A test device for simulating submerged evaporation and a visual test method

Abstract

The present invention discloses a test device and a visualization test method for simulating submerged evaporation, which overcome the existing problems of difficulty in visualizing the submerged evaporation test process and cumbersome submerged evaporation measurement. The visualization test method comprises the following steps: 1) test preparation; 2) equipment installation; 3) test instrument parameter setting; 4) start of test; 5) data acquisition: (1) acquisition of water, salt and temperature sensor data; (2) acquisition of air humidity sensor data; (3) acquisition of CCD microscope image data; (4) acquisition of total test time data: when the test is completed, the start time and end time are recorded by a data acquisition system 16, and the total test time t is manually calculated; (5) acquisition of soil sample column mass data; (6) acquisition of fluorescent scale data: after the test, the fluorescent scale 36 on the water replenishment soil column tube 5 is manually observed to record the scale H2 at the top surface of the large cylinder of the lifting base 7; 6) submerged evaporation calculation.

Description

Technical Field

[0001] The invention relates to a test device and a test method using the device in the fields of geotechnical engineering geotechnical test technology, environmental science and engineering, and in particular to a test device and a visual test method for simulating submerged evaporation. Background Art

[0002] The area of ​​saline-alkali land in my country accounts for about 1 / 10 of my country's land area. The high salt content in saline-alkali soil has an adverse effect on vegetation, crop growth and construction projects. The main cause of soil salinization is that the soluble salt in shallow groundwater migrates to the surface under the action of soil capillary force, and the surface water evaporates and salt accumulates. Therefore, the study of groundwater evaporation is of great significance for the prevention and control of soil salinization. During groundwater evaporation, changes in surface temperature can cause soil moisture migration and change the properties of the soil. The change law of moisture field over time during soil evaporation provides important support for the study of groundwater evaporation.

[0003] At present, domestic indoor test devices for submersible evaporation generally place the soil column directly under natural conditions for testing. When the soil sample column is subjected to a submersible evaporation test under natural light, the moisture field changes of the soil sample column cannot be clearly observed from the outside of the soil column, so the height of moisture migration during the test cannot be determined. In addition, the test device for measuring submersible evaporation is cumbersome to operate. Many indoor test devices for submersible evaporation can only manually read data at various time points during the evaporation process or collect soil samples to measure evaporation through the drying method, which brings a lot of inconvenience to users. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the problems of difficulty in visualizing the diving evaporation test process and cumbersome measurement of diving evaporation in the prior art, and to provide a test device for simulating diving evaporation and a visualization test method.

[0005] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions: the steps of the visualization test method of the test device simulating diving evaporation are as follows:

[0006] 1) Test preparation:

[0007] (1) Preliminary test;

[0008] (2) Collection and processing of groundwater level fluctuation monitoring data;

[0009] (3) preparing soil sample columns;

[0010] (4) Calculate static water level:

[0011] According to the field monitoring data, the variation range of the groundwater level depth can be known. In the experiment, the water level with the smallest groundwater level fluctuation during the monitoring period is taken as the static water level H. j , calculate the static water level h of the test soil sample column according to the proportional coefficient e j ,h j =H j ×e;

[0012] 2) Equipment installation;

[0013] 3) Test instrument parameter settings:

[0014] (1) Setting up the groundwater level fluctuation model;

[0015] (2) Sensor data collection interval setting;

[0016] (3) Temperature controller settings;

[0017] (4) Air volume controller settings;

[0018] (5) Setting the shooting interval of CCD microscope camera;

[0019] 4) Start the experiment;

[0020] 5) Data collection:

[0021] (1) Collect moisture, salt and temperature sensor data;

[0022] (2) Collecting air humidity sensor data;

[0023] (3) Collecting CCD microscope camera image data;

[0024] (4) Collecting data on the total test time;

[0025] (5) Collect soil sample column quality data;

[0026] (6) Collecting fluorescence scale data;

[0027] 6) Calculation of diving evaporation.

[0028] The preliminary test described in the technical solution refers to:

[0029] (1) The PLC synchronous lifting system controls the CNC hydraulic jack to slowly rise, push the fluorescent solution into the first soil layer at the bottom of the soil sample column, stop lifting, and observe and record the height h1 of the fluorescent solution in the soil sample column;

[0030] (2) Control the CNC hydraulic jack through the PLC synchronous lifting system to inject the fluorescein solution to 20 mm, stop lifting, and observe and record the height h2 of the fluorescein in the soil sample column;

[0031] (3) Calculate the proportional coefficient μ1 of the first soil layer, μ1 = 20 / (h2-h1);

[0032] (4) If the soil sample column has multiple different soil layers, the proportional coefficient μ i =20 / (h i-2 -h i-1 ), after recording the h of the first soil layer 1-2 After that, the PLC synchronous lifting system (22) is used to control the numerical control hydraulic jack (15) to slowly rise, and the fluorescent solution is pushed into the second soil layer at the bottom of the soil sample column. The lifting is stopped, and the height h of the fluorescent substance in the soil sample column is observed and recorded. 2-1 , and then inject to 20mm, stop lifting, observe and record the height of the fluorescent substance in the soil sample column h 2-2 , calculate the proportional coefficient μ2 of the second soil layer, μ2=20 / (h 2-2 -h 2-1 ); the third soil layer μ3=20 / (h 3-2 -h 3-1 ) until the last layer of soil.

[0033] The collection and processing of groundwater level fluctuation monitoring data described in the technical solution refers to:

[0034] Monitoring wells are used to monitor the dynamics of groundwater levels in the field over a period of time. Groundwater level fluctuation monitoring data are collected through groundwater level monitoring instruments. The data include monitoring time and groundwater level height. The data can also be published in existing literature. The obtained monitoring data needs to be processed as follows:

[0035] (1) The groundwater level fluctuation monitoring data is made into an EXCEL table - groundwater level fluctuation monitoring data table. In the table header, column A is the monitoring time in minutes, column B is the groundwater level height in millimeters, and column C is the soil quality of the soil layer where the groundwater level is located, including sub-sand layer, sub-clay layer, medium-fine sand layer and coarse sand gravel layer. Rows 1, 2, 3...n in the table are the actual monitoring data values;

[0036] (2) Record the overall height of the field monitoring soil layer h, and scale it to the size of the water replenishment soil column. The height of the soil sample column in the water replenishment soil column is recorded as h b , calculate the proportionality coefficient e, e = h b / h;

[0037] (3) In the groundwater level fluctuation monitoring data table, add column D for the control data of the PLC synchronous jacking system and enter the formula in column D of the table: The unit is mm / min. A positive result is used to control the PLC synchronous lifting system to rise, and a negative result is used to control the PLC synchronous lifting system to descend.

[0038] The equipment installation described in the technical proposal refers to:

[0039] 1) The CNC hydraulic jack is placed at the center of the lower bottom plate. The bottom of the water replenishment soil column is mounted on the lifting base. Four screws are used to fix the cylinder fixing platform and the lower bottom plate. The thickness H3 of the small cylinder of the lifting base is measured with a ruler. A layer of vaseline is evenly applied inside the wall of the water replenishment soil column and above the partition to block moisture.

[0040] 2) Pour the replenishing solution mixed with fluorescein into the replenishing soil column, add the liquid level to the position of the partition, and then place the permeable stone on the partition. At this time, manually observe the fluorescent scale on the replenishing soil column and record the scale H1 at the top surface of the large cylinder of the lifting base;

[0041] 3) Place the prepared soil sample column into the water replenishment soil column tube, with the bottom of the soil sample column in contact with the permeable stone;

[0042] 4) Insert the four water, salt and temperature sensors into the soil sample through the No. 2 to No. 5 through holes in the water replenishment soil column, and insert the No. 2 air humidity sensor into the No. 1 through hole on the water replenishment soil column;

[0043] 5) Place UV lamp No. 1 and UV lamp No. 2 at the two corners on the right side of the lower base plate, and then install the main box on the lower base plate;

[0044] 6) The evaporative temperature-controlled heating lamp is placed inside the water-replenishing soil column, the lamp connecting column is inserted into the strip-shaped opening on the water-replenishing soil column, and the fixing clip at the tail of the lamp connecting column clamps the heating lamp fixing plate;

[0045] 7) Insert the No. 1 air humidity sensor into the sensor holder;

[0046] 8) Install the top plate onto the top of the main box; then insert the bottom of the evaporative speed-controlled exhaust fan into the conical opening in the center of the top plate;

[0047] 9) The CCD microscope camera is placed on the right side of the shooting port on the right wall of the main box.

[0048] The test instrument parameter settings described in the technical solution refer to:

[0049] 1) Groundwater level fluctuation model setting

[0050] Import the results of column D in the groundwater level fluctuation monitoring data table into the computer and transmit them to the PLC synchronous jacking system ( The unit is mm / min), which converts the digital signal into an electrical signal, and controls the dynamic change of the water level of the PLC synchronous lifting system through the change of the current signal. The PLC synchronous lifting system can control the height of the CNC hydraulic jack to rise and fall at 15 per minute, thereby simulating the actual change of the groundwater level in the field over time;

[0051] 2) Sensor data collection interval setting

[0052] (1) Power on the data acquisition system:

[0053] (2) The data acquisition system inputs the sampling interval through the timer in the computer. The interval can be set arbitrarily, and the shortest interval is 1 minute. The interval setting is determined according to the total test time. When the test time is a few hours or days, the collection interval is 1 minute to 20 minutes. When the test time is a few weeks or months, the collection interval is 60 minutes to 120 minutes.

[0054] 3) Temperature controller settings

[0055] The specific settings are completed through the following steps:

[0056] (1) The temperature controller is powered on;

[0057] (2) Press the mode switch button to change the mode to temperature mode;

[0058] (3) Press the increase button and decrease button of the start operation to adjust the required heating temperature of the temperature-controlled heating lamp. The temperature control range of the temperature controller is 5°C to 99°C. The setting of the heating temperature can refer to the average surface temperature of the land in each season;

[0059] (4) Press the mode switch button to change the mode to time mode;

[0060] (5) Press the increase button and decrease button of the start operation to adjust the power-on time of the temperature-controlled heating lamp to the required time;

[0061] (6) If you need to set a power-on and power-off cycle, after the power-on time is set, press the increase button and the decrease button of the stop operation to adjust the power-off time of the temperature-controlled heating lamp. The control time range of the temperature controller is 1 minute to 99 minutes. The power-on and power-off time can refer to the actual daily solar exposure time, such as a 4-hour power-on and power-off cycle or an 8-hour power-on and 16-hour power-off cycle; you can also choose a power-on time of 30 minutes to 480 minutes and a power-off time of 60 minutes to 960 minutes according to the test design;

[0062] 4) Air volume controller settings

[0063] The specific settings are completed through the following steps:

[0064] (1) Power on the air volume controller:

[0065] (2) Turn the knob clockwise to the desired air volume. The position of the indicator light indicates the current air volume. The air volume control range of the air volume controller is 0m 3 / h~280m 3 / h, the wind volume can be set by referring to the meteorological data of surface wind speed in each season;

[0066] 5) CCD microscope camera shooting interval setting

[0067] (1) Power on the CCD microscope camera:

[0068] (2) The CCD microscope camera inputs the sampling interval through the timer in the computer. The interval can be set arbitrarily, and the shortest interval is 1 minute. The interval setting is determined according to the total test time. When the test time is a few hours or days, the collection interval is 1 minute to 20 minutes. When the test time is a few weeks or months, the collection interval is 60 minutes to 120 minutes.

[0069] The data collection described in the technical solution refers to:

[0070] 1) Collect moisture, salt and temperature sensor data

[0071] (1) The moisture, salt and temperature sensors record the change data and curves of the moisture content, conductivity and temperature at different heights of the test soil sample column over time. In the curve, the x-axis is time and the y-axis is moisture content, conductivity and temperature;

[0072] (2) The moisture, salt and temperature sensors collect data through the AD chip in the data acquisition system. The AD chip uses a sampling pulse sequence to extract a series of discrete sample values ​​from the analog signals of water content, conductivity and temperature and converts them into digital signals. The moisture, salt and temperature sensors transmit the data to the computer through the data acquisition system.

[0073] 2) Collect air humidity sensor data

[0074] (1) Air humidity sensor No. 2 and air humidity sensor No. 1 respectively record the change data and change curve of the evaporation humidity of the soil sample column and the reference humidity outside the main box over time. In the curve, the x-axis is time and the y-axis is humidity;

[0075] (2) Air humidity sensor No. 2 and air humidity sensor No. 1 collect data through the AD chip in the data acquisition system. The AD chip uses a sampling pulse sequence to extract a series of discrete sample values ​​from the analog signal of humidity and converts them into digital signals. Air humidity sensor No. 2 and air humidity sensor No. 1 transmit data to the computer through the data acquisition system;

[0076] 3) Collect CCD microscope image data

[0077] During the test, the CNC hydraulic jack will push the replenishment solution mixed with fluorescein in the replenishment soil column into the soil sample column. Under the irradiation of the ultraviolet lamp, the fluorescein solution will show a bright fluorescent green. The position with fluorescent green is the water migration height of the soil sample column in the upper half of the replenishment soil column and the solution height in the lower half of the replenishment soil column. The specific collection steps are as follows:

[0078] (1) The CCD microscope camera takes real-time images of the right wall of the water replenishment soil column;

[0079] (2) The CCD microscope camera collects image information through the CCD image sensor in the body. The CCD microscope camera first converts the light signal into an electrical signal, and then converts the electrical signal into a digital signal through the analog-to-digital converter in the body. After the digital signal is formed, the microprocessor compresses the signal and converts it into an image file and stores it in the computer;

[0080] (3) The test operator can manually read the scale of the fluorescent scale on the water replenishment soil column at each time through the image stored in the computer to obtain the water migration height and solution replenishment height in the soil sample column;

[0081] 4) Collect total test time data

[0082] When the test is completed, the start and end time are recorded by the data acquisition system, and the total test time t is calculated manually;

[0083] 5) Collect soil sample column quality data

[0084] After the test, push out the soil sample column and weigh the mass G2 of the soil sample column with an electronic scale;

[0085] 6) Collecting fluorescence scale data

[0086] After the test, the fluorescent scale on the water replenishment soil column was manually observed to record the scale H2 at the top surface of the large cylinder of the lifting base.

[0087] The calculation of submerged evaporation described in the technical solution refers to:

[0088] 1) Based on the height data of the replenishment solution, the total mass G of the replenishment solution can be obtained w ,

[0089] G w =S·(H1-H2)·ρ-S·H3,

[0090] Where: S is the inner bottom area of ​​the water replenishment soil column;

[0091] H1 is the scale of the position of the top surface of the large cylinder of the lifting base when the equipment is installed before the test;

[0092] H2 is the scale of the position of the top surface of the large cylinder of the lifting base after the test;

[0093] H3 is the height of the small cylinder of the lifting base;

[0094] (H1-H2) is the total height of the replenishment solution during the entire test period;

[0095] ρ is the solution density;

[0096] 2) The total evaporation of soil water G can be obtained by the mass of the soil sample column before and after the test and the total mass of water replenishment.

[0097] G=|G2-G1|+G W ,

[0098] Where: G1 is the mass of the soil sample column before the test;

[0099] G2 is the mass of the soil sample column after the test;

[0100] 3) The soil moisture evaporation amount W at time K can be obtained by obtaining the monitoring data of air humidity sensor No. 1 and air humidity sensor No. 2 k ,

[0101]

[0102] Where: W k is the amount of soil water evaporation at time K;

[0103] G is the total evaporation of soil water;

[0104] ω is the evaporation humidity of the soil sample column measured by air humidity sensor No. 2;

[0105] ω k It is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor at time K;

[0106] ω i It is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor at each monitoring moment;

[0107] u is the reference humidity outside the box measured by air humidity sensor No. 1;

[0108] uk It is the reference humidity outside the box measured by the No. 1 air humidity sensor at time K;

[0109] u i It is the reference humidity outside the box measured by the No. 1 air humidity sensor at each monitoring moment;

[0110] i is the evaporation monitoring time interval;

[0111] t is the total trial time.

[0112] The technical solution describes a test device for simulating submerged evaporation, comprising a light-proof box, a test cylinder, an evaporation temperature exhaust control system, a submerged evaporation monitoring system, a soil moisture and salt temperature monitoring system, a water level dynamic control system, an image acquisition system, a data acquisition system and a computer; the light-proof box is vertically mounted on the test bench through the lower bottom plate therein; the test cylinder is vertically fixedly mounted at the center of the lower bottom plate in the light-proof box; the evaporation temperature exhaust control system is mounted on the main box in the light-proof box; the No. 1 air humidity sensor in the submerged evaporation monitoring system is vertically inserted into the through hole of the sensor fixing frame outside the main box, and the No. 2 air humidity sensor is horizontally inserted into the test cylinder. 1 through hole on the water-replenishing soil column in the test cylinder; 4 insertion-type moisture, salt and temperature sensors with the same structure in the soil moisture, salt and temperature monitoring system are inserted into the soil sample through through holes No. 2 to No. 5 on the water-replenishing soil column; the water level dynamic control system is installed at the center of the lower bottom plate just below the water-replenishing soil column in the light-proof box; the image acquisition system is installed on the test bench to the right of the shooting port at the center of the right wall of the main box; the data acquisition system and the computer are installed on the test bench on the right side of the light-proof box, the data acquisition system is connected to the soil moisture, salt and temperature monitoring system line, and the computer and the data acquisition system, the image acquisition system and the PLC synchronous lifting system in the water level dynamic control system are connected.

[0113] The light-proof box described in the technical solution also includes a box, No. 1 ultraviolet lamp, No. 2 ultraviolet lamp, an embedded wall panel and a heating lamp fixing plate; the box also includes an upper top plate; the lower end of the main box is installed in the groove at the top of the lower bottom plate, and the two are dynamically matched; the top of the embedded wall panel is fixed to the bottom end surface of the upper top plate by welding, the symmetry center line of the embedded wall panel is collinear with the symmetry center line of the upper top plate, and the upper top plate is installed on the top port of the main box through the embedded wall panel, the top surface of the top port of the main box is in contact and connected with the bottom end surface of the upper top plate around the embedded wall panel, and the embedded wall panel and the top port of the main box are dynamically matched; one longitudinal end of the sensor fixing frame is fixed to the upper part of the outer side of the left box wall of the main box by welding, and one end of the heating lamp fixing plate is fixed to the upper part of the inner side of the left box wall of the main box by welding, and is located above the sensor fixing frame on the outer side of the left box wall; No. 1 ultraviolet lamp and No. 2 ultraviolet lamp are installed on the lower bottom plate at two right angles on the right side of the main box.

[0114] The test cylinder described in the technical solution also includes permeable stone, 4 screws with the same structure, 12 nuts with the same structure, a cylinder fixing platform, a partition and a fluorescent scale; the cylinder fixing platform is fixed on the outer wall of the water replenishment soil column by bonding, and the cylinder fixing platform is installed at 2 / 3 of the length of the cylinder body from the top of the water replenishment soil column; the partition is fixed to the inside of the water replenishment soil column by bonding, and the partition is installed at 2 / 3 of the length of the cylinder body from the top of the water replenishment soil column, and the permeable stone is placed on the partition inside the water replenishment soil column; the upper ends of the 4 screws with the same structure are inserted into the 4 through holes on the cylinder fixing platform on the water replenishment soil column, and a nut is set on each screw inserted into the 4 through holes on the cylinder fixing platform and located on the upper and lower sides of the cylinder fixing platform, and a nut is set on the lower end of each screw; the fluorescent scale is vertically fixed to the outer wall of the right cylinder wall of the water replenishment soil column by bonding.

[0115] Compared with the prior art, the present invention has the following beneficial effects:

[0116] 1. The water level dynamic control system of the test device for simulating submerged evaporation described in the present invention is structurally different from the traditional submerged evaporation device. The existing domestic submerged evaporation indoor test device generally sets a water replenishment cylinder outside the soil sample and manually controls the water level height in the water replenishment cylinder; the device sets a water replenishment cylinder under the soil sample, and intelligently controls the water level height in the water replenishment cylinder through the PLC synchronous jacking system, which is more flexible and convenient to operate.

[0117] 2. The water level dynamic control system of the test device for simulating submerged evaporation described in the present invention is different from the groundwater level control method of the traditional submerged evaporation device in terms of simulation method. The existing domestic submerged evaporation indoor test device generally simulates submerged evaporation under constant groundwater level by constant pressure water replenishment into the soil sample through a water replenishment cylinder; the present method can be tested through the groundwater level fluctuation data monitored in the field, and more realistically simulate the dynamic change of the groundwater level in the natural environment. The frequency and amplitude of the water level change in the test are controlled by the PLC synchronous jacking system, which is consistent with natural conditions and improves the test accuracy;

[0118] 3. The submerged evaporation monitoring system of the test device for simulating submerged evaporation described in the present invention is different from the evaporation collection method of the traditional submerged evaporation device in terms of operation mode. The existing domestic submerged evaporation indoor test device can generally only read data manually or collect soil samples to measure evaporation by drying method at various time points in the evaporation process, and the collection process is complicated and cumbersome; the method can obtain data immediately after the test based on the monitoring data of two air humidity sensors, the soil quality and water replenishment quality before and after the test, and calculate the soil evaporation data during the dynamic change of the groundwater level through manual processing, so as to obtain the submerged evaporation at any time in the evaporation process, and can realize the quantitative analysis of submerged evaporation;

[0119] 4. The experimental device for simulating submerged evaporation described in the present invention is improved in terms of observation method. The existing domestic submerged evaporation indoor experimental device generally cannot visualize the change of the water field during submerged evaporation. The light-proof box and ultraviolet lamp of the device can provide a fluorescence visualization method under dark conditions. The water replenishment soil column is made of transparent organic glass. By adding a replenishment solution mixed with fluorescent element into the water replenishment soil column, the position of the solution in the soil sample column can be observed under the irradiation of the ultraviolet lamp during the test, so that the water migration path of submerged evaporation can be observed in real time, and the process of water migration in the soil body during submerged evaporation can be truly restored. The observation is convenient, which is of great significance for the study of water migration of submerged evaporation.

[0120] 5. The water replenishment soil column of the test device for simulating submerged evaporation described in the present invention is structurally different from the traditional submerged evaporation device. The existing domestic submerged evaporation indoor test devices all have sensor holes arranged vertically on the cylinder, while the sensor holes of this device are arranged spirally on the water replenishment soil column. Compared with the vertically arranged sensor holes, the spirally arranged sensor holes can arrange more sensors at the same height, shorten the distance between measuring points, and improve the accuracy of the measurement range. At the same time, the present device can reduce the impact of artificial interference in the water migration path due to the vertical arrangement of holes, and improve the test accuracy; BRIEF DESCRIPTION OF THE DRAWINGS

[0121] The present invention will be further described below in conjunction with the accompanying drawings:

[0122] Figure 1 It is an axonometric projection view of the structural composition of a test device for simulating submerged evaporation according to the present invention;

[0123] Figure 2 for Figure 1 Sectional view at AA in the middle;

[0124] Figure 3 It is an axonometric projection view of the box structure used in the test device for simulating submerged evaporation according to the present invention;

[0125] Figure 4 for Figure 2 Axonometric projection view of the structural components at B in the middle;

[0126] Figure 5 It is an axonometric projection view of the water replenishment soil column structure used in the experimental device for simulating submerged evaporation according to the present invention;

[0127] Figure 6 A top view of the water replenishment soil column structure used in a test device for simulating submerged evaporation according to the present invention;

[0128] Figure 7 The present invention is a flowchart of a visualized test method for a test device for simulating submerged evaporation.

[0129] In the figure: 1. Main box, 2. Upper top plate, 3. Lower bottom plate, 4. Sensor fixing frame, 5. Water replenishment soil column, 6. Permeable stone, 7. Lifting base, 8. Rubber ring, 9. Nut, 10. Screw, 11. Evaporation speed control exhaust fan, 12. Evaporation temperature control heating lamp head, 13. No. 1 air humidity sensor, 14. Water and salt temperature sensor, 15. CNC hydraulic jack, 16. Data acquisition system, 17. Temperature controller, 18. Air volume controller, 19. Computer, 20. Bracket, 21. CC D microscope camera, 22. PLC synchronous lifting system, 23. No. 1 ultraviolet lamp, 24. No. 2 ultraviolet lamp, 25. No. 2 air humidity sensor, 26. Embedded wall panel, 27. Heating lamp fixing plate, 28. Cylinder fixing table, 29. Partition, 30. Light-proof box, 31. Test cylinder, 32. Evaporation temperature exhaust control system, 33. Diving evaporation monitoring system, 34. Soil moisture, salt and temperature monitoring system, 35. Water level dynamic control system, 36. Fluorescent scale, 37. Lamp connecting column. DETAILED DESCRIPTION

[0130] The present invention is described in detail below in conjunction with the accompanying drawings:

[0131] See also Figure 1 and Figure 2 The test device for simulating submerged evaporation described in the present invention includes a light-proof box 30, a test cylinder 31, an evaporation temperature and exhaust control system 32, a submerged evaporation monitoring system 33, a soil moisture and salt temperature monitoring system 34, a water level dynamic control system 35, an image acquisition system, a data acquisition system 16, and a computer 19.

[0132] See also Figure 2 and Figure 3The light-proof box 30 includes a box body (main box body 1, upper top plate 2, lower bottom plate 3), a sensor fixing frame 4, a No. 1 ultraviolet lamp 23, a No. 2 ultraviolet lamp 24, an embedded wall plate 26 and a heating lamp fixing plate 27;

[0133] The box body is composed of a main box body 1, an upper top plate 2 and a lower bottom plate 3;

[0134] The main box body 1 is a hollow rectangular shell structure with open top and bottom ends. The lower end of the main box body 1 is installed in the groove at the top of the lower bottom plate 3. The lower end of the main box body 1 can move freely up and down in the groove at the top of the lower bottom plate 3, that is, the bottom end of the main box body 1 and the top groove of the lower bottom plate 3 are dynamically matched. A square shooting opening is set at the center of the right box wall of the main box body 1. The main box body 1 is made of stainless steel plate;

[0135] The upper top plate 2 is a rectangular plate-like structural member, the length and width of the upper top plate 2 are larger than the length and width of the outer side of the top port of the main box 1, and a conical exhaust fan access port is arranged at the center of the upper top plate 2. The upper top plate 2 is made of a stainless steel plate;

[0136] The lower bottom plate 3 is a plate-type structural member with a groove at the center of a rectangle. The length and width of the groove are equal to the length and width of the outer side of the bottom end port of the main box body 1. Four circular threaded through holes with the same structural dimensions as the screw 10 are evenly arranged at the center of the lower bottom plate 3, i.e., the center of the groove. The lower bottom plate 3 is made of a stainless steel plate.

[0137] The embedded wall panel 26 is a hollow rectangular annular structural member with open top and bottom ends. The outer length and width structural dimensions of the embedded wall panel 26 are equal to the inner length and width structural dimensions of the top port of the main box body 1. The top of the embedded wall panel 26 is fixed to the bottom end surface of the upper top plate 2 by welding. The symmetry center line of the embedded wall panel 26 is colinear with the symmetry center line of the upper top plate 2. The embedded wall panel 26 is installed in the top port of the main box body 1. The embedded wall panel 26 and the top port of the main box body 1 are in dynamic fit. The embedded wall panel 26 is made of stainless steel plate.

[0138] The sensor fixing frame 4 is a rectangular parallelepiped structural member, and a sensor insertion opening is provided at the longitudinal center of the sensor fixing frame 4, and the sensor insertion opening is used to fix the No. 1 air humidity sensor 13. One end of the sensor fixing frame 4 is fixed to the upper part of the outer side of the left box wall of the main box body 1 by welding, and the material of the sensor fixing frame 4 is stainless steel;

[0139] The No. 1 ultraviolet lamp 23 and the No. 2 ultraviolet lamp 24 are two cylindrical structural members with the same structure. The No. 1 ultraviolet lamp 23 and the No. 2 ultraviolet lamp 24 are used to observe the moisture migration path of the test soil. They are common ultraviolet lamps on the market, such as the T8 / 20W ultraviolet lamp of the Gemeis brand and the 20W ultraviolet lamp of the Shellite brand.

[0140] The heating lamp fixing plate 27 is a rectangular parallelepiped structural member, and is used to fix the evaporative temperature control heating lamp 12. The length and width structural dimensions of one end of the heating lamp fixing plate 27 are equal to the dimensions of the fixing clamp opening at the tail of the lamp connecting column 37. The other end of the heating lamp fixing plate 27 is fixed to the upper part of the inner side of the left box wall of the main box body 1 by welding, and is located above the sensor fixing frame 4 on the outer side of the left box wall. The heating lamp fixing plate 27 is made of stainless steel.

[0141] The No. 1 ultraviolet lamp 23 and the No. 2 ultraviolet lamp 24 are vertically installed on the lower base plate 3 at two right angles on the right side of the main box body 1, the bottom end port of the main box body 1 is inserted into the groove of the lower base plate 3, the bottom end surface of the bottom end port of the main box body 1 is in contact with the bottom of the groove on the lower base plate 3, the bottom end port of the embedded wall panel 26 is inserted into the top end port of the main box body 1, and the top end surface of the top end port of the main box body 1 is in contact with the bottom end surface of the upper top plate 2 around the embedded wall panel 26.

[0142] See also Figure 2 , Figure 4 , Figure 5 and Figure 6 The test cylinder 31 includes a water replenishing soil column 5, a permeable stone 6, 4 screws 10 with the same structure, 12 nuts 9 with the same structure, a cylinder fixing platform 28, a partition 29 and a fluorescent scale 36;

[0143] The water replenishment soil column 5 is a cylindrical shell structure. A strip opening with an open top is arranged at the top of the left side wall of the water replenishment soil column 5. The width of the strip opening in the front-to-back direction is equal to the width of the lamp connecting column 37 of the evaporative temperature control heating lamp 12 in the front-to-back direction. The water replenishment soil column 5 is evenly provided with 5 radial through holes along the vertical spiral direction from 70 mm below the bottom of the strip opening to 2 / 3 of the length of the barrel from the top surface of the water replenishment soil column 5. From top to bottom, they are numbered 1 to 5, and the diameter of the through holes is 15 mm to 25 mm. The vertical distance between the centers of two adjacent through holes in No. 1 to No. 5 is 30 mm to 50 mm, and the horizontal distance is 50 mm. The center of No. 5 through hole is 30 mm away from the cylinder fixing platform 28, and the center of No. 1 through hole is 70 mm below the bottom of the strip opening of the water replenishment soil column 5. The center lines of No. 1 through hole and No. 5 through hole are vertical in space, and the water replenishment soil column 5 is made of organic glass;

[0144] The permeable stone 6 is a circular plate-type structural member, and the circumferential structural dimensions of the permeable stone 6 are equal to the inner wall structural dimensions of the water replenishment soil column 5. The permeable stone 6 is a common geotechnical permeable stone on the market, such as a geotechnical permeable stone of φ100*10mm produced by Tuoce Instrument Co., Ltd., and the permeable stone 6 is made of corundum;

[0145] The nut 9 is a common hexagonal nut in the market, such as a stainless steel hexagonal nut of model M12 of Jinchao brand, and the nut 9 is made of 304 stainless steel;

[0146] The screw rod 10 is a common threaded rod in the market, such as a stainless steel threaded rod of model M12 of Jinchao brand, and the screw rod 10 is made of 304 stainless steel;

[0147] The cylinder fixing platform 28 is a circular plate-type structural member, and the cylinder fixing platform 28 is used to fix the water replenishment soil column 5. The inner ring structure size of the cylinder fixing platform 28 is equal to the outer wall structure size of the water replenishment soil column 5. The cylinder fixing platform 28 is evenly provided with 4 circular threaded through holes with the same structure size as the screw 10 along the outer edge position, and the cylinder fixing platform 28 is made of organic glass;

[0148] The partition 29 is a circular plate-type structural member, and the partition 29 is used to place the permeable stone 6. The outer ring structural size of the partition 29 is equal to the inner wall structural size of the water replenishment soil column 5, and the inner ring structural size of the partition 29 is equal to the circumferential structural size of the small cylindrical structural member of the lifting base 7. The partition 29 is made of organic glass;

[0149] The fluorescent ruler 36 is composed of a transparent self-adhesive ruler and a luminous tape. The transparent self-adhesive ruler is a common self-adhesive ruler on the market, such as a transparent self-adhesive ruler sticker with a model of 50cm long * 1cm wide. The luminous tape is a common luminous tape on the market, such as a yellow-green luminous tape with a model of 3m long * 1cm wide of the Seven Colors Space brand. The transparent self-adhesive ruler is made of PVC self-adhesive stickers, and the luminous tape is made of PET self-adhesive stickers; the transparent self-adhesive ruler and the luminous tape are selected with the same width specifications, and the transparent self-adhesive ruler and the luminous tape are cut with scissors to the same length as the water replenishment soil column 5, and the transparent self-adhesive ruler is pasted on the luminous surface of the luminous tape. The luminous tape is fixed to the outer wall of the right wall of the water replenishment soil column 5 by pasting. The fluorescent ruler 36 can show a fluorescent effect under the irradiation of an ultraviolet lamp, and is used to observe the water migration height and the solution replenishment height in the soil sample column during the test;

[0150] The partition 29 is fixed inside the water replenishment soil column 5 by bonding. The partition 29 is placed at 2 / 3 of the length of the cylinder body from the top of the water replenishment soil column 5. The internal space of the water replenishment soil column 5 is divided into two parts, the upper part of the water replenishment soil column 5, and the lower part of the water replenishment soil column 5 is used to hold the soil to be tested, and the lower part of the water replenishment soil column 5 is used to hold the water replenishment solution mixed with fluorescein.

[0151] The permeable stone 6 is placed on the partition 29 inside the water replenishment soil column 5;

[0152] The cylinder fixing platform 28 is fixed on the outer wall of the water replenishment soil column 5 by bonding, and the cylinder fixing platform 28 is placed at 2 / 3 of the cylinder length from the top of the water replenishment soil column 5;

[0153] The water replenishment soil column 5 is fixed on the lower base plate 3 by four screws 10. The upper ends of the four screws 10 with the same structure are inserted into the four through holes of the barrel fixing platform 28 on the water replenishment soil column 5. The bottom ends of the four screws are screwed into the four threaded through holes with the same structure on the lower base plate 3. The two are fixedly connected. A nut 9 is set on each screw 10 inserted into the four through holes on the barrel fixing platform 28 and located on the upper and lower sides of the barrel fixing platform 28. A nut 9 is set on each screw 10 screwed into the lower base plate 3.

[0154] See also Figure 1 and Figure 2 , the evaporation temperature exhaust control system 32 includes an evaporation temperature control heating lamp 12, a lamp connecting column 37, an evaporation speed control exhaust fan 11, a temperature controller 17 and an air volume controller 18;

[0155] The evaporative temperature-controlled heating lamp 12 is a screw-type lamp holder, and the evaporative temperature-controlled heating lamp 12 uses a 50W ceramic heater of the Pates brand. The evaporative temperature-controlled heating lamp 12 can heat the soil to be tested inside the water-supplementing soil column 5;

[0156] The lamp connection column 37 has a screw thread at one end and a fixing clamp at the other end, with a cylindrical structure in the middle. The screw thread of the lamp connection column 37 is used to fix the evaporative temperature-controlled heating lamp 12. The clamping size of the fixing clamp of the lamp connection column 37 is equal to the length and width structural dimensions of the heating lamp fixing plate 27, and is used to fix the overall structure. The cylindrical structure in the middle of the lamp connection column 37 is used to connect the screw thread and the fixing clamp, and is a universal tough hose that can be rotated 360 degrees for final shaping. The screw thread of the lamp connection column 37 is screwed into the screw thread on the evaporative temperature-controlled heating lamp 12, and the fixing clamp of the lamp connection column 37 is clamped and connected to the heating lamp fixing plate 27. The lamp connection column 37 uses a 300W curved tube lamp clamp of the REPTILE STRUCTURE brand. The lamp connection column 37 is a matching standard product for the evaporative temperature-controlled heating lamp 12.

[0157] The temperature controller 17 of model WK-SM3 can control the heating temperature and heating time of the evaporation temperature control heating lamp 12, and the temperature control range of the temperature controller 17 is 5°C to 99°C;

[0158] The evaporation temperature control heating lamp 12 is connected by inserting the two live and neutral wires in the plug of the power line into the live and neutral wires in the two sockets on the temperature controller 17 socket, and the two live and neutral wires in the plug of the power line of the temperature controller 17 are connected by inserting the two live and neutral wires in the two sockets on the power socket;

[0159] The evaporative speed-controlled exhaust fan 11 of the Jiuyefeng brand model LH-100-32W has a cylindrical plug at the bottom and a fuselage at the top. The evaporative speed-controlled exhaust fan 11 can discharge the water evaporated from the soil in time. The air volume controller 18 of the model AC / DCADAPTER YYS-1202000 can control the air volume of the evaporative speed-controlled exhaust fan 11. The air volume control range of the air volume controller 18 is 0m 3 / h~280m 3 / h;

[0160] The evaporation speed-controlled exhaust fan 11 is connected to the two live and neutral wires in the female power cord of the air volume controller 18 through insertion and connection, and the two live and neutral wires in the plug on the power cord of the air volume controller 18 are inserted and connected to the live and neutral wires in the two sockets on the power socket;

[0161] See also Figure 1 , Figure 2 and Figure 5 , the diving evaporation monitoring system 33 includes a No. 1 air humidity sensor 13 and a No. 2 air humidity sensor 25;

[0162] The No. 1 air humidity sensor 13 and the No. 2 air humidity sensor 25 are two cylindrical structural parts with the same structure. The No. 1 air humidity sensor 13 and the No. 2 air humidity sensor 25 are common temperature and humidity sensors on the market, such as the model HENGKO The temperature and humidity sensor of RHT-H31, the temperature and humidity sensor of TH10S-B, the temperature and humidity sensor of B-TH-RS30, etc., the probe housings of the plug-in air humidity sensor No. 1 13 and the air humidity sensor No. 2 25 are made of stainless steel, the air humidity sensor No. 1 13 is vertically inserted into the through hole of the sensor fixing frame 4 outside the main box 1, and the air humidity sensor No. 2 25 is horizontally inserted into the through hole No. 1 on the water replenishment soil column 5, the air humidity sensor No. 1 13 and the air humidity sensor No. 2 25 adopt RS485 four-wire wiring, the red line, white line, yellow line, and green line of the RS485 four-wire wiring of the air humidity sensor No. 1 13 and the air humidity sensor No. 2 25 are respectively connected to the positive pole, negative pole, 485A, and 485B of the RS485 interface of the data acquisition and processing system 16, and the data acquisition and processing system 16 is connected to the computer 19 through a line with a USB interface;

[0163] See also Figure 1 The soil moisture, salt and temperature monitoring system 34 includes 4 inserted moisture, salt and temperature sensors 14 with the same structure. The inserted moisture, salt and temperature sensors 14 are common moisture, salt and temperature sensors on the market, such as Campbell brand moisture, salt and temperature sensors with model CR1000X and Decagon brand moisture, salt and temperature sensors with model 5TM. The 4 inserted moisture, salt and temperature sensors 14 with the same structure are inserted into the soil sample column through No. 2 to No. 5 through holes on the water replenishment soil column 5. The 4 inserted moisture, salt and temperature sensors 14 with the same structure are used to monitor the moisture content of the soil sample column in the water replenishment soil column 5. The 4 inserted moisture, salt and temperature sensors 14 with the same structure adopt RS485 four-wire wiring. The red line, white line, yellow line and green line of the RS485 four-wire wiring are respectively connected to the positive pole, negative pole, 485A and 485B of the RS485 interface of the data acquisition and processing system 16. The data acquisition and processing system 16 is connected to the computer 19 through a line with a USB interface.

[0164] See also Figure 1 , Figure 2 and Figure 4 , the water level dynamic control system 35 includes a lifting base 7, a rubber ring 8, a CNC hydraulic jack 15 and a PLC synchronous lifting system 22;

[0165] The lifting base 7 is a cylindrical structural member, which is welded by a large cylindrical structural member and a small cylindrical structural member. The lower bottom surface of the small cylindrical structural member of the lifting base 7 is arranged at the center of the top surface of the large cylindrical structural member, that is, the rotation center line of the small cylindrical structural member is collinear with the rotation center line of the large cylindrical structural member. The circumferential structural size of the small cylindrical structural member of the lifting base 7 is equal to the inner ring structural size of the partition 29, and the circumferential structural size of the large cylindrical structural member of the lifting base 7 is slightly smaller than the inner ring structural size of the water replenishment soil column 5. The lifting base 7 is used to push the replenishment solution doped with fluorescein in the water replenishment soil column 5 into the soil to be tested, and the lifting base 7 is made of stainless steel;

[0166] The rubber ring 8 is a circular ring structure with a groove shape of equal cross section. The rubber ring 8 is a common rubber ring in the market. The diameter and thickness of the rubber ring 8 are the same as the diameter and thickness of the large cylindrical structure of the lifting base 7. For example, a fire-fighting joint rubber ring with a model of DN100 is selected. The rubber ring 8 plays a sealing role;

[0167] The CNC hydraulic jack 15 is a cylindrical structural member, and the CNC hydraulic jack 15 is a general-purpose CNC hydraulic jack on the market, such as a CNC hydraulic jack of model F50 / 200 produced by Zhonggong Company;

[0168] The PLC synchronous lifting system 22 is a general-purpose PLC synchronous lifting system on the market, such as the PLC synchronous lifting system of model S50 / 160 produced by Zhonggong Company and model S50 / 200 produced by Zhonggong Company, etc. The PLC synchronous lifting system is used to control the lifting, lowering and pressure maintenance of the CNC hydraulic jack 15;

[0169] The lifting base 7 is inserted into the bottom of the water replenishment soil column 5, and the inner wall of the groove of the rubber ring 8 is fixed to the outer cylindrical surface of the large cylindrical structure of the lifting base 7 by bonding, and the outer ring wall of the rubber ring 8 is in contact with the inner cylinder wall of the water replenishment soil column 5; the bottom surface of the CNC hydraulic jack 15 is fixed to the lower base plate 3 by welding, and the bottom end surface of the lifting base 7 is fixedly connected to the top surface of the piston head of the CNC hydraulic jack 15 by welding. The inlet and outlet oil interfaces of the CNC hydraulic jack 15 are connected to the oil inlet and outlet of the electric hydraulic pump station of the PLC synchronous jacking system 22 through hydraulic hoses. The PLC synchronous jacking system 22 is connected to the computer 19 through a line with a USB interface. The control of the CNC hydraulic jack 15 can be controlled on the touch screen of the PLC synchronous jacking system 22, and can also be controlled on the PLC signal processing software of the computer 19;

[0170] See also Figure 1 , the image acquisition system includes a bracket 20 and a CCD microscope camera 21;

[0171] The bracket 20 is a common camera bracket in the market, such as a tripod of the Ulanzi brand model MT-08;

[0172] The CCD microscope camera 21 is a common microscope camera on the market, such as the LM2000 CCD camera of the Ribo brand, the iXon Ultra 897 high-sensitivity CCD camera of the AVDOR brand, etc. The CCD camera can still maintain a high image resolution in areas with insufficient light, and has a higher imaging speed. The CCD microscope camera 21 is used to monitor the water migration in the water replenishment soil column 5;

[0173] The bracket 20 is fixedly connected to the CCD microscope camera 21 by screws, and the CCD microscope camera 21 is connected to the computer 19 by a line with a USB interface. The CCD microscope camera 21 is located on the right side of the shooting port at the center of the right wall of the main box 1. The CCD microscope camera 21 can be set to take pictures at a fixed time, and this function can be controlled by the shooting software installed in the computer 19;

[0174] The data acquisition system 16 is a rectangular parallelepiped structure, which is a common dynamic signal test analyzer on the market, such as the dynamic signal test analyzer model NUXI-1004 / 8 produced by Top Measurement and Control Company, etc., which contains an integrated information collection and processing unit and is a standard product on the market. The data acquisition system 16 and the computer 19 are installed on the right side of the main box 1;

[0175] The computer 19 is a market standard desktop computer, such as a DELL brand model 3681 desktop computer;

[0176] The light-proof box 30 is vertically mounted on the test bench through the lower base plate 3 therein;

[0177] The test cylinder 31 is vertically installed at the center of the lower bottom plate 3 in the light-proof box 30. The test cylinder 31 is connected to the lower bottom plate 3 of the light-proof box 30 through the cylinder fixing platform 28 thereon by using 4 screws 10 with the same structure and 12 nuts 9 with the same structure. The longitudinal symmetry center line of the main box 1 in the light-proof box 30 is collinear with the longitudinal symmetry center line of the test cylinder 31.

[0178] The evaporation temperature control heating lamp 12 of the evaporation temperature exhaust control system 32 is located at the top of the water replenishment soil column 5 in the test cylinder 31, and the universal flexible hose on the side of the lamp connecting column 37 close to the screw port is inserted into the strip-shaped opening on the water replenishment soil column 5, and the fixing clip at the tail of the lamp connecting column 37 is clamped and connected with the heating lamp fixing plate 27 on the inner side of the left box wall of the main box body 1 in the light-proof box body 30;

[0179] The evaporation speed control exhaust fan 11 of the evaporation temperature exhaust control system 32 is installed at the center of the top of the main box body 1 in the light-proof box body 30, and the cylindrical socket at the bottom of the evaporation speed control exhaust fan 11 is inserted into the conical exhaust fan access port at the center of the upper top plate 2 in the main box body 1, and the temperature controller 17 and the air volume controller 18 are installed on the rear side of the main box body 1;

[0180] In the submersible evaporation monitoring system 33, the No. 1 air humidity sensor 13 is vertically inserted into the through hole of the sensor fixing frame 4 outside the main box 1, and the No. 2 air humidity sensor 25 is horizontally inserted into the No. 1 through hole on the water replenishment soil column 5;

[0181] The soil moisture, salt and temperature monitoring system 34 is located inside the test cylinder 31. Four insertion-type moisture, salt and temperature sensors 14 with the same structure in the soil moisture, salt and temperature monitoring system 34 are horizontally inserted into the soil samples in the No. 2 to No. 5 through holes of the water replenishment soil column 5.

[0182] The water level dynamic control system 35 is located directly below the water replenishment soil column 5 in the light-proof box 30. The bottom surface of the CNC hydraulic jack 15 in the water level dynamic control system 35 is fixed to the lower bottom plate 3 by welding, and the top piston head is fixed to the lower bottom surface of the lifting base 7 by welding.

[0183] See also Figure 7 The visualization test method using the test device for simulating diving evaporation is as follows:

[0184] 1. Experimental Preparation

[0185] 1) Preliminary test

[0186] Through preliminary tests, the proportional relationship between the lifting height of the PLC synchronous lifting system 22 and the water level change height of the water replenishment soil column 5 is determined, and the proportional coefficient μ of different soil layers is recorded. i (i = sub-sand layer, sub-clay layer, medium-fine sand layer, coarse sand gravel layer, etc.); the preliminary test method is as follows:

[0187] (1) Control the numerically controlled hydraulic jack 15 to slowly rise through the PLC synchronous lifting system 22, push the fluorescent solution into the first soil layer at the bottom of the soil sample column, stop lifting, observe and record the height h1 of the fluorescent in the soil sample column;

[0188] (2) Control the numerically controlled hydraulic jack 15 through the PLC synchronous lifting system 22 to inject the fluorescein solution to 20 mm, stop lifting, and observe and record the height h2 of the fluorescein in the soil sample column;

[0189] (3) Calculate the proportional coefficient μ1 of the first soil layer, μ1 = 20 / (h2-h1);

[0190] (4) If the soil sample column has multiple different soil layers, the proportional coefficient μ i =20 / (h i-2 -h i-1 ), after recording the h of the first soil layer 1-2 After that, the PLC synchronous lifting system 22 is used to control the numerically controlled hydraulic jack 15 to slowly rise, and the fluorescent solution is pushed into the second soil layer at the bottom of the soil sample column. The lifting is stopped, and the height h of the fluorescent substance in the soil sample column is observed and recorded. 2-1 , and then inject to 20mm, stop lifting, observe and record the height of the fluorescent substance in the soil sample column h 2-2 , calculate the proportional coefficient μ2 of the second soil layer, μ2=20 / (h 2-2 -h 2-1 ); the third soil layer μ3=20 / (h 3-2 -h 3-1 ) until the last layer of soil;

[0191] 2) Collection and processing of groundwater level fluctuation monitoring data

[0192] Monitoring wells are used to monitor the dynamics of groundwater levels in the field over a period of time. Groundwater level fluctuation monitoring data are collected through groundwater level monitoring instruments. The data include monitoring time and groundwater level height. The data can also be published in existing literature. The obtained monitoring data needs to be processed as follows:

[0193] (1) The groundwater level fluctuation monitoring data is made into an EXCEL table - groundwater level fluctuation monitoring data table. In the table header, column A is the monitoring time in minutes, column B is the groundwater level height in millimeters, and column C is the soil quality of the soil layer where the groundwater level is located, including sub-sand layer, sub-clay layer, medium-fine sand layer, coarse sand gravel layer, etc. The 1st row, 2nd row, 3rd row...nth row in the table are the actual monitoring data values;

[0194] (2) Record the overall height h of the field monitoring soil layer and scale it to the size of the water replenishment soil column 5. The height of the soil sample column in the water replenishment soil column 5 is recorded as h b , calculate the proportionality coefficient e, e = h b / h;

[0195] (3) In the groundwater level fluctuation monitoring data table, add column D as the control data of the PLC synchronous jacking system 22, and enter the formula in column D of the table: The unit is mm / min. The positive value of the result is to control the PLC synchronous lifting system 22 to rise, and the negative value is to control the PLC synchronous lifting system 22 to fall.

[0196] 3) Preparation of soil sample column

[0197] Soil samples can be selected from undisturbed soil or remolded soil in the field;

[0198] (1) Prepare soil sample columns according to the actual soil thickness of the field site according to the proportional coefficient e. The height range of the soil sample column is preferably 2 cm above the top surface of the permeable stone 6 to the No. 2 through hole of the water replenishment soil column tube 5. If it is too high, it will affect the accuracy of the top moisture, salt and temperature sensor in monitoring the surface. If it is too low, the soil layer will be cracked when the top moisture, salt and temperature sensor is inserted. Fill the mold with the same size as the water replenishment soil column tube 5. Fill in the soil layer consistent with the field site, such as sub-sand layer, sub-clay layer, medium-fine sand layer, coarse sand gravel layer, etc. in layers, or just fill in one soil layer. The specific number of soil layers to be filled depends on how many soil layers are involved in the groundwater fluctuation range, and compact it every 5 cm height.

[0199] (2) After all the soil samples are filled, push the soil sample column out of the mold and weigh the mass G1 of the soil sample column using an electronic scale;

[0200] 4) Calculate static water level

[0201] According to the field monitoring data, the variation range of the groundwater level depth can be known. In the experiment, the water level with the smallest groundwater level fluctuation during the monitoring period is taken as the static water level H. j , calculate the static water level h of the test soil sample column according to the proportional coefficient e j ,h j =H j ×e;

[0202] 2. Equipment Installation

[0203] 1) The numerically controlled hydraulic jack 15 is placed at the center of the lower base plate 3, the bottom of the water replenishment soil column 5 is mounted on the lifting base 7, and the cylinder fixing platform 28 and the lower base plate 3 are fixedly connected by four screws 10. The thickness H3 of the small cylinder of the lifting base 7 is measured with a ruler, and a layer of vaseline is evenly applied inside the wall of the water replenishment soil column 5 and above the partition 29 to block moisture;

[0204] 2) Pour the replenishing solution mixed with fluorescein into the replenishing soil column 5 until the liquid level reaches the position of the partition 29, and then place the permeable stone 6 on the partition 29. At this time, manually observe the fluorescent scale 36 on the replenishing soil column 5 and record the scale H1 at the top surface of the large cylinder of the lifting base 7. This scale is used to calculate the amount of solution replenishment after the test.

[0205] 3) The prepared soil sample column is placed into the water replenishment soil column tube 5, and the bottom of the soil sample column is in contact with the permeable stone 6;

[0206] 4) inserting four water, salt and temperature sensors 14 into the soil sample through through holes No. 2 to No. 5 in the water replenishment soil column 5, and inserting No. 2 air humidity sensor 25 into through hole No. 1 on the water replenishment soil column 5;

[0207] 5) Place the No. 1 UV lamp 23 and the No. 2 UV lamp 24 at the two corners on the right side of the lower base plate 3, and then install the main box 1 on the lower base plate 3;

[0208] 6) The evaporation temperature control heating lamp 12 is placed inside the water replenishment soil column 5, the lamp connecting column 37 is inserted into the strip-shaped opening on the water replenishment soil column 5, and the fixing clip at the tail of the lamp connecting column 37 clamps the heating lamp fixing plate 27;

[0209] 7) Insert the No. 1 air humidity sensor 13 into the sensor fixing bracket 4;

[0210] 8) The upper top plate 2 is buckled onto the top of the main box 1; then the bottom of the evaporation speed-controlled exhaust fan 11 is inserted into the conical opening in the center of the upper top plate 2;

[0211] 9) The CCD microscope camera 21 is placed on the right side of the shooting port on the right wall of the main box body 1;

[0212] 3. Test instrument parameter setting

[0213] 1) Groundwater level fluctuation model setting

[0214] Import the results of column D in the groundwater level fluctuation monitoring data table into the computer 19 and transmit them to the PLC synchronous lifting system 22 ( The unit is mm / min), the digital signal is converted into an electrical signal, and the PLC synchronous jacking system 22 is controlled to dynamically change the water level through the change of the current signal. The PLC synchronous jacking system 22 can control the height of the CNC hydraulic jack 15 rising and falling per minute, thereby simulating the actual change of the groundwater level in the field over time;

[0215] 2) Sensor data collection interval setting

[0216] (1) Power on the data acquisition system 16:

[0217] (2) The data acquisition system 16 inputs the sampling interval through the timer in the computer 19. The interval can be set arbitrarily, and the shortest interval is 1 minute. The interval is set according to the total test time. When the test time is a few hours or a few days, the collection interval is 1 minute to 20 minutes. When the test time is a few weeks or a few months, the collection interval is 60 minutes to 120 minutes.

[0218] 3) Temperature controller settings

[0219] The temperature controller 17 is set to simulate the temperature and time of the sun's irradiation on the ground surface in the wild. The temperature controller 17 can manually control the heating temperature and heating time of the evaporative temperature control heating lamp 12. The control panel of the temperature controller 17 has a display screen and five buttons. The display screen can display the current temperature of the evaporative temperature control heating lamp 12 and the heating time of the temperature controller 17; the five buttons are a mode switching button, a start operation (increase button, decrease button), and a stop operation (increase button, decrease button); the specific setting is completed by the following steps:

[0220] (1) The temperature controller 17 is powered on;

[0221] (2) Press the mode switch button to switch the mode to the temperature mode and adjust the heating temperature of the evaporation temperature control heating lamp 12;

[0222] (3) Press the increase button and the decrease button of the start operation to adjust the required heating temperature of the temperature-controlled heating lamp 12. The temperature control range of the temperature controller 17 is 5°C to 99°C. The setting of the heating temperature can refer to the average surface temperature of the land in each season;

[0223] (4) Press the mode switch button to switch the mode to the time mode and adjust the heating time of the evaporation temperature control heating lamp 12;

[0224] (5) Press the increase button and decrease button of the start operation to adjust the evaporation temperature control heating lamp 12 to the required power-on time;

[0225] (6) If you need to set a power-on and power-off cycle, after the power-on time is set, press the increase button and the decrease button of the stop operation to adjust the power-off time of the evaporative temperature control heating lamp 12. The control time range of the temperature controller 17 is 1min to 9999min. The power-on and power-off time can refer to the actual daily solar radiation time, such as a 4-hour power-on and power-off cycle or an 8-hour power-on and 16-hour power-off cycle; you can also choose a power-on time of 30min to 480min and a power-off time of 60min to 960min according to the test design;

[0226] 4) Air volume controller settings

[0227] The air volume controller 18 is set to simulate the wind speed in the wild, and at the same time, the water evaporated from the soil can be discharged in time. In the wild, the wind will blow away the water evaporated from the soil, thereby accelerating the evaporation of surface water; the air volume controller 18 can manually control the air volume of the evaporation speed control exhaust fan 11. There is a knob on the control panel of the air volume controller 18, and there is an indicator light on the knob. The specific setting is completed by the following steps:

[0228] (1) The air volume controller 18 is powered on:

[0229] (2) Turn the knob clockwise to the desired air volume. The position of the indicator light indicates the current air volume. The air volume control range of the air volume controller 18 is 0m 3 / h~280m 3 / h, the wind volume can be set by referring to the meteorological data of surface wind speed in each season;

[0230] 5) CCD microscope camera shooting interval setting

[0231] (1) Power on the CCD microscope camera 21:

[0232] (2) The CCD microscope camera 21 inputs the sampling interval through the timer in the computer 19. The interval can be set arbitrarily, and the shortest interval is 1 minute. The interval is set according to the total test time. When the test time is a few hours or a few days, the collection interval is 1 minute to 20 minutes. When the test time is a few weeks or a few months, the collection interval is 60 minutes to 120 minutes.

[0233] 4. Start the experiment

[0234] 1) No. 1 ultraviolet lamp 23, No. 2 ultraviolet lamp 24, PLC synchronous lifting system 22 and computer 19 are powered on;

[0235] 2) The PLC synchronous lifting system 22 controls the numerically controlled hydraulic jack 15 to slowly rise, pushing the fluorescein solution into the soil sample column to the static water level height h j Stop lifting, and during the lifting process, control the hydraulic jack 15 to rise at a speed of 1 mm / min to 10 mm / min. The rising speed should not be too fast to avoid water flow impact causing pores and cracks in the soil sample column;

[0236] 3) The data acquisition system 16, the temperature controller 17, and the air volume controller 18 are powered on, the CCD microscope camera 21 is turned on, and the test is started;

[0237] 5. Data Collection

[0238] 1) Collect moisture, salt and temperature sensor data

[0239] (1) The moisture, salt and temperature sensor 14 records the change data and change curve of the moisture content, conductivity and temperature at different heights of the test soil sample column over time. In the curve, the x-axis is time and the y-axis is moisture content, conductivity and temperature;

[0240] (2) The moisture, salt and temperature sensor 14 collects data through the AD chip in the data acquisition system 16. The AD chip uses a sampling pulse sequence to extract a series of discrete sample values ​​from the analog signals of water content, conductivity and temperature and converts them into digital signals. The moisture, salt and temperature sensor 14 transmits the data to the computer 19 through the data acquisition system 16;

[0241] 2) Collect air humidity sensor data

[0242] (1) No. 2 air humidity sensor 25 and No. 1 air humidity sensor 13 respectively record the change data and change curve of the evaporation humidity of the soil sample column and the reference humidity outside the main box 1 over time, in which the x-axis is time and the y-axis is humidity;

[0243] (2) The air humidity sensor No. 2 25 and the air humidity sensor No. 1 13 collect data through the AD chip in the data acquisition system 16. The AD chip extracts a series of discrete sample values ​​from the humidity analog signal using a sampling pulse sequence and converts them into digital signals. The air humidity sensor No. 2 25 and the air humidity sensor No. 1 13 transmit the data to the computer 19 through the data acquisition system 16;

[0244] 3) Collect CCD microscope image data

[0245] During the test, the numerically controlled hydraulic jack 15 will push the replenishment solution mixed with fluorescein in the replenishment soil column 5 into the soil sample column. Under the irradiation of the ultraviolet lamp, the fluorescein solution will show a bright fluorescent green color. The position with fluorescent green is the water migration height of the soil sample column in the upper part of the replenishment soil column 5 and the solution height in the lower part of the replenishment soil column 5. The specific collection steps are as follows:

[0246] (1) The CCD microscope camera 21 takes real-time images of the right side wall of the water replenishment soil column 5;

[0247] (2) The CCD microscope camera 21 collects image information through the CCD image sensor in the body. The CCD microscope camera 21 first converts the optical signal into an electrical signal, and then converts the electrical signal into a digital signal through the analog-to-digital converter in the body. After the digital signal is formed, the microprocessor compresses the signal and converts it into an image file and stores it in the computer 19;

[0248] (3) The test operator can manually read the scale of the fluorescent scale 36 on the water replenishment soil column 5 at each moment through the image stored in the computer 19 to obtain the water migration height and solution replenishment height in the soil sample column. This method solves the problem of difficult observation during the submersible evaporation test and realizes visualization of the entire test process.

[0249] 4) Collect total test time data

[0250] When the test is completed, the start time and end time are recorded by the data acquisition system 16, and the total test time t is calculated manually;

[0251] 5) Collect soil sample column quality data

[0252] After the test, push out the soil sample column and weigh the mass G2 of the soil sample column with an electronic scale;

[0253] 6) Collecting fluorescence scale data

[0254] After the test, the fluorescent scale 36 on the water replenishment soil column 5 is manually observed to record the scale H2 at the position of the top surface of the large cylinder of the lifting base 7;

[0255] 6. Calculation of diving evaporation

[0256] Based on the data obtained in the experiment, the phreatic evaporation during the dynamic change of groundwater level can be calculated according to the following method;

[0257] 1) Based on the height data of the replenishment solution, the total mass G of the replenishment solution can be obtained w ,

[0258] G w =S·(H1-H2)·ρ-S·H3,

[0259] Where: S is the inner bottom area of ​​the water replenishment soil column 5;

[0260] H1 is the scale of the position of the top surface of the 7 large cylinders of the lifting base when the equipment is installed before the test;

[0261] H2 is the scale of the position of the top surface of the 7 large cylinders of the lifting base after the test;

[0262] H3 is the height of the small cylinder of the lifting base 7;

[0263] (H1-H2) is the total height of the replenishment solution during the entire test period;

[0264] ρ is the solution density;

[0265] 2) The total evaporation of soil water G can be obtained by the mass of the soil sample column before and after the test and the total mass of water replenishment.

[0266] G=|G2-G1|+G W ,

[0267] Where: G1 is the mass of the soil sample column before the test;

[0268] G2 is the mass of the soil sample column after the test;

[0269] 3) The soil moisture evaporation amount W at time K can be obtained by obtaining the monitoring data of air humidity sensor No. 1 13 and air humidity sensor No. 2 25 k ,

[0270]

[0271] Where: W k is the amount of soil water evaporation at time K;

[0272] G is the total evaporation of soil water;

[0273] ω is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor 25;

[0274] ω k is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor 25 at time K;

[0275] ω i is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor 25 at each monitoring moment;

[0276] u is the reference humidity outside the box measured by the No. 1 air humidity sensor 13;

[0277] u k is the reference humidity outside the box measured by the No. 1 air humidity sensor 13 at time K;

[0278] u i is the reference humidity outside the box measured by the No. 1 air humidity sensor 13 at each monitoring moment;

[0279] i is the evaporation monitoring time interval;

[0280] t is the total trial time.

[0281] The above indoor test method can be used to obtain the evaporation of soil at each moment, and then analyze the evaporation of soil in the area where the soil sample is located. When designing the test, the evaporation of soil can be compared by changing the soil layer structure, temperature conditions, air volume conditions and the salinity of the replenishment solution, and the influence of different soil layer structures, temperature conditions, air volume conditions and the salinity of the replenishment solution on the evaporation of soil can be obtained.

[0282] Through this method, the phreatic evaporation during the dynamic change of groundwater level can be studied more scientifically and rationally, and the whole process of phreatic evaporation test can be visualized.

Claims

1. A visual test method for a test device simulating submerged evaporation, characterized in that The test device for simulating submerged evaporation comprises a light-proof box (30), a test cylinder (31), an evaporation temperature and exhaust control system (32), a submerged evaporation monitoring system (33), a soil moisture and salt temperature monitoring system (34), a water level dynamic control system (35), an image acquisition system, a data acquisition and processing system (16) and a computer (19); The light-proof box (30) is vertically mounted on the test bench through the lower bottom plate (3) therein; the test cylinder (31) is vertically fixedly mounted at the center of the lower bottom plate (3) in the light-proof box (30); the evaporation temperature exhaust control system (32) is mounted on the main box (1) in the light-proof box (30); the No. 1 air humidity sensor (13) in the submersible evaporation monitoring system (33) is vertically inserted into the through hole of the sensor fixing frame (4) outside the main box (1), and the No. 2 air humidity sensor (25) is horizontally inserted into the No. 1 through hole on the water replenishment soil column (5) in the test cylinder (31); the four inserted moisture and salt temperature sensors (34) of the same structure in the soil moisture and salt temperature monitoring system (34) are arranged on the same surface of the test cylinder (31); the moisture and salt temperature sensors (34) of ... 14) is inserted into the soil sample through the No. 2 to No. 5 through holes on the water replenishment soil column (5); the water level dynamic control system (35) is installed at the center of the lower bottom plate (3) directly below the water replenishment soil column (5) in the light-proof box (30); the image acquisition system is installed on the test bench to the right of the shooting port at the center of the right box wall of the main box (1); the data acquisition and processing system (16) and the computer (19) are installed on the test bench on the right side of the light-proof box (30), the data acquisition and processing system (16) is connected to the soil water, salt and temperature monitoring system (34) by wire, and the computer (19) and the data acquisition and processing system (16), the image acquisition system and the PLC synchronous lifting system (22) in the water level dynamic control system (35); The light-proof box (30) further comprises a box, a No. 1 ultraviolet lamp (23), a No. 2 ultraviolet lamp (24), an embedded wall plate (26) and a heating lamp fixing plate (27); The box body also includes an upper top plate (2); The lower end of the main box (1) is installed in the groove at the top of the lower base plate (3), and the two are in dynamic fit; the top of the embedded wall plate (26) is fixed to the bottom end surface of the upper top plate (2) by welding, the symmetry center line of the embedded wall plate (26) is colinear with the symmetry center line of the upper top plate (2), the upper top plate (2) is installed on the top end port of the main box (1) through the embedded wall plate (26), and the top end surface of the top end port of the main box (1) is in contact with the bottom end surface of the upper top plate (2) around the embedded wall plate (26). The embedded wall plate (26) and the top end port of the main box body (1) are in a dynamic fit; one longitudinal end of the sensor fixing frame (4) is fixed to the upper part of the outer side of the left box wall of the main box body (1) by welding, and one end of the heating lamp fixing plate (27) is fixed to the upper part of the inner side of the left box wall of the main box body (1) by welding, and is located above the sensor fixing frame (4) on the outer side of the left box wall; the No. 1 ultraviolet lamp (23) and the No. 2 ultraviolet lamp (24) are installed on the lower bottom plate (3) at two right angles on the right side of the main box body (1); The test cylinder (31) further comprises a permeable stone (6), four screw rods (10) of the same structure, twelve nuts (9) of the same structure, a cylinder fixing platform (28), a partition (29) and a fluorescent scale (36); The cylinder fixing platform (28) is fixed on the outer wall of the water replenishment soil column (5) by bonding, and the cylinder fixing platform (28) is installed at a distance of 2 / 3 of the cylinder length from the top of the water replenishment soil column (5); the partition (29) is fixed inside the water replenishment soil column (5) by bonding, and the partition (29) is installed at a distance of 2 / 3 of the cylinder length from the top of the water replenishment soil column (5), and the permeable stone (6) is placed on the partition (29) inside the water replenishment soil column (5); 4 The upper ends of the screw rods (10) of the same structure are inserted into the four through holes on the cylinder fixing platform (28) on the water replenishment soil column (5), and a nut (9) is respectively set on each screw rod (10) inserted into the four through holes on the cylinder fixing platform (28) and located on the upper and lower sides of the cylinder fixing platform (28), and a nut (9) is set on the lower end of each screw rod (10); the fluorescent scale (36) is vertically fixed to the outer side wall of the right cylinder wall of the water replenishment soil column (5) by gluing; The water level dynamic control system (35) comprises a lifting base (7); the lifting base (7) is welded from a large cylindrical structure and a small cylindrical structure, and the lower bottom surface of the small cylindrical structure of the lifting base (7) is arranged at the center of the top surface of the large cylindrical structure; the lifting base (7) is inserted into the bottom of the water replenishment soil column (5), and the bottom end surface of the lifting base (7) is fixedly connected to the top surface of the piston head of the CNC hydraulic jack (15) by welding; The steps of the visualization test method of the test device for simulating diving evaporation are as follows: 1) Test preparation: (1) Preliminary test: a. The PLC synchronous lifting system (22) controls the CNC hydraulic jack (15) to slowly rise, push the fluorescein solution into the first soil layer at the bottom of the soil sample column, stop lifting, observe and record the height h1 of the fluorescein in the soil sample column; b. The PLC synchronous lifting system (22) controls the CNC hydraulic jack (15) to inject the fluorescein solution into the 20mm, stop lifting, observe and record the height h2 of the fluorescein in the soil sample column; c. Calculate the proportional coefficient μ1 of the first soil layer, μ1=20 / (h2-h1); d. If the soil sample column has multiple different soil layers, the proportional coefficient μ i =20 / (h i-2 -h i-1 ), after recording the h of the first soil layer 1-2 After that, the PLC synchronous lifting system (22) is used to control the numerical control hydraulic jack (15) to slowly rise, and the fluorescent solution is pushed into the second soil layer at the bottom of the soil sample column. The lifting is stopped, and the height h of the fluorescent substance in the soil sample column is observed and recorded. 2-1 , and then inject to 20mm, stop lifting, observe and record the height of the fluorescent substance in the soil sample column h 2-2 , calculate the proportional coefficient μ2 of the second soil layer, μ2=20 / (h 2-2 -h 2-1 ); the third soil layer μ3=20 / (h 3-2 -h 3-1 ) until the last layer of soil; (2) Collection and processing of groundwater level fluctuation monitoring data: Monitoring wells are used to monitor the dynamics of groundwater levels in the field over a period of time. The groundwater level fluctuation monitoring data is collected through groundwater level monitoring instruments or using data published in existing literature. The data includes monitoring time and groundwater level height. The obtained monitoring data needs to be processed as follows: a. Make the groundwater level fluctuation monitoring data into an EXCEL table - groundwater level fluctuation monitoring data table. In the table header, column A is the monitoring time in min, column B is the groundwater level height in mm, column C is the soil quality of the soil layer where the groundwater level is located, including sub-sand layer, sub-clay layer, medium-fine sand layer and coarse sand gravel layer. Rows 1, 2, 3...n in the table are the actual monitoring data values; b. Record the overall height h of the field monitoring soil layer, scaled to the scale of the water replenishment soil column (5), and the height of the soil sample column in the water replenishment soil column (5) is recorded as h b , calculate the proportionality coefficient e, e = h b / h; c. In the groundwater level fluctuation monitoring data table, add column D as the control data of the PLC synchronous lifting system (22), and enter the formula in column D of the table: The unit is mm / min. A positive value of the result controls the PLC synchronous lifting system (22) to rise, and a negative value controls the PLC synchronous lifting system (22) to fall. (3) preparing soil sample columns; (4) Calculate static water level: According to the field monitoring data, the variation range of the groundwater level depth can be known. In the experiment, the water level with the smallest groundwater level fluctuation during the monitoring period is taken as the static water level H. j , calculate the static water level h of the test soil sample column according to the proportional coefficient e j ,h j =H j ×e; 2) Equipment installation; 3) Test instrument parameter settings: (1) Groundwater level fluctuation model setting The results of column D in the underground water level fluctuation monitoring data table are imported into a computer (19) and transmitted to a PLC synchronous lifting system (22), where the digital signal is converted into an electrical signal. The PLC synchronous lifting system (22) is controlled to dynamically change the water level through the change of the current signal. The CNC hydraulic jack (15) controls the height of rise and fall per minute through the PLC synchronous lifting system (22), thereby simulating the change of the actual underground water level in the field over time. (2) Sensor data collection interval setting a. Data acquisition and processing system (16) power supply: b. The data acquisition and processing system (16) inputs the sampling interval through the timer in the computer (19). The interval is set according to the total test time. When the test time is a few hours or a few days, the sampling interval is 1 min to 20 min. When the test time is a few weeks or a few months, the sampling interval is 60 min to 120 min. (3) Temperature controller settings The specific settings are completed through the following steps: a. The temperature controller (17) is powered on; b. Press the mode switch button to switch the mode to the temperature mode and adjust the heating temperature of the evaporation temperature control heating lamp (12); c. Press the increase button and decrease button to start the operation, adjust the evaporation temperature control heating lamp (12) to the required heating temperature, the temperature controller (17) has a temperature control range of 5 ° C ~ 99 ° C, the heating temperature is set according to the average surface temperature of the land in each season to determine; d. Press the mode switch button to switch the mode to the time mode and adjust the heating time of the evaporation temperature control heating lamp (12); e. Press the increase button and decrease button to start the operation and adjust the evaporation temperature control heating lamp (12) to the required power-on time; f. If you need to set the power-on and power-off cycles, after the power-on time is set, press the increase button and the decrease button of the stop operation to adjust the power-off time of the evaporation temperature control heating lamp (12). The control time range of the temperature controller (17) is 1min to 9999min. The power-on and power-off time is determined according to the actual daily solar exposure time; (4) Air volume controller settings The specific settings are completed through the following steps: a. Turn on the power of air volume controller (18): b. Turn the knob clockwise to the desired air volume. The position of the indicator light indicates the current air volume. The air volume control range of the air volume controller (18) is 0m 3 / h~280m 3 / h, the wind volume is set according to the meteorological data of the surface wind speed in each season; (5) CCD microscope camera shooting interval setting a. Power on the CCD microscope camera (21): b. The CCD microscope camera (21) inputs the sampling interval through the timer in the computer (19), The interval time can be set arbitrarily, and the shortest interval time is 1 minute. The interval time setting is determined according to the total test time. When the test time is a few hours or a few days, the collection interval time is 1 minute to 20 minutes. When the test time is a few weeks or a few months, the collection interval time is 60 minutes to 120 minutes. 4) Start the experiment; 5) Data collection: (1) Collecting moisture, salt and temperature sensor data a. The moisture, salt and temperature sensor (14) records the moisture content, conductivity and temperature change data and change curve of the test soil sample column at different heights over time, in which the x-axis is time and the y-axis is moisture content, conductivity and temperature; b. The moisture, salt and temperature sensor (14) collects data through the AD chip in the data acquisition and processing system (16). The AD chip uses a sampling pulse sequence to extract a series of discrete sample values ​​from the analog signals of water content, conductivity and temperature and converts them into digital signals. The moisture, salt and temperature sensor (14) transmits the data to the computer (19) through the data acquisition and processing system (16); (2) Collecting air humidity sensor data a. No. 2 air humidity sensor (25) and No. 1 air humidity sensor (13) respectively record the change data and change curve of the evaporation humidity of the soil sample column and the reference humidity outside the main box (1) over time, in which the x-axis is time and the y-axis is humidity; b. The air humidity sensor No. 2 (25) and the air humidity sensor No. 1 (13) collect data through the AD chip in the data collection and processing system (16). The AD chip extracts a series of discrete sample values ​​from the humidity analog signal using a sampling pulse sequence and converts them into digital signals. The air humidity sensor No. 2 (25) and the air humidity sensor No. 1 (13) transmit the data to the computer (19) through the data collection and processing system (16); (3) Collecting CCD microscope image data During the test, the numerically controlled hydraulic jack (15) pushes the replenishment solution mixed with fluorescein in the replenishment soil column (5) into the soil sample column. Under the irradiation of the ultraviolet lamp, the fluorescein solution will show a bright fluorescent green color. The position with fluorescent green is the water migration height of the soil sample column in the upper part of the replenishment soil column (5) and the solution height in the lower part of the replenishment soil column (5). The specific collection steps are as follows: a. A CCD microscope camera (21) captures the right wall image of the water replenishment soil column (5) in real time; b. The CCD microscope camera (21) collects image information through the CCD image sensor in the body. The CCD microscope camera (21) first converts the optical signal into an electrical signal, and then converts the electrical signal into a digital signal through the analog-to-digital converter in the body. After the digital signal is formed, the microprocessor compresses the signal and converts it into an image file and stores it in the computer (19); c. The test operator can manually read the scale of the fluorescent scale (36) on the water replenishment soil column (5) at each moment through the image stored in the computer (19) to obtain the water migration height and solution replenishment height in the soil sample column; (4) Collecting total test time data When the test is completed, the start time and end time are recorded by the data acquisition and processing system (16), and the total test time t is calculated manually; (5) Collect soil sample column quality data After the test, push out the soil sample column and weigh the mass G2 of the soil sample column with an electronic scale; (6) Collecting fluorescence scale data After the test, the fluorescent scale (36) on the water replenishment soil column (5) is manually observed to record the scale H2 at the position of the top surface of the large cylinder of the lifting base (7); 6) Calculation of diving evaporation: (1) Based on the height data of the replenishment solution, the total mass G of the replenishment water can be obtained w , G w =S·(H1-H2)·ρ-S·H3, Where: S is the inner bottom area of ​​the water replenishment soil column (5); H1 is the scale of the position of the top surface of the large cylinder of the lifting base (7) when the equipment is installed before the test; H2 is the scale mark at the position of the top surface of the large cylinder of the lifting base (7) after the test; H3 is the height of the small cylinder of the lifting base (7); (H1-H2) is the total height of the replenishment solution during the entire test period; ρ is the solution density; (2) The total evaporation of soil water G can be obtained by the mass of the soil sample column before and after the test and the total mass of water replenishment. G=|G2-G1|+G W , Where: G1 is the mass of the soil sample column before the test; G2 is the mass of the soil sample column after the test; (3) The soil moisture evaporation amount W at time K can be obtained by using the monitoring data of air humidity sensor No. 1 (13) and air humidity sensor No. 2 (25). k , Where: W k is the amount of soil water evaporation at time K; G is the total evaporation of soil water; ω is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor (25); ω k is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor (25) at time K; ω i is the evaporation humidity of the soil sample column measured by the No. 2 air humidity sensor (25) at each monitoring moment; u is the reference humidity outside the box measured by the No. 1 air humidity sensor (13); u k is the reference humidity outside the box measured by the No. 1 air humidity sensor (13) at time K; u i is the reference humidity outside the box measured by the No. 1 air humidity sensor (13) at each monitoring moment; i is the evaporation monitoring time interval; t is the total trial time.

2. A visual test method for a test device simulating submerged evaporation according to claim 1, characterized in that , the equipment installation mentioned here refers to: 1) A numerically controlled hydraulic jack (15) is placed at the center of the lower base plate (3), the bottom of the water replenishment soil column (5) is mounted on the lifting base (7), and the cylinder fixing platform (28) and the lower base plate (3) are fixedly connected by four screws (10). The thickness H3 of the small cylinder of the lifting base (7) is measured with a ruler, and a layer of vaseline is evenly applied inside the wall of the water replenishment soil column (5) and above the partition (29) to block moisture; 2) Pour the replenishing water solution mixed with fluorescein into the replenishing soil column (5) until the liquid level reaches the position of the partition (29), and then place the permeable stone (6) on the partition (29). At this time, manually observe the fluorescent scale (36) on the replenishing soil column (5) to record the scale H1 at the top surface of the large cylinder of the lifting base (7); 3) The prepared soil sample column is placed into the water replenishment soil column tube (5), and the bottom of the soil sample column is in contact with the permeable stone (6); 4) inserting four water, salt and temperature sensors (14) into the soil sample through through holes No. 2 to No. 5 in the water replenishment soil column (5), and inserting the No. 2 air humidity sensor (25) into the No. 1 through hole on the water replenishment soil column (5); 5) UV lamp No. 1 (23) and UV lamp No. 2 (24) are placed at the two corners on the right side of the lower base plate (3), and then the main box (1) is installed on the lower base plate (3); 6) The evaporative temperature-controlled heating lamp (12) is placed inside the water-replenishing soil column (5), the lamp connecting column (37) is inserted into the strip-shaped opening on the water-replenishing soil column (5), and the fixing clip at the tail of the lamp connecting column (37) clamps the heating lamp fixing plate (27); 7) Insert the No. 1 air humidity sensor (13) into the sensor fixing bracket (4); 8) The upper top plate (2) is buckled onto the top of the main housing (1); then the bottom of the evaporation speed-controlled exhaust fan (11) is inserted into the conical opening at the center of the upper top plate (2); 9) The CCD microscope camera (21) is placed on the right side of the shooting port on the right wall of the main box body (1).

Images