.

[0004] Current soil column environment simulation devices have the following limitations:

[0005] 1) Most devices can only perform single-factor or fixed multi-factor simulations and cannot achieve dynamic coupling;

[0006] 2) Lack of a uniform and stable wind field simulation system;

[0007] 3) It is impossible to integrate wind erosion simulation and water level control functions within the same device;

[0008] 4) Ignore the influence of lateral thermal boundary conditions on the experimental results. Summary of the Invention

[0009] To address the problems existing in the prior art, the present invention provides a comprehensive experimental device and method for multi-scenario simulation of soil column environment. The purpose is to simultaneously simulate multiple environmental scenarios, including wind, rain, temperature, etc., so as to more accurately study the changes in soil characteristics under different environmental conditions.

[0010] To achieve the above objectives, the specific solution of the present invention is as follows:

[0011] A multi-scenario simulation test device for soil column environment includes a simulation box, a soil column unit, a wind erosion and water level control unit, a temperature control system, a solar precipitation simulation system, and a wind simulation system;

[0012] The simulation box has a ventilation grid on at least one side of the top, a permeable grid on the inner side of the bottom, and a drainage pipe on the outer side of the bottom. Multiple soil column units are installed on the inner side of the bottom of the simulation box. Each soil column unit includes a liquid collection bottle and a base, a hollow cylinder group, and a wind erosion water level control mechanism connected from bottom to top. The liquid collection bottle is correspondingly set at the water outlet of the base. The hollow cylinder group includes multiple hollow cylinders, which are threaded together.

[0013] A wind erosion water level control unit is detachably installed on the top of each soil column unit. Each wind erosion water level control unit includes a circular base, a mesh, a flexible waterproof cloth, a traction ring, a transmission rod, a motor, a second connecting column, an upper support ring, and a first connecting column. A mesh is installed along the inner edge of the circular base. The upper part of the circular base is embedded in the flexible waterproof cloth, which is circular in shape with an inverted U-shaped cross-section. The lower part of the circular base is provided with a thread that fits the top of the hollow cylinder group, so that the circular base is threadedly connected to the top of the hollow cylinder group. The traction ring is sleeved and connected to the outside of the flexible waterproof cloth. Multiple transmission rods are circumferentially arrayed and installed at the bottom of the traction ring. The upper support ring is connected to multiple second connecting columns. Each second connecting column is equipped with a motor. The output shaft of each motor is connected to a transmission rod. Multiple first connecting columns are installed along the circumferential direction of the bottom of the upper support ring, and each of the multiple first connecting columns is connected to the circular base.

[0014] The temperature control system includes a heat exchange tube and a constant temperature circulation device. The two heat exchange tubes are installed on one side and the rear of the simulation box, respectively. One end of the two heat exchange tubes is connected, and the other end is connected to the inlet and outlet of the constant temperature circulation device through connecting pipes.

[0015] The solar rainfall simulation system includes a water supply pipe, a flow control valve, and a shower head and a solar lamp corresponding to the soil column unit. Each shower head is connected to one end of a branch pipe, and the other end of each branch pipe passes through the top of the simulation box and connects to the main water supply pipe. The main water supply pipe is connected to a water source. Each solar lamp is suspended on the top of the simulation box by a rod, and the solar lamp is located above the shower head.

[0016] The wind simulation system includes fan brackets and axial fans. At least two fan brackets are installed opposite each other on both sides inside the simulation box. Multiple axial fans are installed on each fan bracket to form an axial fan array. All the fans on one fan bracket are in the air supply direction, and all the fans on the opposite fan bracket are in the air intake direction.

[0017] Furthermore, the system includes a data acquisition and control system, which comprises a temperature and humidity sensor, a weight sensor, a wind speed sensor, a flow control valve, a flow sensor, a control box, and a computer. The temperature and humidity sensor is located on one side inside the simulation chamber. The weight sensor is located between the permeable grating and the soil column unit, with the liquid collection bottle placed on the weight sensor. Multiple wind speed sensors are mounted on wind speed sensor brackets, which are installed at the bottom inside the simulation chamber. The flow control valve is installed on the main water supply pipe. The flow sensor is connected to the main water supply pipe or a branch pipe and is connected in series with the flow control valve. The temperature and humidity sensor, weight sensor, wind speed sensor, flow control valve, flow sensor, wind erosion water level control unit, solar lamp, and motor are all connected to the control box, which is located on one side outside the simulation chamber and is connected to the computer.

[0018] Furthermore, the simulation box is provided with a rubber sheet on at least one side, each rubber sheet is provided with an array of cable holes that pass through the simulation box, and each rubber sheet is provided with a splash and rain cover on the upper outer side.

[0019] Furthermore, the simulation box has an inspection door on one side, and the top, bottom, sides and rear of the simulation box are made of heat-insulating material, while the front is made of heat-insulating transparent glass.

[0020] Furthermore, the base includes an inclined annular guide cover, support legs, and a funnel. Multiple support legs are installed at the bottom of the inclined annular guide cover. The inner ring wall of the inclined annular guide cover is provided with threads that are compatible with the hollow cylinder assembly. The funnel is installed at the bottom of the inner ring of the inclined annular guide cover, and the liquid collection bottle is correspondingly located below the funnel. A horizontal insertion tube communicating with the inner cavity of the hollow cylinder can be installed on the circumferential side wall of the hollow cylinder as needed. The hollow cylinder and the base are made of acrylic material or phenolic resin material.

[0021] Furthermore, the heat exchange pipe is a serpentine pipe, and the ventilation grid is square.

[0022] A test method for a multi-scenario simulation integrated test device for soil column environment includes the following steps:

[0023] Step 1: Fix the simulation box on a level surface and connect the external power supply and water source;

[0024] Step 2: Start the hot and cold constant temperature circulation device and axial flow fan array through the computer control box. Set the gradient wind speed through the computer. The wind speed is set to 0.5~8 m / s. Verify that the error between the wind speed sensor feedback value and the set value is within ±5%. Adjust the flow control valve to make the rainfall intensity within the range of 10~100 mm / h and observe the uniformity of the water output from the shower head. Set the hot and cold exchange pipe network to circulate in the range of 5~40℃ and confirm that the fluctuation of the temperature and humidity sensor monitoring value is ≤±0.5℃.

[0025] Step 3: Set the initial ambient temperature via computer. Once the environment inside the simulation chamber stabilizes, proceed to the next step.

[0026] Step 4: Determine the type and number of hollow cylinders according to experimental requirements and assemble the soil column unit. Install the wind erosion water level control unit on the top of the soil column unit. Fill each layer of hollow cylinder with experimental soil and plant vegetation on the surface of the experimental soil. Place the weight sensor above the permeable grid and place the assembled soil column unit on the weight sensor. Let it stand for 2-4 hours. The fluctuation of the weight sensor reading should be <0.1 g / min.

[0027] Step 5: Simulate specific scenarios such as strong wind drying, temperature stress, torrential rain erosion, and wind-rain coupling according to different experimental requirements:

[0028] Simulating a strong wind drying scenario: The computer control box turns on the axial flow fan array, sets the speed and air supply / suction direction of the axial flow fan array according to the test requirements, and forms different wind conditions. The wind speed is monitored in real time by the wind speed sensor to ensure that the wind speed is within the set range and the wind speed data is recorded; observe the soil erosion of the soil column unit under the action of wind force, and record the data of wind speed and wind erosion amount.

[0029] Simulated temperature stress scenario: The computer control box activates the constant temperature circulation device, which heats or cools the air inside the simulation chamber through the heat exchange pipe to bring the temperature inside the simulation chamber to the set target temperature; the temperature and humidity inside the simulation chamber are monitored in real time by temperature and humidity sensors to ensure that the temperature fluctuation is within the set range, and the temperature and humidity changes inside the simulation chamber are recorded periodically to ensure that the temperature is stable within the set range.

[0030] Simulated rainstorm erosion scenario: The computer-controlled control box turns on the water supply pipe and adjusts the water flow through the flow control valve, allowing water to flow into the shower head through the main water supply pipe and branch pipes. The shower head sprays water evenly onto the soil column unit to simulate the rainfall process. The flow control valve monitors and adjusts the rainfall intensity in real time to ensure that the rainfall intensity is within the set range. At the same time, the solar lights are turned on to simulate sunlight conditions, and data on rainfall intensity, sunlight intensity, and time are recorded.

[0031] Simulated wind and rain coupling scenario: The computer control box turns on the axial flow fan array and the solar rainfall simulation system respectively, controls the wind and rain intensity ratio, sets the wind and rain alternation or synchronization sequence, monitors the wind speed in real time through the wind speed sensor to ensure that the wind speed is within the set range, adjusts the rainfall intensity through the flow control valve to ensure that the rainfall intensity is within the set range, monitors the temperature and humidity in the simulation box in real time through the temperature and humidity sensors to ensure that the temperature fluctuation is within the set range, regulates the surface erosion resistance status through the wind erosion water level control unit, and records data on temperature, humidity, wind speed, rainfall intensity, solar radiation intensity, and soil erosion.

[0032] Step 6: End of experiment. Turn off the power and water supply, remove the soil column unit, and clean up the residual soil. Repeat steps 2 to 5 to study the changes in soil moisture content, infiltration rate, and evaporation-transpiration parameters of the soil column unit under different working conditions in the same environmental conditions.

[0033] Advantages of the present invention

[0034] 1. The multi-scenario simulation integrated test device and method for soil column environment of the present invention adopts a distributed wind simulation system, which generates uniform and stable airflow through a coordinated air supply and exhaust mode. This generates uniform and stable horizontal airflow within the chamber, effectively overcoming the problems of uneven flow field and excessive turbulence inherent in traditional single-point air supply methods. Furthermore, the internal air circulation method avoids temperature fluctuations within the chamber caused by air exchange with the outside environment while generating the required wind field, ensuring the independence and stability of the temperature field. Precise and continuous adjustment of wind speed within the range of 0.1~8 m / s is achieved, providing a reliable and repeatable wind field environment for wind erosion and wind-rain combined erosion experiments.

[0035] 2. This invention introduces a wind erosion water level control unit, which uses a motor to drive the flexible waterproof cloth to rise and fall, allowing for flexible switching between two functions on the same experimental platform: when lowered, it exposes the soil surface to accurately simulate the wind erosion process; when raised, it forms a controllable, sealed water accumulation space, supporting precise control of the water level from 0 to 150 mm. This dual-purpose design greatly expands the experimental capabilities and research value of the device. Furthermore, it integrates wind erosion simulation and water level control functions within the same experiment, and innovatively provides two optional soil column units: one with phenolic resin insulation and the other with acrylic non-insulating material. Users can easily switch between these options to meet different experimental needs and simulate drastically different lateral thermal boundary conditions. The wind erosion water level control unit, hollow cylinder assembly, and base within the soil column unit are connected by threads, allowing for flexible adjustment of the soil column height and the number of horizontal insertion tubes for sensor installation on the hollow cylinders at different heights. It also actively controls lateral thermal boundary conditions, accurately simulating natural conditions where heat exchange occurs only through the surface layer, or special conditions with significant lateral heat exchange, significantly improving the flexibility of experimental setup and the comprehensiveness of condition coverage. This invention addresses the technical challenges of traditional equipment, such as its inability to simulate temporal climate interactions, quantify wind field effects, and controllable lateral heat exchange, providing a novel platform for studying soil column tests under multi-field coupling effects.

[0036] 3. This invention breaks through the limitations of traditional equipment that can only simulate single factors or fixed multi-factors. For the first time, it realizes the dynamic temporal coupling and precise independent control of multiple environmental factors such as wind, rain, light, and temperature. It realizes the simulation of various complex environmental scenarios such as strong wind and dryness, rainstorm erosion, wind and rain intertwining, and temperature stress, and realistically simulates the interactive effects of multi-field coupling under natural conditions.

[0037] 4. The temperature control system, sunshine and rainfall simulation system, and wind simulation system of the present invention can operate independently or work in coordination. Through structural layout and heat insulation design, mutual interference is effectively avoided, ensuring the accuracy and reliability of the experiment, while significantly improving the adaptability and scalability of the device. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of the integrated test device for multi-scenario simulation of soil column environment according to the present invention.

[0039] Figure 2 , Figure 3 , Figure 4 All Figure 1 A schematic diagram of part of the internal structure of the device.

[0040] Figure 5 for Figure 1 Exploded view of the soil column unit and the wind erosion water level control unit.

[0041] Figure 6 for Figure 5 The diagram shows a hollow cylinder structure, where a is a hollow cylinder without a tube; b is a hollow cylinder with one tube; c is a hollow cylinder with two tubes; d is a hollow cylinder with three tubes; and e is a hollow cylinder with four tubes.

[0042] Figure 7 for Figure 5 A three-dimensional diagram of the hollow cylinder with four insertion tubes.

[0043] Figure 8 , 9 10 and 11 are all Figure 5 A schematic diagram of the wind erosion water level control unit.

[0044] Figure 12 for Figure 1 A schematic diagram of the structure of the wind speed sensor and the wind speed sensor bracket.

[0045] Figure 13 for Figure 1 Installation diagram of the splash guard and rubber sheet.

[0046] Figure 14 for Figure 1 A schematic diagram of a axial flow fan mounted on a fan bracket.

[0047] Figure 15 for Figure 1 A schematic diagram of the structure of the central base.

[0048] In the picture:

[0049] 1. Simulation box; 2. Soil column unit; 3. Hollow cylinder; 301. Horizontal insertion tube; 4. Base; 401. Inclined annular guide cover; 402. Support leg; 403. Funnel; 404. Thread; 5. Liquid collection bottle; 6. Wind erosion water level control unit; 601. Upper support ring; 602. Flexible waterproof cloth; 603. First connecting column; 604. Second connecting column; 605. Motor; 606. Transmission rod; 607. Circular base; 608. Grid; 609. Traction ring; 610. Thread; 7. Permeable grid 8. Fence; 9. Drainage pipe; 10. Main water supply pipe; 11. Flow control valve; 12. Shower head; 13. Sunlight; 14. Ventilation grid; 15. Splash and rain cover; 16. Control box; 17. Hot and cold constant temperature circulation device; 18. Computer; 19. Serpentine hot and cold exchange pipe; 20. Openable and closable maintenance door; 21. Branch pipe; 22. Hanger rod; 23. Fan bracket; 24. Axial flow fan; 25. Temperature and humidity sensor; 26. Weight sensor; 27. Rubber sheet; 28. Wind speed sensor bracket; 29. ​​Wind speed sensor. Detailed Implementation

[0050] The following explanation and description are provided in conjunction with the accompanying drawings and specific embodiments. It should be noted that these specific embodiments are not intended to limit the scope of the invention.

[0051] like Figures 1 to 15 As shown in the figure, this specific embodiment provides a comprehensive test device for multi-scenario simulation of soil column environment, including simulation box 1, soil column unit 2, wind erosion and water level control unit 6, temperature control system, sunlight and rainfall simulation system, wind simulation system, rubber sheet 26, splash and rain cover 14 and data acquisition and control system;

[0052] The top, bottom, sides, and rear of the simulation chamber 1 are made of heat-insulating material, while the front is made of heat-insulating transparent glass. A maintenance door is provided on one side of the simulation chamber 1 to facilitate the maintenance and replacement of parts inside the chamber, as well as the removal and placement of samples before, during, and after the experiment. At least one side of the top of the simulation chamber 1 is equipped with a ventilation grille 13 to form an airflow exchange channel between the inside and outside of the chamber. A permeable grating is laid on the inner side of the bottom of the simulation chamber 1, and a drain pipe 8 is provided on the outer side of the bottom of the simulation chamber 1 to promptly drain any accumulated water. In this embodiment, both the inner and outer sides of the simulation chamber 1 are equipped with rubber sheets 26. Each rubber sheet 26 has an array of cable holes that pass through the simulation chamber 1, and a splash-proof and rainproof cover 14 is provided on the upper outer side of each rubber sheet 26.

[0053] The cable hole array can generate radial compression deformation to adaptively wrap around the outer wall of the cable, forming a sealed cable passage. The splash and rain shield 14 is located above and outside the rubber sheet 26 to prevent rainwater from flowing into the simulation chamber 1 through the cable hole array. The rubber sheet 26 is made of a soft rubber material with good elasticity, and the splash and rain shield 14 is made of waterproof material and has a certain tilt angle to guide rainwater to the outside of the simulation chamber 1.

[0054] Multiple soil column units 2 are installed on the inner bottom of the simulation chamber 1 via weight sensors 25. Each soil column unit 2 includes a liquid collection bottle 5 and a base 4, a hollow cylinder assembly, and a wind erosion water level control mechanism connected sequentially from bottom to top by threads 610. The liquid collection bottle 5 is correspondingly positioned at the outlet of the base 4. Figure 6 and Figure 7 As shown, the hollow cylinder assembly includes multiple hollow cylinders 3. The number of hollow cylinders 3 is set according to the required height for the experiment to adjust the height of the hollow cylinder assembly. All hollow cylinders 3 are connected by threads 610. The base 4 includes an inclined annular guide cover 401, support legs 402, and a funnel 403. Multiple support legs 402 are installed at the bottom of the inclined annular guide cover 401. The inner ring wall of the inclined annular guide cover 401 has threads 404 adapted to the hollow cylinder assembly 3. The funnel 403 is installed at the bottom of the inner ring of the inclined annular guide cover 401. A liquid collection bottle 5 is correspondingly located below the funnel 403 to collect the liquid seeping out through the soil column unit. A horizontal insertion tube 301 communicating with the inner cavity of the hollow cylinder 3 can be installed on the circumferential side wall of the hollow cylinder 3 as needed. If the hollow cylinder 3 and the base 4 are made of non-insulating acrylic material, it is used to simulate a condition where there is significant lateral heat exchange between the soil and the surrounding environment. If the hollow cylinder 3 and the base 4 are made of phenolic resin heat insulation material, they are used to simulate the process by which soil mainly exchanges heat with air through the surface under natural working conditions.

[0055] To meet the sensor deployment requirements for different testing purposes, in this embodiment, the number of horizontal insertion tubes 301 in each hollow cylinder 3 is set to zero, one, two, three, or four, depending on the sensor deployment requirements. The sensors include, but are not limited to, moisture sensors, temperature sensors, pore pressure sensors, deformation sensors, and earth pressure sensors. Depending on the soil column height and monitoring requirements, hollow cylinders 3 of different specifications can be combined, as illustrated in the following examples:

[0056] Shallow soil column for monitoring moisture and temperature profiles: The soil column unit 2 is composed of two hollow cylinders 335 connected together, each with two horizontal insertion tubes 30136. From top to bottom, moisture sensors and temperature sensors are inserted into the horizontal insertion tubes 301 of the two hollow cylinders 3 to obtain high-resolution vertical parameter distributions.

[0057] Deep soil column, focusing on monitoring the stress and pore water pressure in the middle: The soil column unit 2 is composed of four hollow cylinders 3 connected together. The top hollow cylinder 3 has no horizontal insertion tube 301, the two middle hollow cylinders 3 have three horizontal insertion tubes 301 for deploying soil pressure sensors, pore pressure sensors and water pressure sensors, and the bottom hollow cylinder 3 has no horizontal insertion tube 301 to achieve targeted monitoring of key soil mechanical parameters.

[0058] Deformation and Multi-parameter Coupling Monitoring: The soil column unit 2 is constructed by alternating combinations of multiple hollow cylinders 3 with three horizontal insertion tubes 30136 and one horizontal insertion tube 30136. Deformation sensors are inserted and fixed into the hollow cylinders 3 with one horizontal insertion tube 301. Simultaneously, moisture, pore pressure, and earth pressure sensors are deployed at adjacent depths of the hollow cylinders 3 with three horizontal insertion tubes 301 to study the coupling relationship between soil deformation and water pressure, pore pressure, and earth pressure.

[0059] A wind erosion water level control unit 6 is detachably installed on top of each soil column unit 2. Figure 8 , 9 As shown in Figures 10 and 11, each wind erosion water level control unit 6 includes a circular base 607, a mesh 608, a flexible waterproof cloth 602, a traction ring 609, a transmission rod 606, a motor 605, a second connecting column 604, an upper support ring 601, and a first connecting column 603. A mesh 608 for fixing the surface soil is installed along the inner edge of the circular base 607 to prevent the edge soil from detaching from the soil column device during wind erosion environment simulation. The upper part of the circular base 607 is embedded in the flexible waterproof cloth 602, which is circular in shape with an inverted U-shaped cross-section. The lower part of the circular base 607 is provided with a hollow cylinder. The thread 610 at the top of the assembly connects the annular base 607 to the top hollow cylinder 3 of the hollow cylinder assembly. A traction ring 609 is fitted onto the outside of the flexible waterproof fabric 602. Four transmission rods 606 are arranged in a circumferential array at the bottom of the traction ring 609. The upper support ring 601 is connected to four second connecting posts 604, each with a motor 605 mounted on it. The output shaft of each motor 605 is connected to a transmission rod 606. Four first connecting posts 603 are installed along the circumferential direction at the bottom of the upper support ring 601, and each of the four first connecting posts 603 is connected to the annular base 607. The computer 17 sends commands to the control box 15 to drive the motor 605, controlling the transmission rods 606 to move up and down, thereby controlling the lifting and lowering of the flexible waterproof fabric 602. This allows the fabric to be pulled down to expose the top of the soil column for wind erosion simulation, and to be extended upwards to form an adjustable water accumulation area for rainfall simulation (0-150mm).

[0060] The temperature control system includes a serpentine heat exchange tube 18 and a constant temperature circulation device 16. The constant temperature circulation device 16 is a digital display heating and cooling equipment circulation device of model XU-GDW-5 / 30 from Xiniu Technology. The two heat exchange tubes are respectively installed on one side and the rear of the simulation chamber 1, and one end of the two heat exchange tubes is connected. The other end is connected to the inlet and outlet of the constant temperature circulation device 16 through connecting pipes. The function of the serpentine heat exchange tube 18 is to send instructions to the constant temperature circulation device 16 via the computer 17 to adjust the temperature of the serpentine heat exchange tube 18, so as to regulate the ambient temperature inside the simulation chamber 1.

[0061] The solar precipitation simulation system includes a water supply pipe, a flow control valve 10, and a shower head 11 and a solar lamp 12 correspondingly installed above the soil column unit 2. Each shower head 11 is connected to one end of a branch pipe 20, and the other end of each branch pipe 20 passes through the top of the simulation box 1 and connects to the main water supply pipe, which is connected to a water source. Each solar lamp 12 is suspended from the top of the simulation box 1 by a hanging rod 21, and the solar lamp 12 is located above the shower head 11 in the vertical direction, forming a non-contact, layered structure. The solar lamp 12 sends instructions to the control box 15 through the computer 17, and the control box 15 controls the on-state and illumination intensity of each solar lamp 12 to simulate the illumination angle and sunlight intensity.

[0062] The wind simulation system includes fan brackets 22 and axial fans 23. At least two fan brackets 22 are installed opposite each other on both sides of the simulation chamber 1. Each fan bracket 22 is equipped with multiple axial fans 23, forming an array of axial fans 23. The axial fans 23 on the two opposing fan brackets 23 are respectively set to the air supply direction and the air intake direction, that is, all the axial fans 23 on one fan bracket 22 are set to the air supply direction, and all the axial fans 23 on the opposite fan bracket 22 are set to the air intake direction. With this configuration, the axial fans 23 on the two opposing fan brackets 22 form a stable forced convection circulation airflow within the simulation chamber 1 to achieve efficient airflow and heat exchange. It also works in conjunction with a wind speed sensor 28 installed on a wind speed sensor bracket 27 to provide real-time wind speed feedback, and sends commands to the control box 15 via a computer 17 to adjust the wind speed, thus simulating ambient wind. In this embodiment, four fan brackets 22 are provided, which are respectively installed on the four sides inside the simulation box 1. Each fan bracket 22 is equipped with six axial flow fans 23, and the distance between adjacent fans is 10 cm to ensure uniform airflow distribution and efficient circulation.

[0063] The data acquisition and control system includes a temperature and humidity sensor 24, a weight sensor 25, a wind speed sensor 28, a flow control valve 10, a flow sensor, a control box 15, and a computer 17. The temperature and humidity sensor 24 is located on one side inside the simulation chamber 1. The weight sensor 25 is located between the permeable grating and the soil column unit 2, with the liquid collection bottle 5 placed on the weight sensor 25. Multiple wind speed sensors 28 are mounted on wind speed sensor brackets 27, which are installed at the bottom inside the simulation chamber 1. The flow control valve 10 is installed on the main water supply pipe 9, enabling the computer 17 and control box 15 to control the water flow rate in the water supply pipe, simulating different rainfall intensities. The flow sensor is installed on the main water supply pipe 9 or a branch pipe 20, ensuring that water flows through the flow sensor before entering the shower head. The flow sensor is connected to the control box, allowing it to monitor the water flow rate in real time and transmit the data to the control box. The control box calculates the rainfall intensity based on the flow sensor data and the spray area of ​​the shower head. The computer receives the rainfall intensity data through the control box and displays it in real time on the operating interface. Temperature and humidity sensor 24, weight sensor 25, wind speed sensor 28, flow control valve 10, flow sensor, wind erosion water level control unit 6, solar lamp 12 and motor 605 are respectively connected to control box 15. Control box 15 is located on one side outside simulation box 1. Control box 15 is connected to computer 17, so that computer 17 sends instructions to control box 15 to control the real-time acquisition and control of data such as temperature, wind speed, water level height at the top of soil column, soil erosion simulation and water flow velocity in the simulation box 1.

[0064] The temperature and humidity sensor is the commercially available Hongrun WS21 wall-mounted temperature and humidity transmitter.

[0065] The weight sensor 25 is the commercially available Jinno JHBM-H1 weight sensor.

[0066] The wind speed sensor 28 is a commercially available polycarbonate-RS485 wind speed sensor.

[0067] The flow control valve 10 is a commercially available Sanais W2W025-8 control valve.

[0068] The flow sensor is a commercially available LWGY turbine flow meter from E-Control Technology.

[0069] Temperature Control: The control box 15 receives instructions from the computer 17 to control the operation of the constant temperature circulation device 16. The constant temperature circulation device 16 adjusts the temperature of the liquid inside the serpentine heat exchange tube 18, thereby changing the temperature inside the simulation chamber 1. For example, when it is necessary to raise the temperature inside the simulation chamber 1, the control box 15 controls the constant temperature circulation device 16 to raise the temperature of the liquid inside the serpentine heat exchange tube 18. The heat is transferred to the air inside the simulation chamber 1 through the serpentine heat exchange tube 18, thereby raising the temperature inside the simulation chamber 1. Conversely, when it is necessary to lower the temperature, the control box 15 controls the constant temperature circulation device 16 to lower the temperature of the liquid inside the serpentine heat exchange tube 18, absorbing the heat inside the simulation chamber 1 to achieve a cooling effect.

[0070] Wind speed control: Control box 15 controls the speed and direction of the axial fan 23 according to the instructions of computer 17. By changing the speed of the axial fan 23, the wind speed can be adjusted; by changing the direction of the axial fan 23, the effects of air supply and suction can be achieved, thereby forming a stable forced convection circulation airflow within the simulation chamber 1. For example, when simulating a strong wind environment, control box 15 increases the speed of the axial fan 23 to increase the wind speed; when simulating a light wind environment, it decreases the speed of the axial fan 23 to decrease the wind speed. At the same time, by controlling the supply and suction directions of adjacent axial fans 23, the uniform distribution and efficient circulation of airflow within the simulation chamber 1 can be ensured.

[0071] Water level control at the top of the soil column: Control box 15 controls the operation of motor 605 in wind erosion water level control unit 6 according to instructions from computer 17. Motor 605 drives transmission rod 606 to move up and down, thereby controlling the raising and lowering of flexible waterproof cloth 602, thus changing the water level at the top of the soil column. For example, when it is necessary to lower the water level at the top of the soil column, control box 15 controls motor 605 to move transmission rod 606 downward, the flexible waterproof cloth 602 unfolds downward, and the water level at the top of the soil column decreases accordingly; when it is necessary to raise the water level at the top of the soil column, control box 15 controls motor 605 to move transmission rod 606 upward, the flexible waterproof cloth 602 retracts upward, and the water level at the top of the soil column increases accordingly. When the water level needs to be raised, water is replenished in conjunction with a rain-receiving device.

[0072] Soil column wind erosion simulation control: The computer 17 sends commands to the control box 15 to drive the motor 605 to move the transmission rod 606 up and down, thereby controlling the raising and lowering of the flexible waterproof cloth 602. This allows the soil column to be retracted downwards, exposing the top and simulating soil wind erosion. For example, when wind erosion simulation is needed, the control box 15 controls the motor 605 to move the transmission rod 606 downwards, causing the flexible waterproof cloth 602 to retract downwards, exposing the top of the soil column to the air. At this time, the wind generated by the axial fan 23 can erode the soil at the top of the soil column.

[0073] Water flow velocity control in the water supply pipe: The control box 15 controls the opening and closing degree of the flow control valve 10 according to the instructions of the computer 17. By adjusting the opening and closing degree of the flow control valve 10, the flow velocity of the water in the water supply pipe can be changed, thereby simulating different rainfall intensities.

[0074] For example, when it is necessary to simulate heavy rain, the control box 15 controls the flow control valve 10 to increase the opening degree, thereby increasing the water flow velocity in the water supply pipe and thus increasing the rainfall intensity; when it is necessary to simulate light rain, the control box 15 controls the flow control valve 10 to decrease the opening degree, thereby decreasing the water flow velocity in the water supply pipe and thus reducing the rainfall intensity.

[0075] Working principle:

[0076] 1. Equipment Start-up and Calibration: The computer 17 sends a command to the control box 15, which then starts the hot and cold constant temperature circulation device 16 and the axial flow fan array 23. A gradient wind speed is set, and the error between the feedback value and the set value of the wind speed sensor 28 is verified to be within ±5%. The flow control valve 10 is adjusted to maintain the rainfall intensity within the range of 10~100mm / h, and the uniformity of water output from the shower head 11 is observed. The hot and cold exchange pipe network is set to circulate within the range of 5~40℃, and the fluctuation of the monitoring value of the temperature and humidity sensor 24 is confirmed to be ≤±0.5℃.

[0077] 2. Initial Environment Setup: Set the initial ambient temperature inside the simulation chamber 1 using computer 17. Proceed to the next step after the environment stabilizes.

[0078] 3. Soil Column Unit 2 Assembly and Preparation: Determine the type and quantity of hollow cylinders 3 according to experimental requirements, and assemble soil column unit 2. Install the wind erosion water level control unit 6 on top of soil column unit 2, fill each layer of hollow cylinder 3 with experimental soil, and plant vegetation on the surface. Place the weight sensor 25 above the permeable grating, place the assembled soil column unit 2 on the weight sensor 25, and let it stand for 2-4 hours to ensure that the fluctuation of the weight sensor 25 reading is <0.1 g / min.

[0079] 4. Simulate different environmental scenarios:

[0080] Strong wind drying scenario: The computer 17 sends a command to the control box 15, which then turns on the axial flow fan array 23, sets the wind speed and direction, and monitors the wind speed in real time through the wind speed sensor 28, recording the wind speed and wind erosion data.

[0081] Temperature stress scenario: The computer 17 sends a command to the control box 15, which then activates the constant temperature and cooling circulation device 16 to adjust the temperature. The temperature and humidity are monitored in real time by the temperature and humidity sensor 24, and the temperature changes are recorded.

[0082] Heavy rain scenario: The computer 17 sends a command to the control box 15, which then turns on the water supply pipe and adjusts the rainfall intensity through the flow control valve 10, recording the rainfall intensity, sunshine intensity, and time data.

[0083] Wind and rain coupled scenario: The computer 17 sends a command to the control box 15, which simultaneously turns on the axial flow fan array 23 and the sunlight and rainfall simulation system, controls the wind and rain intensity ratio and timing, and monitors the wind speed and rainfall intensity in real time through the wind speed sensor 28 and the flow control valve 10, and records the relevant data.

[0084] 5. Data recording and analysis:

[0085] Real-time recording of data such as temperature, humidity, wind speed, rainfall intensity, solar radiation intensity, and soil erosion is performed. The data is then imported into computer 17 for processing, summarization, and analysis, generating data charts and summarizing the influence patterns of different environmental factors on soil column unit 2.

[0086] This device can efficiently and accurately simulate soil erosion processes under various environmental conditions, and achieves automated control and data acquisition through a data acquisition and control system, providing strong support for soil erosion research.

[0087] A test method for a multi-scenario simulation integrated test device for soil column environment includes the following steps:

[0088] Step 1: Equipment Installation and Inspection

[0089] Fixed simulation box 1: Place simulation box 1 on a level experimental site to ensure its stability.

[0090] Connect the power and water supply: Connect the external power supply to simulation box 1 to ensure all electrical equipment is functioning properly. Connect the water supply pipe to ensure the water supply system is operating normally.

[0091] Check the communication line: Check the communication line between the control box 15 and the computer 17 to ensure that the connection is normal and the data transmission is error-free.

[0092] Step 2: Equipment Calibration and Testing

[0093] Start-up equipment: The computer 17 controls the control box 15 to start the hot and cold constant temperature circulation device 16 and the axial flow fan array 23.

[0094] Set wind speed: Set the gradient wind speed via computer 17, with a wind speed range of 0.5~8 m / s. Use wind speed sensor 28 to monitor the wind speed in real time, ensuring that the error between the feedback value of wind speed sensor 28 and the set value is within ±5%.

[0095] Adjust rainfall intensity: Adjust the flow control valve 10 to keep the rainfall intensity within the range of 10~100mm / h. Observe the uniformity of water output from the shower head 11 to ensure that the water is sprayed evenly on the soil column unit 2.

[0096] Temperature and humidity settings: Set the heat exchange network to circulate within the range of 5~40℃. Use temperature and humidity sensors 24 to monitor the temperature and humidity inside the simulation chamber 1 in real time, ensuring that temperature and humidity fluctuations are within the set range of ≤±0.5℃.

[0097] Step 3: Initial Environment Setup

[0098] Set the initial ambient temperature: Set the initial ambient temperature inside simulation chamber 1 using computer 17. Wait for the environment inside simulation chamber 1 to stabilize, ensuring that the temperature and humidity reach the set values.

[0099] Step 4: Assembly and preparation of soil column unit 2

[0100] Assemble soil column unit 2: Determine the type and quantity of hollow cylinders 3 according to experimental requirements, and assemble soil column unit 2. Install the wind erosion water level control unit 6 on top of soil column unit 2. Fill each layer of hollow cylinder 3 with experimental soil, and plant vegetation on the surface of the experimental soil.

[0101] Install weight sensor 25: Place weight sensor 25 above the permeable slab. Place the assembled soil column unit 2 on weight sensor 25. Allow soil column unit 2 to stand: Allow soil column unit 2 to stand for 2-4 hours, ensuring that the reading fluctuation of weight sensor 25 is <0.1 g / min.

[0102] Step 5: Simulate different environmental scenarios

[0103] Simulating a strong wind drying scenario: Computer 17 controls control box 15 to activate the axial flow fan array 23. The rotational speed and airflow / intake directions of the axial flow fan array 23 are set according to experimental requirements to create different wind conditions. Wind speed is monitored in real-time by wind speed sensor 28, ensuring it remains within the set range of 0.5~8 m / s, and the wind speed data is recorded. The soil erosion of soil column unit 2 under wind action is observed, and wind speed and erosion amount data are recorded.

[0104] Simulated temperature stress scenario: Computer 17 controls control box 15 to activate the constant temperature circulation device 16, which heats or cools the air inside simulation chamber 1 through heat exchange pipes, bringing the temperature inside simulation chamber 1 to the set target temperature. Temperature and humidity sensors 24 monitor the temperature and humidity inside simulation chamber 1 in real time, ensuring temperature fluctuations are within the set range of 5~40℃ and humidity fluctuations are ≤±0.5℃. Temperature and humidity changes inside simulation chamber 1 are recorded periodically to ensure temperature stability within the set range.

[0105] Simulated rainstorm scenario: Computer 17 controls control box 15 to turn on the water supply pipe, and adjusts the water flow through flow control valve 10, allowing water to flow into shower head 11 through the main water supply pipe and branch pipe 20. Shower head 11 sprays water evenly onto soil column unit 2, simulating the rainfall process. The rainfall intensity is monitored and adjusted in real time through flow control valve 10 and flow sensor to ensure that the rainfall intensity is within the set range of 10~100 mm / h. At the same time, the solar lamp 12 is turned on to simulate solar conditions, and data on rainfall intensity, solar intensity, and time are recorded.

[0106] Simulating a wind-rain coupling scenario: Computer 17 controls control box 15 to activate the axial flow fan array 23 and the solar-rainfall simulation system, controlling the wind-rain intensity ratio and setting the alternation or synchronization sequence of wind and rain. Wind speed is monitored in real-time by wind speed sensor 28 to ensure it remains within the set range of 0.5~8 m / s. Rainfall intensity is adjusted by flow control valve 10 to ensure it remains within the set range of 10~100 mm / h. Temperature and humidity are monitored in real-time by temperature and humidity sensor 24 within simulation chamber 1 to ensure temperature fluctuations remain within the set range of 5~40℃. Surface erosion resistance is regulated by wind erosion water level control unit 6. Data on temperature, humidity, wind speed, rainfall intensity, solar radiation intensity, and soil erosion in step 5 are recorded in real-time.

[0107] Step 6: End of experiment. Turn off the power and water supply, remove soil column unit 2, and clean up the residual soil. Repeat steps 2 to 5 to study the changes in soil moisture content, infiltration rate, and evaporation-transpiration parameters of soil column unit 2 under different working conditions and the same environmental conditions.

Claims

1. A comprehensive experimental device for simulating multiple scenarios in a soil column environment, characterized in that, Includes a simulation box, soil column unit, wind erosion and water level control unit, temperature control system, solar precipitation simulation system and wind simulation system; The simulation box has a ventilation grid on at least one side of the top, a permeable grid on the inner side of the bottom, and a drainage pipe on the outer side of the bottom. Multiple soil column units are installed on the inner side of the bottom of the simulation box. Each soil column unit includes a liquid collection bottle and a base, a hollow cylinder group, and a wind erosion water level control mechanism connected from bottom to top. The liquid collection bottle is correspondingly set at the water outlet of the base. The hollow cylinder group includes multiple hollow cylinders, which are threaded together. A wind erosion water level control unit is detachably installed on the top of each soil column unit. Each wind erosion water level control unit includes a circular base, a mesh, a flexible waterproof cloth, a traction ring, a transmission rod, a motor, a second connecting column, an upper support ring, and a first connecting column. A mesh is installed along the inner edge of the circular base. The upper part of the circular base is embedded in the flexible waterproof cloth, which is circular in shape with an inverted U-shaped cross-section. The lower part of the circular base is provided with a thread that fits the top of the hollow cylinder group, so that the circular base is threadedly connected to the top of the hollow cylinder group. The traction ring is sleeved and connected to the outside of the flexible waterproof cloth. Multiple transmission rods are circumferentially arrayed and installed at the bottom of the traction ring. The upper support ring is connected to multiple second connecting columns. Each second connecting column is equipped with a motor. The output shaft of each motor is connected to a transmission rod. Multiple first connecting columns are installed along the circumferential direction of the bottom of the upper support ring, and each of the multiple first connecting columns is connected to the circular base. The temperature control system includes a heat exchange tube and a constant temperature circulation device. The two heat exchange tubes are installed on one side and the rear of the simulation box, respectively. One end of the two heat exchange tubes is connected, and the other end is connected to the inlet and outlet of the constant temperature circulation device through connecting pipes. The solar rainfall simulation system includes a water supply pipe, a flow control valve, and a shower head and a solar lamp corresponding to the soil column unit. Each shower head is connected to one end of a branch pipe, and the other end of each branch pipe passes through the top of the simulation box and connects to the main water supply pipe. The main water supply pipe is connected to a water source. Each solar lamp is suspended on the top of the simulation box by a rod, and the solar lamp is located above the shower head. The wind simulation system includes fan brackets and axial fans. At least two fan brackets are installed opposite each other on both sides inside the simulation box. Multiple axial fans are installed on each fan bracket to form an axial fan array. All the fans on one fan bracket are in the air supply direction, and all the fans on the opposite fan bracket are in the air intake direction.

2. The integrated test device for multi-scenario simulation of soil column environment according to claim 1, characterized in that, The system includes a data acquisition and control system, which comprises temperature and humidity sensors, weight sensors, wind speed sensors, flow control valves, flow sensors, a control box, and a computer. The temperature and humidity sensors are located on one side inside the simulation chamber. The weight sensors are located between the permeable grating and the soil column unit, with the liquid collection bottle placed on the weight sensors. Multiple wind speed sensors are mounted on wind speed sensor brackets, which are installed at the bottom inside the simulation chamber. The flow control valve is installed on the main water supply pipe. The flow sensor is connected to the main water supply pipe or a branch pipe and is connected in series with the flow control valve. The temperature and humidity sensors, weight sensors, wind speed sensors, flow control valves, flow sensors, wind erosion water level control unit, solar lamps, and motors are all connected to the control box, which is located on one side outside the simulation chamber and is connected to the computer.

3. The integrated test device for multi-scenario simulation of soil column environment according to claim 1, characterized in that, The simulation box is provided with a rubber sheet on at least one side, and each rubber sheet is provided with an array of cable holes that pass through the simulation box. Each rubber sheet is provided with a splash and rain cover on its outer upper side.

4. The integrated test device for multi-scenario simulation of soil column environment according to claim 1, characterized in that, The simulation chamber has an inspection door on one side. The top, bottom, sides and rear of the simulation chamber are made of heat-insulating material, and the front is made of heat-insulating transparent glass.

5. The integrated test device for multi-scenario simulation of soil column environment according to claim 1, characterized in that, The base includes an inclined annular guide cover, support legs, and a funnel. Multiple support legs are installed at the bottom of the inclined annular guide cover. The inner ring wall of the inclined annular guide cover is provided with threads that are compatible with the hollow cylinder assembly. The funnel is installed at the bottom of the inner ring of the inclined annular guide cover, and the liquid collection bottle is correspondingly located below the funnel. A horizontal insertion tube communicating with the inner cavity of the hollow cylinder can be installed on the circumferential side wall of the hollow cylinder as needed. The hollow cylinder and the base are made of acrylic material or phenolic resin material.

6. The integrated test device for multi-scenario simulation of soil column environment according to claim 1, characterized in that, The heat exchange pipe is a serpentine pipe, and the ventilation grid is square.

7. The test method of a multi-scenario simulation integrated test device for soil column environment according to any one of claims 1 to 6, characterized in that: Includes the following steps: Step 1: Fix the simulation box on a level surface and connect the external power supply and water source; Step 2: Start the hot and cold constant temperature circulation device and axial flow fan array through the computer control box. Set the gradient wind speed through the computer. The wind speed is set to 0.5~8 m / s. Verify that the error between the wind speed sensor feedback value and the set value is within ±5%. Adjust the flow control valve to make the rainfall intensity within the range of 10~100 mm / h and observe the uniformity of the water output from the shower head. Set the hot and cold exchange pipe network to circulate in the range of 5~40℃ and confirm that the fluctuation of the temperature and humidity sensor monitoring value is ≤±0.5℃. Step 3: Set the initial ambient temperature via computer. Once the environment inside the simulation chamber stabilizes, proceed to the next step. Step 4: Determine the type and number of hollow cylinders according to experimental requirements and assemble the soil column unit. Install the wind erosion water level control unit on the top of the soil column unit. Fill each layer of hollow cylinder with experimental soil and plant vegetation on the surface of the experimental soil. Place the weight sensor above the permeable grid and place the assembled soil column unit on the weight sensor. Let it stand for 2-4 hours. The fluctuation of the weight sensor reading should be <0.1 g / min. Step 5: Simulate specific scenarios such as strong wind drying, temperature stress, torrential rain erosion, and wind-rain coupling according to different experimental requirements: Simulating a strong wind drying scenario: The computer control box turns on the axial fan array, sets the speed and air supply / suction direction of the axial fan array according to the test requirements, and creates different wind conditions. The wind speed is monitored in real time by the wind speed sensor to ensure that the wind speed is within the set range, and the wind speed data is recorded. Observe the soil erosion of the soil column unit under the action of wind, and record the data of wind speed and wind erosion. Simulated temperature stress scenario: The computer control box activates the constant temperature circulation device, which heats or cools the air inside the simulation chamber through the heat exchange pipe to bring the temperature inside the simulation chamber to the set target temperature; the temperature and humidity inside the simulation chamber are monitored in real time by temperature and humidity sensors to ensure that the temperature fluctuation is within the set range, and the temperature and humidity changes inside the simulation chamber are recorded periodically to ensure that the temperature is stable within the set range. Simulated rainstorm erosion scenario: The computer-controlled control box turns on the water supply pipe and adjusts the water flow through the flow control valve, allowing water to flow into the shower head through the main water supply pipe and branch pipes. The shower head sprays water evenly onto the soil column unit to simulate the rainfall process. The flow control valve and flow sensor monitor and adjust the rainfall intensity in real time to ensure that the rainfall intensity is within the set range. At the same time, the solar lights are turned on to simulate sunlight conditions, and data on rainfall intensity, sunlight intensity, and time are recorded. Simulated wind and rain coupling scenario: The computer control box turns on the axial flow fan array and the solar rainfall simulation system respectively, controls the wind and rain intensity ratio, sets the wind and rain alternation or synchronization sequence, monitors the wind speed in real time through the wind speed sensor to ensure that the wind speed is within the set range, adjusts the rainfall intensity through the flow control valve to ensure that the rainfall intensity is within the set range, monitors the temperature and humidity in the simulation box in real time through the temperature and humidity sensors to ensure that the temperature fluctuation is within the set range, regulates the surface erosion resistance status through the wind erosion water level control unit, and records data on temperature, humidity, wind speed, rainfall intensity, solar radiation intensity, and soil erosion. Step 6: End of experiment. Turn off the power and water supply, remove the soil column unit, and clean up the residual soil. Repeat steps 2 to 5 to study the changes in soil moisture content, infiltration rate, and evaporation-transpiration parameters of the soil column unit under different working conditions in the same environmental conditions.

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