River-groundwater seepage simulation system and method considering seawater backflow influence

Abstract

The application relates to the field of surface water-underground water simulation test devices, in particular to a river-underground water seepage simulation system and method considering the influence of seawater backflow, which comprises an observation tank, the observation tank comprises a seepage area in the middle in the transverse direction, and a saltwater chamber and a freshwater chamber are arranged on the two sides of the seepage area respectively; one of the peripheral walls of the observation tank is a transparent observation side peripheral wall; a first water supply mechanism is used for inputting freshwater with a first color into the freshwater chamber; a second water supply mechanism is used for outputting the freshwater; a tide generating device is used for simulating a tide generating process and outputting saltwater with a second color; the freshwater output by the second water supply mechanism and the saltwater output by the tide generating device are mixed in a mixing chamber and then input into the saltwater chamber; a camera is used for shooting the picture displayed by the whole observation side peripheral wall in real time; the system does not simply simulate the influence of seawater on underground water, but comprehensively considers the influence of salt tide on underground water after the salt tide is mixed with surface water, and is more practical.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surface water-groundwater simulation test devices, in particular to a river-groundwater seepage simulation system and method considering the influence of seawater upwelling. BACKGROUND

[0002] Seawater intrusion is an environmental geological disaster problem, however, in the past, the research on seawater intrusion of aquifer has locked the research area near the coastline, in addition to the phenomenon of seawater intrusion of underground aquifer near the coastline, there is also the phenomenon of seawater upwelling along the river into the sea, that is, under the driving of tides and other factors, seawater enters the estuary and upwells along the river to form salt tide, and the salt tide pollutes the groundwater through the riverbank; In recent years, it has been found that the salinity of estuary salt tide changes with tides, and this salinity change will change the solute transport and water cycle between surface water and aquifer in the estuary, affect the saltwater distribution of aquifer, and cause “deep” intrusion of coastal aquifer, which will cause salinization of underground fresh water and soil salinization, and seriously threaten the coastal groundwater environment. The existing technology is limited to the simulation test of the interaction between surface water and groundwater, and does not consider the influence of seawater upwelling change on surface water-groundwater seepage, therefore, how to design a simulation system capable of simulating and monitoring the dynamic change of surface water-groundwater process under the influence of seawater upwelling has become a technical problem to be solved by the technical personnel in the field. SUMMARY

[0003] In order to solve at least one of the technical problems mentioned in the background, the purpose of the present application is to provide a river-groundwater seepage simulation system and method considering the influence of seawater upwelling.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical scheme.

[0005] On the one hand, the present application provides a river-groundwater seepage simulation system considering the influence of seawater upwelling, comprising:

[0006] An observation tank, the observation tank includes a seepage zone in the middle in the transverse direction, and a saltwater chamber and a freshwater chamber respectively arranged on both sides of the seepage zone; the seepage zone is filled with seepage medium; at least one of the peripheral walls of the observation tank extends in the transverse direction to form an observation side peripheral wall, and the observation side peripheral wall is a transparent structure;

[0007] A first water supply mechanism for inputting freshwater with a first color into the freshwater chamber to simulate groundwater;

[0008] A second water supply mechanism for outputting freshwater to simulate surface water;

[0009] The tide generating device comprises a driving mechanism and a first container for receiving salt water with a second color, the second color being different from a first color; the first container comprises a first water outlet; the driving mechanism is used to drive the water level in the first container to periodically rise and fall in the form of a sine wave.

[0010] A mixing chamber comprising an output port in communication with the salt water chamber, the mixing chamber being configured such that the fresh water output by the second water supply mechanism and the salt water output by the first water outlet are mixed in the mixing chamber and then flow into the salt water chamber through the output port.

[0011] A camera with a lens facing the observation side peripheral wall for real-time shooting of the picture displayed on the entire observation side peripheral wall.

[0012] Compared with the prior art, the application has the following advantages:

[0013] In the application, the tide generating device is used to simulate the process of seawater tide generation, so that the salt water (i.e. simulated seawater) is periodically input into the mixing chamber in the form of a sine wave and mixed with the fresh water output by the second water supply mechanism; at this time, the tide generating device simulates seawater, the second water supply mechanism simulates river surface water, and the first water supply mechanism simulates groundwater.

[0014] The mixing chamber is used to mix the salt water output by the tide generating device and the fresh water output by the second water supply mechanism before they enter the observation tank, so as to simulate the process of salt tide invasion.

[0015] The fresh water output by the first water supply mechanism has a first color, and the salt water output by the tide generating device has a second color different from the first color, so that the distribution of the colors can be used to intuitively observe the simulated salt tide and the diffusion distribution interface of the simulated groundwater (i.e. the fresh water output by the first water supply mechanism) in the seepage zone, which is equivalent to tracking the seepage interface by changing the color, and recording the changes of the interface in real time by the camera, so as to show the influence of seawater upstream changes on surface water-groundwater seepage.

[0016] It can be seen that the simulation system provided by the application not only simulates the influence of seawater on groundwater, but also considers the influence of salt tide on groundwater after mixing with surface water, which is more realistic.

[0017] As an optional embodiment of the present application, the driving mechanism comprises a saltwater tank for storing saltwater with the second color, a first pump for pumping the saltwater in the saltwater tank into the first container, a reflux pipe, and a driving assembly for driving the reflux pipe and the first container to move vertically relative to each other in a sinusoidal manner.

[0018] As an optional embodiment of the present application, the driving assembly comprises a winch and a cable wound on the winch, the cable being fixed to the first container, and the winch winding and unwinding the cable to drive the first container to move vertically relative to the reflux pipe.

[0019] As an optional embodiment of the present application, the mixing chamber has a cylindrical structure, and a helical blade extending axially in the mixing chamber; and / or a flow slowing component is arranged in the outlet of the mixing chamber to slow down the flow of the liquid out of the outlet of the mixing chamber.

[0020] As an optional embodiment of the present application, a one-way valve is arranged between the outlet of the mixing chamber and the saltwater chamber, and the one-way valve is configured to allow the saltwater output by the outlet of the mixing chamber to flow into the saltwater chamber in one direction.

[0021] As an optional embodiment of the present application, a first sensor capable of detecting the salinity is arranged in the outlet of the mixing chamber; and / or a plurality of second sensors capable of detecting the salinity are arranged in the infiltration area.

[0022] As an optional embodiment of the present application, the first water supply mechanism comprises a first water tank for storing freshwater with the first color and a second pump for pumping the freshwater in the first water tank into the freshwater chamber; and / or the second water supply mechanism comprises a second water tank for storing freshwater and a third pump for pumping the freshwater in the second water tank into the mixing chamber.

[0023] As an optional embodiment of the present application, a pre-buried pipe for introducing pollutants is arranged in the infiltration medium of the infiltration area; or the second water supply mechanism comprises a second water tank for storing freshwater and a third pump for pumping the freshwater in the second water tank into the mixing chamber, and the saltwater tank or the second water tank contains pollutants with a third color; the third color is different from the first color and the second color.

[0024] As an optional embodiment of the present application, overflow ports are arranged on the saltwater chamber and the freshwater chamber.

[0025] In another aspect, the application also provides a river-groundwater seepage simulation method considering seawater backflow effect, which is performed by using the river-groundwater seepage simulation system considering seawater backflow effect; the method specifically comprises the following steps:

[0026] S1, pre-saturation: starting the first water supply mechanism to continuously introduce fresh water with a first color into the fresh water chamber;

[0027] S2, after the first water supply mechanism works for a period of time, starting the tide generating device to introduce salt water with a second color into the mixing chamber through the first container, and starting the second water supply mechanism to introduce fresh water into the mixing chamber; the salt water and fresh water introduced into the mixing chamber are mixed in the mixing chamber and then input into the salt water chamber through the output port of the mixing chamber;

[0028] S3, real-time shooting the picture displayed by the observation side wall of the observation tank by using the camera.

[0029] Other advantages and effects of the application are specifically explained in the specific implementation mode and the part of the drawings.

[0030] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the application, nor to limit the scope of the application. Other features of the application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0031] The above and other objects, features and advantages of the example embodiments of the application will be more apparent from the following detailed description read in conjunction with the accompanying drawings, in which several embodiments of the application are shown by way of example, and in which:

[0032] In the drawings, identical or corresponding reference numerals indicate identical or corresponding parts.

[0033] Figure 1 The structural schematic diagram of the application is shown;

[0034] Figure 2 The flow chart of the application is shown;

[0035] Figure 3 The structural schematic diagram of the tide generating device of the application is shown;

[0036] Figure 4 The structural schematic diagram of the mixing chamber of the application is shown;

[0037] Figure 5 The axial sectional view of the mixing chamber of the application is shown.

[0038] Explanation of figure numbers:

[0039] 1, observation tank; 11, seepage area; 110, embedded pipe; 111, sampling port; 112, second sensor; 12, saltwater chamber; 120, second water inlet; 121, first overflow port; 13, freshwater chamber; 130, first water inlet; 131, second overflow port; 14, stainless steel mesh;

[0040] 2, first water supply mechanism; 21, first water tank; 22, second pump;

[0041] 3, second water supply mechanism; 31, second water tank; 32, third pump; 33, valve; 34, flow meter;

[0042] 4, camera;

[0043] 5, tide generating device; 51, first container; 511, first water outlet; 512, water inlet; 52, driving mechanism; 521, saltwater tank; 522, first pump; 523, return pipe; 524, driving assembly; 5241, winch; 5242, cable; 5243, fixed pulley; 5244, rack;

[0044] 6, barrel; 60, mixing chamber; 61, output port; 62, first input port; 63, second input port; 64, helical blade; 65, slow flow component; 66, one-way valve; 67, first sensor. DETAILED DESCRIPTION

[0045] In order to make the purpose, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0046] Embodiment 1

[0047] In the estuary area, seawater is driven by multiple factors such as tides, enters the estuary and forms salt tide along the river, and the salt tide pollutes the groundwater through the riverbank, which seriously threatens the coastal groundwater environment. In recent years, it has been found that the salinity of salt tide in the estuary changes with the tides, and this salinity change will change the solute transport and water cycle between the surface water and the aquifer in the estuary, and affect the saltwater distribution in the aquifer.

[0048] Therefore, the influence of the mixing of salt tide and surface river water on groundwater in the estuary needs to be fully considered. Based on this, the present embodiment aims to provide a river-aquifer seepage simulation system considering the influence of seawater upwelling, that is, considering the influence of the river invaded by salt tide on groundwater.

[0049] In combination with Figures 1-5As shown, this system mainly includes an observation tank 1, a first water supply mechanism 2, a second water supply mechanism 3, a tide generating device 5, a mixing chamber 60, a camera 4, etc. The following is a detailed explanation of each component.

[0050] like Figure 1 As shown, the observation tank 1 includes a seepage zone 11 in the middle along the transverse direction, and a saline water chamber 12 and a fresh water chamber 13 respectively located on both sides of the seepage zone 11; Figure 1 For example, the lateral direction claimed in this embodiment can be understood as the length direction of the seepage channel, that is, the left and right direction. Specifically, the seepage zone 11 is located in the middle of the observation tank 1, while the saline water chamber 12 is located on the left side of the seepage zone 11 and the fresh water chamber 13 is located on the right side of the seepage zone 11.

[0051] The seepage zone 11 is filled with a seepage medium, for example, a transparent porous medium made of 0.3mm-0.6mm fused silica glass beads is filled to a height of 50cm and compacted in layers (saturated with deionized water every 10cm). At this time, the seepage zone 11 filled with the seepage medium is equivalent to simulating the aquifer medium of estuary groundwater, and the subsequent saltwater intrusion simulation process is carried out in the seepage zone 11.

[0052] In order to visually observe the scene displayed on the interface of the seepage zone 11 during the saltwater intrusion process, in this embodiment, at least one of the peripheral walls of the observation tank 1 extends laterally to form an observation side peripheral wall, wherein the observation side peripheral wall is a transparent structure, and the seepage zone 11, the saltwater chamber 12 and the freshwater chamber 13 can be observed through the observation side peripheral wall.

[0053] As a specific implementation method, the observation tank 1 is a transparent acrylic tank with a length of 2m × width of 0.5m × height of 0.6m. At this time, the entire observation tank 1 is a transparent structure, which includes four peripheral walls, and the front peripheral wall is selected as the observation side peripheral wall.

[0054] like Figure 1 As shown, the observation tank 1 is divided into three zones by a 40-mesh stainless steel mesh 14: a saline water chamber 12 (20cm wide) on the left, a seepage zone 11 (160cm wide) in the middle, and a freshwater chamber 13 (20cm wide) on the right. Specifically, the 40-mesh stainless steel mesh 14 serves as a boundary between adjacent zones of the saline water chamber 12, seepage zone 11, and freshwater chamber 13, thus preventing the seepage medium in the seepage zone 11 from collapsing into the saline water chamber 12 and the freshwater chamber 13.

[0055] The lens of the camera 4 is directed towards the observation side wall, i.e. the lens of the camera 4 is directed towards the front side wall of the observation tank 1, and the shooting range thereof at least includes the whole observation side wall; thus, the picture displayed by the camera 4 in real time by shooting the whole observation side wall can be understood as the picture displayed by the observation side wall, which is the picture of the saltwater chamber 12, the seepage area 11 and the freshwater chamber 13 on the observation side wall.

[0056] As shown in Figure 1 , the first water supply mechanism 2 is used for inputting freshwater with a first color into the freshwater chamber 13 to simulate underground water; in some embodiments, in combination with Figure 2 , the first water supply mechanism 2 includes a first water tank 21 for storing freshwater with the first color and a second pump 22 for pumping the freshwater in the first water tank 21 into the freshwater chamber 13; as shown in Figure 1 , a first water inlet 130 is arranged at the bottom of the freshwater chamber 13, the water outlet of the second pump 22 is communicated with the first water inlet 130, and the water inlet of the second pump 22 is communicated with the first water tank 21; the freshwater in the first water tank 21 is pumped into the freshwater chamber 13 by the second pump 22, and the freshwater in the freshwater chamber 13 gradually seeps into the seepage area 11, so as to simulate the underground water distributed in the seepage area 11.

[0057] As shown in Figure 1 , the second water supply mechanism 3 is used for outputting freshwater, and the output freshwater is used for simulating surface water; in some embodiments, as shown in Figure 2 , the second water supply mechanism 3 includes a second water tank 31 for storing freshwater and a third pump 32 for pumping the freshwater in the second water tank 31 into the mixing chamber 60; specifically, the water inlet of the third pump 32 is communicated with the second water tank 31, and the water outlet of the third pump 32 is communicated with the mixing chamber 60.

[0058] In combination with Figure 3 , the tide generating device 5 is mainly used for simulating seawater, i.e. salt tide, under the action of tide; specifically, the tide generating device 5 includes a driving mechanism 52 and a first container 51 for receiving saltwater with a second color, wherein the saltwater mainly simulates seawater, and the second color is different from the first color; for example, the first color is red, and the second color is yellow-green; specifically, sodium fluorescein (50 mg / L) is added to the saltwater; rhodamine B (10 mg / L) is added to the freshwater in the first water tank 21; thus, the saltwater (i.e. salt tide) output by the tide generating device 5 and the freshwater (i.e. underground water) output by the first water tank 21 have different colors, so that the distribution of the two-phase fluid interface can be observed according to the color distribution of the seepage area 11.

[0059] , the tide generating device 5 includes a driving mechanism 52 and a first container 51 for receiving saltwater with a second color, wherein the saltwater mainly simulates seawater, and the second color is different from the first color; for example, the first color is red, and the second color is yellow-green; specifically, sodium fluorescein (50 mg / L) is added to the saltwater; rhodamine B (10 mg / L) is added to the freshwater in the first water tank 21; thus, the saltwater (i.e. salt tide) output by the tide generating device 5 and the freshwater (i.e. underground water) output by the first water tank 21 have different colors, so that the distribution of the two-phase fluid interface can be observed according to the color distribution of the seepage area 11. Figure 3As shown, the bottom of the first container 51 is provided with a first water outlet 511, which is mainly used for outputting the salt water in the first container 51; the driving mechanism 52 is used for driving the water level in the first container 51 to periodically rise and fall in the form of a sine wave, that is, to simulate the process of sea tide.

[0060] In some embodiments, the specific structure of the tide generating device 5 is that the driving mechanism 52 comprises a salt water tank 521, a first pump 522, a reflux pipe 523 and a driving assembly 524.

[0061] The salt water tank 521 is mainly used for storing salt water with a second color, that is, adding fluorescein sodium (50 mg / L) in the salt water in the salt water tank 521, so that the salt water has the second color.

[0062] The water inlet end of the first pump 522 is in communication with the salt water tank 521, and the water outlet end of the first pump 522 is in communication with the upper water inlet 512 of the upper portion of the first container 51, and the salt water in the salt water tank 521 is extracted into the first container 51 through the first pump 522.

[0063] In some embodiments, the first container 51 has a whole cylindrical structure with an open upper end and a closed lower end; the reflux pipe 523 has a straight circular pipe structure; wherein the reflux pipe 523 is movably arranged on the lower wall of the first container 51, so that the reflux pipe 523 and the first container 51 can move relatively in the vertical direction, which can be understood as the axial direction of the first container 51; the relative movement between the reflux pipe 523 and the first container 51 can be, for example, Figure 3 As shown, the reflux pipe 523 is fixedly retained by a support, and the first container 51 can move vertically, so as to realize the vertical relative movement between the two; of course, in other alternative embodiments, the first container 51 can be fixedly retained, and the reflux pipe 523 can move vertically.

[0064] In addition, the upper end of the reflux pipe 523 is located in the first container 51 as an overflow end, and the lower end of the reflux pipe 523 is connected to the salt water tank 521 as a backwater end, for example, the lower end of the reflux pipe 523 is suspended above the salt water tank 521 or inserted into the upper portion of the salt water tank 521, so that when the water level of the first container 51 exceeds the upper end of the reflux pipe 523, the excess water will flow back to the salt water tank 521 through the reflux pipe 523, so that the water level in the first container 51 is basically maintained at the position of the upper end of the reflux pipe 523; the water level in the first container 51 is equivalent to the liquid column height between the upper end of the reflux pipe 523 and the bottom wall of the first container 51, which is denoted as the water level H, which can be understood that the water level H is not constant, but changes with the vertical movement of the first container 51; the first container 51 outputs the salt water to the mixing chamber 60 through the first water outlet 511 at the liquid level height of the water level H.

[0065] The vertical movement of the first container 51 relative to the return pipe 523 is configured such that the return pipe 523 and the first container 51 are driven by the drive assembly 524 to move relatively vertically in a periodic sine wave manner.

[0066] For example, such as Figure 3 As shown, the first container 51 is driven by the drive component 524 to perform a sinusoidal motion (amplitude ±20cm) relative to the return pipe 523 during a semi-diurnal tidal cycle. The 12.4-hour cycle simulates the tidal characteristics of the estuary dominated by the M2 tidal constituent. Specifically, the change in water level H can be calculated using the following formula: H(t) = H0 + 15·sin(2πt / 12.4); where t is time and H0 is the initial liquid level height in the first container 51, representing the initial sea level height.

[0067] In some embodiments, such as Figure 3 As shown, the drive assembly 524 can be specifically constructed as follows: the drive assembly 5244 includes a frame 5244, fixed pulleys 5243, a winch 5241, and a cable 5242 wound on the winch 5241. The cable 5242 is fixed to the first container 51. The winch 5241 winds and unwinds the cable 5242 to drive the first container 51 to move vertically relative to the return pipe 523. Specifically, at least two fixed pulleys 5243 are provided and fixed on the frame 5244 to serve as the cable 5242. Guiding; one end of the cable 5242 is fixed to the reel of the winch 5241, and the other end is fixed to the first container 51. When the winch 5241 winds up the cable 5242, the cable 5242 will pull the first container 51 upward. When the winch 5241 releases the cable 5242, the first container 51 will automatically descend under its own weight and the weight of the salt water inside. In this way, the first container 51 is raised and lowered, thereby controlling the water level H in the first container 51 to move in a sinusoidal motion, simulating the occurrence of tides.

[0068] The mixing chamber 60 is mainly used to mix the saline water output from the first container 51 and the fresh water output from the second water supply unit 3, to simulate the mixing process of saline water and surface water; specifically, in some embodiments, such as Figure 4 As shown, a closed cylinder 6 is provided, and the internal space of the cylinder 6 forms a mixing chamber 60.

[0069] like Figure 4 As shown, the cylinder 6 has two input ports on one side, namely the first input port 62 and the second input port 63, and an output port 61 on the other side.

[0070] like Figure 2As shown, the first inlet 62 is connected to the outlet of the third pump 32 via a pipeline, allowing the third pump 32 to draw fresh water from the second water tank 31 and enter the mixing chamber 60 through the first inlet 62. Furthermore, a valve 33 (e.g., a ball valve) and a flow meter 34 for monitoring flow rate are also provided on the pipeline connecting the first inlet 62 and the third pump 32. In this embodiment, the first pump 522, the second pump 22, and the third pump 32 can all be peristaltic pumps.

[0071] The second inlet 63 is connected to the first outlet 511. The saline water in the first container 51 flows into the mixing chamber 60 through the first outlet 511 and the second inlet 63 in sequence, so as to mix with the fresh water input by the second water supply mechanism 3 (i.e. the second water tank 31) in the mixing chamber 60.

[0072] In some embodiments, the overall height of the cylinder 6 is lower than the height of the first outlet 511, so that the saline water in the first container 51 can flow into the mixing chamber 60 under the action of gravity.

[0073] like Figure 1 As shown, the bottom of the saline water chamber 12 has a second inlet 120, and the outlet 61 of the cylinder 6 is connected to the second inlet 120 through a pipeline. This allows the fresh water output from the second water supply mechanism 3 to mix with the saline water output from the first outlet 511 in the mixing chamber 60 before flowing back into the saline water chamber 12 through the outlet 61, thus simulating the saline mixing process. The outlet 61 is higher than the second inlet 120.

[0074] In addition, to prevent water in the saline water chamber 12 from flowing back into the mixing chamber 60, a one-way valve 66 is provided on the pipeline connecting the second inlet 120 and the outlet 61. The one-way valve 66 is configured to allow saline water output from the outlet 61 of the mixing chamber 60 to enter the saline water chamber 12 in one direction, and to stop it in the opposite direction.

[0075] To improve the mixing effect of fresh water and salt water in the mixing chamber 60, in some embodiments, such as Figure 4 As shown, the mixing chamber 60 has a cylindrical structure, and a spiral blade 64 extending along the axial direction of the mixing chamber 60 is provided inside the mixing chamber 60. In this way, as the fresh water and salt water flow forward in the mixing chamber 60, a swirling flow will be formed, thereby improving the mixing effect of the two.

[0076] Furthermore, in order to ensure that the fresh water and salt water have sufficient mixing time within the mixing chamber 60 and to prevent them from flowing out of the outlet 61 before they have had time to mix, in some embodiments, combined with Figure 5As shown, the output port 61 of the mixing chamber 60 is provided with a flow slowing component 65 for slowing the flow of liquid from the output port 61 of the mixing chamber 60, for example, the output port 61 is filled with a sponge buffer layer with a porosity of 85% as the flow slowing component 65, the flow speed of the water output by the output port 61 is slowed by the sponge buffer layer to ensure that the fresh water and salt water have sufficient time to mix in the mixing chamber 60.

[0077] In addition, in order to ensure that the salt water chamber 12 and the fresh water chamber 13 have a stable water level into the seepage area 11, in some embodiments, as shown, Figure 1 As shown, the salt water chamber 12 and the fresh water chamber 13 are each provided with an overflow port, and for the sake of distinction, the overflow port on the salt water chamber 12 is referred to as the first overflow port 121, and the overflow port on the fresh water chamber 13 is referred to as the second overflow port 131.

[0078] When the liquid level in the corresponding water chamber (i.e. the fresh water chamber 13 and the salt water chamber 12) reaches the position of the overflow port, it will be discharged outside through the overflow port, so that the water level in the corresponding water chamber is kept at the position of the corresponding overflow port, so as to ensure that the water chamber has a constant water level into the seepage area 11.

[0079] In this embodiment, the reason for setting the salt water chamber 12 instead of directly connecting the output port 61 of the mixing chamber 60 to the seepage area 11 is that by setting the salt water chamber 12, a stable liquid level is formed in the salt water chamber 12, and the salt water in the salt water chamber 12 and the seepage area 11 are in surface contact, so that the salt water in the salt water chamber 12 can flow uniformly in the horizontal direction to the seepage area 11; if the salt water chamber 12 is not set and the output port 61 of the mixing chamber 60 is directly connected to the seepage area 11, the salt water output by the mixing chamber 60 and the seepage area 11 are in point contact, so that the salt water is difficult to flow uniformly into the seepage area 11.

[0080] The role of the fresh water chamber 13 is to ensure that the fresh water in the fresh water chamber 13 has a stable liquid level seeping into the seepage area 11, so that the fresh water in the fresh water chamber 13 can seep into the seepage area 11 with a stable flow field to simulate underground water.

[0081] In this embodiment, in actual work:

[0082] The fresh water with the first color output by the first water supply mechanism 2 flows into the fresh water chamber 13 and then gradually seeps into the seepage area 11 from the fresh water chamber 13 to simulate underground water, and the underground water at this time is equivalent to having the first color.

[0083] The tide generating device 5 outputs saltwater with a second color to simulate saltwater tides, and the second water supply device 3 outputs freshwater to simulate surface water. The saltwater tide and surface water enter the mixing chamber 60 and mix to form saltwater mixed water, which at this time is equivalent to having a second color. The saltwater mixed water flows into the saltwater chamber 12 and then gradually seeps into the seepage zone 11 to interact with groundwater. Since the first color and the second color are different, obvious saltwater patches (saltwater patches can also be understood as color blocks) will be displayed on the observation side wall. The camera 4 records the position, shape, and size of the saltwater patches, as well as the shape and width changes of the saltwater-freshwater interface in real time.

[0084] Among them, camera 4 preferably adopts a high-speed camera with 100 frames per second and is equipped with a 532nm narrowband filter to enhance the contrast of fluorescent tracer and record the migration of dye.

[0085] In addition, such as Figure 5 As shown, a first sensor 67 capable of detecting salinity is provided in the output port 61 of the mixing chamber 60. The first sensor 67 is preferably located downstream of the slow-flow component 65 and is used to acquire the salinity data of the saline mixed water output from the output port 61.

[0086] In addition, such as Figure 1 As shown, a plurality of second sensors 112 capable of detecting salinity can also be provided in the seepage zone 11 to acquire salinity data at different locations in the seepage zone 11. The first sensor 67 and the second sensor 112 can be online conductivity sensors.

[0087] In some embodiments, in order to test the migration of pollutants during the seepage process, in some embodiments, a pre-embedded pipe 110 for introducing pollutants is buried in the seepage medium of the seepage zone 11; or pollutants are pre-injected into the saline tank 521.

[0088] Whether to inject pollutants into the seepage zone 11 through the pre-buried pipe 110 or to pre-add pollutants to the saline water tank 521 depends on the specific test scenario to be simulated. For example, if the simulation is of the migration of pollutants in groundwater under the influence of saline tide, then the pollutants are injected into the seepage zone 11 through the pre-buried pipe 110; if the simulation is of the migration of pollutants carried by seawater tides in the seepage zone 11 during the seepage process, then the pollutants are pre-injected into the saline water tank 521.

[0089] The migration of pollutants can be obtained through one of the following two methods:

[0090] The first way is to dye the pollutants so that the pollutants have a third color which is different from the first color and the second color. For example, the saltwater tank 521 or the second water tank 31 has mixed pollutants with the third color. During the test, the migration path of the color block with the third color can be observed.

[0091] The second way is not to dye the pollutants, but to set a plurality of sampling ports 111 in the seepage area 11, and the sampling ports 111 are adapted to be removed. Specifically, the sampling ports 111 can be set in 6 layers, and the vertical spacing between the layers is 8 cm, and there are 5 sampling ports 111 in each layer. Sampling is performed in the seepage area 11 through the sampling ports 111, and after sampling, the concentration of the pollutants in the sample is detected, and the migration of the pollutants is judged by the concentration of the pollutants in each area.

[0092] Embodiment 2

[0093] In combination Figures 1-5 As shown in the figure, the embodiment also provides a river-groundwater seepage simulation method considering the influence of seawater backflow. The method provided by the embodiment is performed by using the river-groundwater seepage simulation system considering the influence of seawater backflow provided in Embodiment 1. The system has been described in detail in Embodiment 1, and will not be described again here.

[0094] The method provided by the embodiment includes the following steps:

[0095] First, the preparation work is performed:

[0096] The fresh water of the simulated river water (i.e. surface water) is injected into the second water tank 31, and the conductivity of the fresh water is < 500 μS / cm.

[0097] The seawater, i.e. saltwater, is configured in the saltwater tank 521, and the color agent with the second color is added to the seawater. In the configured seawater, the NaCl concentration is 28 g / L, and the conductivity is approximately 45 mS / cm.

[0098] The color agent with the first color is added to the fresh water in the first water tank 21.

[0099] After the preparation is completed, the following operations are performed:

[0100] S1, pre-saturation: start the first water supply mechanism 2 to continuously inject the fresh water with the first color into the fresh water chamber 13, for example, continuously inject water for 24 hours, so that the seepage area 11 is filled with the fresh water output by the first water supply mechanism 2.

[0101] S2, when the first water supply mechanism 2 works for a period of time (for example, 24 hours), the tidal generator 5 is started, the first container 51 is connected to the mixing chamber 60 to introduce salt water with the second color, and the second water supply mechanism 3 is started to introduce fresh water into the mixing chamber 60; the salt water and fresh water introduced into the mixing chamber 60 are mixed in the mixing chamber 60 and then input into the salt water chamber 12 through the output port 61 of the mixing chamber 60.

[0102] S3, the camera 4 is used to real-time capture the picture displayed on the observation side of the observation tank 1, and the position, shape, size of the salt water, and the shape and width change of the salt-fresh water interface are recorded by the camera 4, so that the influence of the salt tide on the groundwater after mixing with the surface water can be obtained; thus, the seepage of the river (i.e., the surface water) and the groundwater under the influence of the seawater upwelling can be simulated.

[0103] Of course, if the migration of pollutants also needs to be considered, the pollutants can be injected into the salt water tank 521 or the seepage area 11. The migration of the pollutants can be obtained by the method described in embodiment 1.

[0104] It should be understood that various forms of the flow shown above can be used to reorder, add or delete steps. For example, the steps described in the present application can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in the present application can be achieved, which is not limited herein.

[0105] In addition, the terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0106] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A river-groundwater seepage simulation system considering the influence of seawater backflow, characterized by, The application relates to a tidal observation device. The device comprises: an observation tank, which comprises a middle seepage area in the transverse direction, and a saltwater chamber and a freshwater chamber arranged on the two sides of the seepage area respectively; the seepage area is filled with seepage medium; at least one of the peripheral walls of the observation tank extends in the transverse direction to form an observation side peripheral wall, and the observation side peripheral wall is transparent; a first water supply mechanism for inputting freshwater with a first color into the freshwater chamber to simulate underground water; a second water supply mechanism for outputting freshwater to simulate surface water; a tide generating device, which comprises a driving mechanism and a first container for receiving saltwater with a second color, and the second color is different from the first color; the first container comprises a first water outlet; the driving mechanism is used for driving the water level in the first container to periodically rise and fall in the form of a sine wave; a mixing chamber, which comprises an output port communicated with the saltwater chamber, and the mixing chamber is configured to mix the freshwater output by the second water supply mechanism and the saltwater output by the first water outlet in the mixing chamber, and then the mixed water flows into the saltwater chamber through the output port; the mixing chamber is formed by the internal space of a closed cylinder, one side of the cylinder is provided with two input ports, i.e. a first input port and a second input port, and the other side is provided with an output port; the first input port is communicated with the second water supply mechanism; the second input port is communicated with the first water outlet; 2. The river-groundwater seepage simulation system considering seawater intrusion influence according to claim 1, characterized by, a camera, which is used for shooting the picture displayed on the whole observation side peripheral wall in real time.

3. The river-groundwater seepage simulation system considering seawater backflow influence according to claim 2, characterized by, The driving mechanism comprises a saltwater tank for storing saltwater with the second color, a first pump, a reflux pipe and a driving assembly; the first pump is used for pumping the saltwater in the saltwater tank into the first container; the reflux pipe is arranged in the first container, one end of the reflux pipe is located in the first container, and the other end is connected with the saltwater tank; the reflux pipe and the first container can move relatively in the vertical direction; and the driving assembly is used for driving the reflux pipe and the first container to move relatively in the vertical direction in the form of a sine wave.

4. The river-groundwater seepage simulation system considering seawater intrusion influence according to claim 1, characterized by, The driving assembly comprises a winch and a pull rope wound on the winch; the pull rope is fixed with the first container, and the pull rope is wound or unwound by the winch to drive the first container to move relatively in the vertical direction with respect to the reflux pipe.

5. The river-groundwater seepage simulation system considering seawater intrusion influence according to claim 1, characterized by, The mixing chamber has a cylindrical structure, and the mixing chamber is provided with a spiral blade extending in the axial direction of the mixing chamber; and / or the output port of the mixing chamber is provided with a flow slowing component for slowing down the flow speed of the liquid flowing out of the output port of the mixing chamber.

6. The river-groundwater seepage simulation system considering seawater intrusion influence according to claim 1, characterized by, A one-way valve is arranged between the output port of the mixing chamber and the saltwater chamber, and the one-way valve is configured to allow the saltwater output by the output port of the mixing chamber to flow into the saltwater chamber in one direction.

7. The river-groundwater seepage simulation system considering seawater intrusion influence according to claim 1, characterized by, The output port of the mixing chamber is provided with a first sensor capable of detecting salinity; and / or the seepage area is provided with a plurality of second sensors capable of detecting salinity. The first water supply mechanism comprises a first water tank for storing freshwater with the first color and a second pump for pumping the freshwater in the first water tank into the freshwater chamber; and / or the second water supply mechanism comprises a second water tank for storing freshwater and a third pump for pumping the freshwater in the second water tank into the mixing chamber.

8. The river-groundwater seepage simulation system considering seawater backflow influence according to claim 2, characterized by, The seepage medium of the seepage area is embedded with a pre-embedded pipe for introducing pollutants; or, the second water supply mechanism comprises a second water tank for storing fresh water and a third pump for pumping the fresh water in the second water tank into the mixing chamber, and the salt water tank or the second water tank is mixed with pollutants having a third color; the third color is different from the first color and the second color.

9. The river-groundwater seepage simulation system considering seawater backflow influence according to claim 1, characterized by, Overflow ports are arranged on the salt water chamber and the fresh water chamber.

10. A river-groundwater seepage simulation method considering the influence of seawater backflow, characterized by, The method is performed by using the river-groundwater seepage simulation system considering the influence of seawater backflow as claimed in any one of claims 1-9; and the method comprises the following steps: S1, pre-saturation: start the first water supply mechanism to continuously introduce fresh water having a first color into the fresh water chamber; S2, after the first water supply mechanism works for a period of time, start the tide generating device to introduce salt water having a second color into the mixing chamber, start the second water supply mechanism to introduce fresh water into the mixing chamber, and after the salt water and the fresh water introduced into the mixing chamber are mixed in the mixing chamber, the mixed water is input into the salt water chamber through the output port of the mixing chamber; S3, real-time shooting of the picture displayed by the observation side wall of the observation tank by using a camera.

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