CN210091526U

CN210091526U - Indoor simulation device for seawater invasion

Info

Publication number: CN210091526U
Application number: CN201920327224.1U
Authority: CN
Inventors: 蒋岩; 彭犇; 田玮; 吴晓辉; 牟东阳; 程暘; 贾晋炜; 朱法强
Original assignee: Central Research Institute of Building and Construction Co Ltd MCC Group; MCC Energy Saving and Environmental Protection Co Ltd
Current assignee: Central Research Institute of Building and Construction Co Ltd MCC Group; MCC Energy Saving and Environmental Protection Co Ltd
Priority date: 2019-03-14
Filing date: 2019-03-14
Publication date: 2020-02-18
Anticipated expiration: 2029-03-14

Abstract

The utility model provides an indoor analogue means of sea water invasion, including coastal aquifer analogue means, groundwater exploitation analogue means and normal water recharge analogue means. The coastal aquifer simulation device at least comprises an acrylic box body, a lifting screw, an overflow box, a fresh water tank, a seawater tank, a water pump and an iron frame; the underground water exploitation simulating device at least comprises an acrylic pipe, a water pump and a water tank; the reclaimed water recharging simulation device at least comprises a copper valve, a water pump, a water tank and a stainless steel frame. The position of the fresh water overflow box can be controlled by controlling the lifting screw rod, and then the initial water heads of the fresh water and the seawater in the simulated aquifer are adjusted. The device can accurately reflect the influence of the underground water lifting process on seawater invasion under different hydrodynamic conditions, and experimental results can provide a data basis for establishing a seawater invasion model.

Description

Indoor simulation device for seawater invasion

Technical Field

The utility model relates to an indoor analogue means for sea water invasion.

Background

Under natural conditions, most fresh groundwater is discharged into the ocean in surface runoff or subsurface runoff. In coastal aquifers, an obvious transition zone is formed between the salt water and the fresh water under the action of hydrodynamic dispersion, and the dynamic balance between the salt water and the fresh water generally causes the transition zone to be always kept in a relatively stable position. However, after the underground water is mined out over standard, the seepage effect of the fresh water to the seawater is gradually weakened or even disappears, so that the salinity in the fresh water is gradually increased, and finally a series of ecological and environmental problems, such as water quality deterioration, land salinization and the like, are caused.

The core problems of seawater intrusion research mainly include the shape research of a salt water and fresh water interface, the motion rule research of a seawater wedge and the like. At present, most scholars at home and abroad adopt a numerical calculation method to construct a model of seawater invasion, but due to complex and various factors, most models are difficult to accurately restore hydrogeological parameters and hydrodynamic parameters of actual aquifers, and the process is complicated, so that the accuracy of a calculation result is difficult to ensure; the field observation method is also limited by various human and natural factors. Therefore, it is important to find an indoor experimental method for seawater intrusion.

SUMMERY OF THE UTILITY MODEL

The utility model provides an indoor analogue means for sea water invasion can be accurate under the reflection at different hydrodynamic force conditions, and the influence that the groundwater lift in-process caused the sea water invasion, and the experimental result can provide the data basis for the model establishment of sea water invasion.

The utility model relates to an indoor simulation device for seawater intrusion, which comprises a coastal aquifer simulation device, a groundwater mining simulation device and a reclaimed water recharge simulation device; the coastal aquifer simulation device comprises a cuboid box body (1), a base, a fresh water overflow chamber (5), a seawater overflow chamber (15), a first lifting screw (6), a second lifting screw (16), a first water tank (8), a fresh water tank (13), a second water tank (19) and a seawater tank (25); the box body (1) is arranged on the base, and the inside of the box body (1) is divided into a fresh water supply chamber (2), a seawater supply chamber (3) and a sand filling area by a separating device; the left side of the box body (1) is provided with a fresh water supply chamber (2), the right side of the box body is provided with a seawater supply chamber (3), and the sand filling area is positioned between the fresh water supply chamber (2) and the seawater supply chamber (3); the first lifting screw (6) and the second lifting screw (16) are respectively positioned at the left side and the right side of the box body (1) and are arranged on the base; the fresh water overflow chamber (5) is arranged on the first lifting screw (6) and the height is changed by the rotation of the first lifting screw (6), and the seawater overflow chamber (15) is arranged on the second lifting screw (16) and the height is changed by the rotation of the second lifting screw (6); the fresh water overflow chamber (5) is communicated with the fresh water supply chamber (2) through a first communicating pipe (9) and is used for supplying fresh water into the fresh water supply chamber (2) so as to simulate underground water in a coastal aquifer; the seawater overflow chamber (15) is communicated with the seawater supply chamber (3) through a second communicating pipe (20) and is used for supplying simulated seawater into the seawater supply chamber (3) so as to simulate seawater in a coastal aquifer; the underground water exploitation simulating device comprises a pipe body (27) and a water pumping device, wherein the pipe body (27) is fixed in a sand filling area of the box body (1), and the bottom of the pipe body is located at the bottom of the box body (1) and is connected with the water pumping device to simulate complete well water pumping; the reclaimed water recharge simulating device is fixed above the box body (1) and used for supplementing water into the box body (1) and simulating reclaimed water recharge.

Wherein, the fresh water overflow chamber (5) is provided with an overflow port, is positioned in the middle of the fresh water overflow chamber (5), and is connected with the first water tank (8) through a first overflow pipe (7); the fresh water overflow chamber (5) is connected with a first water suction pump (11) through a fresh water outlet pipe (10), the first water suction pump (11) is connected with a fresh water tank (13) through a fresh water inlet pipe (12), tap water is filled in the fresh water tank (13) and used for simulating fresh water, and the tap water in the fresh water tank (13) is pumped into the fresh water overflow chamber (5) from the fresh water tank (13) through the first water suction pump (11).

Wherein, the seawater overflow chamber (15) is provided with an overflow port, is positioned in the middle of the seawater overflow chamber (15), and is connected with a second water tank (19) through a second overflow pipe (17); the seawater overflow chamber (15) is connected with a second water suction pump (23) through a seawater outlet pipe (22), the second water suction pump (23) is connected with a seawater tank (25) through a seawater inlet pipe (24), simulated seawater is filled in the seawater tank (25), and the simulated seawater is pumped into the seawater overflow chamber (15) from the seawater tank (25) through the second water suction pump (23).

The box body is a transparent acrylic box body (1), and scale paper is adhered to the surface of the box body; the underground water mining simulation device also comprises a third water tank (31), the pipe body (27) is a transparent acrylic pipe, and the water pumping device comprises a third water pump (29), a first water pumping pipe (28) and a second water draining pipe (30); a plurality of small holes are drilled at the lower part of the column body of the acrylic tube, and a screen is arranged in the small holes; the bottom of the column body is connected with one side of a joint, the other side of the joint is connected with one end of a third water suction pump (29) through a first water suction pipe (28), and the other end of the third water suction pump (29) is connected with a third water tank (31) through a second water discharge pipe (30) so as to simulate the water suction of a complete well.

Wherein, the bottom of the seawater supply chamber (3) is provided with a first valve (21) which is connected with a second water tank (19) through a first drain pipe (18) and used for discharging redundant fresh water in the water saturation process.

The reclaimed water recharging simulation device comprises a stainless steel frame (32), a plurality of water conveying pipes (34), a fourth water pump (35), a second water pumping pipe (36) and a fourth water tank (37); the reclaimed water recharging simulation device is fixed above the box body (1) through a stainless steel frame (32), the stainless steel frame (32) is provided with a plurality of water pipes (34), one end of each water pipe (34) is provided with a plurality of second valves (33), and the other end of each water pipe is connected with a fourth water pump (35); the fourth water pump (35) pumps tap water in the fourth water tank (37) through the second water pumping pipe (36) and replenishes the tap water into the box body (1) through a plurality of water conveying pipes (34) so as to simulate reclaimed water recharging.

The first and second manual turntables (4, 14) are arranged on the tops of the first and second lifting screws (6, 16) and are used for driving the first and second lifting screws (6, 16) to rotate, so that the fresh water overflow chamber (5) and the seawater overflow chamber (15) change heights.

The utility model discloses still relate to a method that uses the indoor analogue means of sea water invasion to simulate, prefer indoor analogue means be according to the preceding indoor analogue means of sea water invasion, include following step:

step (1), sand filling: filling quartz sand into a sand filling area in the box body (1) to simulate the water-containing medium of a coastal water-containing layer before the simulation begins; preferably, about 5cm of quartz sand is filled each time in the sand filling process, an organic glass plate is used for paving, external force applied to the quartz sand is reduced as much as possible, the water-containing layer keeps isotropy, and the process is repeated until the sand is filled to 80 cm;

step (2), water saturation: the fresh water overflow chamber (5) and the seawater overflow chamber (15) are adjusted to the required height by utilizing a first lifting screw (6) and a second lifting screw (16), and a water stop clamp is used for closing a seawater outlet pipe (22); filling tap water into a fresh water tank (13), pumping the tap water filled into the fresh water tank (13) into a fresh water overflow chamber (5) by using a first water suction pump (11), then sending the tap water into a fresh water supply chamber (2) through a first communicating pipe (9), and saturating the filled quartz sand; after the water level in the box body (1) is not fluctuated, the first water pump (11) is closed, a water stop clamp on the seawater outlet pipe (22) is removed, and the fresh water in the seawater overflow chamber (15) is quickly drained;

step (3) first stage of experiment: opening a first valve (21), discharging the fresh water in the seawater supply chamber (3) into a second water tank (19) through a first water discharge pipe (18), and discharging the fresh water in the seawater supply chamber (3) completely to discharge redundant fresh water in the water saturation process; simultaneously, filling tap water added with sea salt and pigment into a seawater tank (25) for forming simulated seawater, wherein the pigment is preferably red pigment; after the fresh water is drained, closing the first valve (21), pumping the simulated seawater filled in the seawater tank (25) into the seawater overflow chamber (15) by using a second water pump (23), then sending the simulated seawater into the seawater supply chamber (3) through a second communicating pipe (20), slowly injecting the seawater in the seawater overflow chamber (15) into the seawater supply chamber (3), and stopping adding water after reaching a specified water level; opening the first water pump (11) and the second water pump (23), and observing and recording the transport condition of the simulated seawater in the box body (1) and the shape of the interface of the seawater and the fresh water;

step (4) second stage of experiment: opening a third water pump (29), simulating the pumping of the whole well, wherein the initial flow rate of the third water pump is set to be consistent with that of the first water pump (11), then gradually increasing the pumping amount of the third water pump (29), and observing and recording the migration condition of the simulated seawater in the box body (1) and the shape of a seawater-fresh water interface in the flow rate change process;

step (5) experimental third stage: when the foremost end of the simulated seawater diffuses through the midpoint of the box body (1), opening a fourth water suction pump (35) and a second valve (33), setting the initial flow rate of the simulated seawater to be consistent with that of the first water suction pump (11), and gradually increasing the current water suction amount of a third water suction pump (29); observing and recording the migration condition of seawater in the box body and the shape of the interface between seawater and fresh water in the flow change process

Realize the utility model discloses the technical scheme that above-mentioned purpose adopted does:

an indoor simulation device for seawater intrusion at least comprises a coastal aquifer simulation device, an underground water exploitation simulation device and a reclaimed water recharge simulation device.

The coastal aquifer simulation device consists of a transparent acrylic box body, a lifting screw, an overflow box, a fresh water tank, a seawater tank, a water pump and a base. The box body is 160cm long, 50cm wide, 100cm high, the bottom plate is 20mm thick, and the periphery is 15mm thick. The surface of the box body is pasted with scale paper, and the scale paper is sequentially increased from left to right and from bottom to top. The box body is divided into 3 parts by the screen and the partition board, the left part and the right part are respectively a fresh water supply chamber and a seawater supply chamber, the two water supply chambers are 5cm long, and the width and the height of the two water supply chambers are consistent with those of the box body. The box body is fixed on an iron stand, and the iron stand is 200cm long, 60cm wide and 50cm high. Both sides of the iron frame are respectively provided with a lifting screw. The screw is provided with an overflow box with the length of 10cm, the width of 10cm and the height of 15cm, and the height of the overflow box can be changed along with the screw (for example, a worm wheel and worm structure is adopted). The overflow port is located the overflow case middle part, links to each other with outside basin through the overflow pipe. Two copper joints with the diameter of 3cm are arranged at the bottom of the overflow box and are respectively connected with the fresh (salt) water supply chamber and the bottom water pump. The bottom of the seawater supply chamber is provided with a direct 3cm copper valve which is connected with the water tank through a water outlet pipe.

The underground water exploitation simulator consists of a transparent acrylic pipe, a water pump and a water tank. The acrylic tube is fixed at the position of 30cm of the box body, the diameter of the acrylic tube is 3cm, and the height of the acrylic tube is consistent with that of the box body. The lower part of the column body is drilled with a plurality of small holes with the diameter of about 2mm, and the inside of the small holes is provided with a screen. The bottom of the column body is provided with a copper joint with the same diameter, and the other side of the joint is connected with a water pump to simulate the pumping of a complete well.

The reclaimed water recharging simulation device is composed of a copper valve, a water pump, a water tank and a stainless steel frame. The stainless steel frame is 170cm long, 50cm wide and 10cm high and can be fixed above the box body. A plurality of water pipes are arranged on the stainless steel frame near the seawater and provided with copper valves, and the other sides of the water pipes are connected with a water pump.

Compared with the prior art, the utility model provides an indoor analogue means of sea water invasion has following advantage: 1. the fresh water supply chamber and the seawater supply chamber can prevent the water pump from directly injecting test water into the simulated aquifer to damage the filled sand sample. 2. The fresh water overflow chamber and the seawater overflow chamber can regulate and control the water levels in the fresh water supply chamber and the seawater supply chamber, provide a stable constant head boundary condition for experiments, and can simulate the influence of different hydrodynamic conditions on seawater intrusion. 3. The water pump in the underground water exploitation simulating device can be used for manually regulating and controlling the flow, and is beneficial to exploring the influence of different underground water exploitation strengths on seawater invasion. 4. Because the reclaimed water recharge simulating device is arranged, the influence of reclaimed water recharge on seawater invasion and the relation between reclaimed water recharge quantity and underground water exploitation quantity can be explored. The position of the fresh water overflow box can be controlled by controlling the lifting screw rod, and then the initial water heads of the fresh water and the seawater in the simulated aquifer are adjusted. The device can accurately reflect the influence of the underground water lifting process on seawater invasion under different hydrodynamic conditions, and experimental results can provide a data basis for establishing a seawater invasion model.

Drawings

Fig. 1 is the overall structure schematic diagram of the indoor simulation device for seawater intrusion provided by the present invention.

1-acrylic box body, 2-fresh water supply chamber, 3-seawater supply chamber, 4-first manual rotating disc, 5-fresh water overflow chamber, 6-first liftable screw, 7-first overflow pipe, 8-first water tank, 9-first communicating pipe, 10-fresh water outlet pipe, 11-first water pump, 12-fresh water inlet pipe, 13-fresh water tank, 14-second manual rotating disc, 15-seawater overflow chamber, 16-second liftable screw, 17-second overflow pipe, 18-first water outlet pipe, 19-second water tank, 20-second communicating pipe, 21-first valve, 22-seawater outlet pipe, 23-second water pump, 24-seawater inlet pipe, 25-seawater tank, 26-iron frame, 27-acrylic column, 28-first water suction pipe, 29-third water suction pump, 30-second water discharge pipe, 31-third water tank, 32-stainless steel frame, 33-second valve, 34-water delivery pipe, 35-fourth water suction pump, 36-second water suction pipe and 37-fourth water tank.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, an indoor simulation apparatus for seawater intrusion includes a coastal aquifer simulation apparatus, a groundwater mining simulation apparatus, and a reclaimed water recharge simulation apparatus; the coastal aquifer simulation device comprises a box body 1, a base (an iron frame 26), a fresh water overflow chamber 5, a seawater overflow chamber 15, a first lifting screw 6, a second lifting screw 16, a first water tank 8, a fresh water tank 13, a second water tank 19 and a seawater tank 25; the box body 1 is arranged on the base, and the inside of the box body 1 is divided into a fresh water supply chamber 2, a seawater supply chamber 3 and a sand filling area by a separating device; the left side of the box body 1 is provided with a fresh water supply chamber 2, the right side of the box body is provided with a seawater supply chamber 3, and the sand filling area is positioned between the fresh water supply chamber 2 and the seawater supply chamber 3; the first lifting screw 6 and the second lifting screw 16 are respectively positioned at the left side and the right side of the box body 1 and are arranged on the base; the fresh water overflow chamber 5 is installed on the first liftable screw 6 and the height is changed by the rotation of the first liftable screw 6, and the seawater overflow chamber 15 is installed on the second liftable screw 16 and the height is changed by the rotation of the second liftable screw 6; the fresh water overflow chamber 5 is communicated with the fresh water supply chamber 2 through a first communication pipe 9 and is used for supplying fresh water into the fresh water supply chamber 2 so as to simulate underground water in a coastal aquifer; the seawater overflow chamber 15 is communicated with the seawater supply chamber 3 through a second communicating pipe 20 and is used for supplying simulated seawater into the seawater supply chamber 3 so as to simulate seawater in a coastal aquifer; the underground water exploitation simulating device comprises a pipe body 27 and a water pumping device, wherein the pipe body 27 is fixed in a sand filling area of the box body 1, and the bottom of the pipe body is positioned at the bottom of the box body 1 and is used for being connected with the water pumping device and simulating complete well water pumping; the reclaimed water recharge simulating device is fixed above the box body 1 and used for supplementing water into the box body 1 and simulating reclaimed water recharge.

Wherein, the fresh water overflow chamber 5 is provided with an overflow port, is positioned in the middle of the fresh water overflow chamber 5 and is connected with the first water tank 8 through the first overflow pipe 7; the fresh water overflow chamber 5 is connected with a first water suction pump 11 through a fresh water outlet pipe 10, the first water suction pump 11 is connected with a fresh water tank 13 through a fresh water inlet pipe 12, tap water is contained in the fresh water tank 13 and used for simulating fresh water, and the tap water in the fresh water tank 13 is pumped into the fresh water overflow chamber 5 from the fresh water tank 13 through the first water suction pump 11. The seawater overflow chamber 15 is provided with an overflow port, is positioned in the middle of the seawater overflow chamber 15, and is connected with a second water tank 19 through a second overflow pipe 17; the seawater overflow chamber 15 is connected with a second water pump 23 through a seawater outlet pipe 22, the second water pump 23 is connected with a seawater tank 25 through a seawater inlet pipe 24, simulated seawater is filled in the seawater tank 25, and the simulated seawater is pumped into the seawater overflow chamber 15 from the seawater tank 25 through the second water pump 23. The box body is a transparent acrylic box body 1, and scale paper is adhered to the surface of the box body; the underground water mining simulation device further comprises a third water tank 31, the pipe body 27 is a transparent acrylic pipe, and the water pumping device comprises a third water pump 29, a first water pumping pipe 28 and a second water draining pipe 30; a plurality of small holes are drilled at the lower part of the column body of the acrylic tube, and a screen is arranged in the small holes; the bottom of the column is connected with one side of a joint, the other side of the joint is connected with one end of a third water pump 29 through a first water pumping pipe 28, and the other end of the third water pump 29 is connected with a third water tank 31 through a second water drainage pipe 30 so as to simulate the water pumping of a complete well. The bottom of the seawater supply chamber 3 is provided with a first valve 21, and is connected with a second water tank 19 through a first water discharge pipe 18 for discharging excessive fresh water in the water saturation process. The reclaimed water recharging simulation device comprises a stainless steel frame 32, a plurality of water conveying pipes 34, a fourth water suction pump 35, a second water suction pipe 36 and a fourth water tank 37; the reclaimed water recharging simulation device is fixed above the box body 1 through a stainless steel frame 32, the stainless steel frame 32 is provided with a plurality of water pipes 34, one end of each water pipe 34 is provided with a plurality of second valves 33, and the other end of each water pipe is connected with a fourth water pump 35; the fourth water pump 35 pumps tap water in a fourth water tank 37 through a second water pumping pipe 36 and replenishes the tap water into the tank 1 through a plurality of water conveying pipes 34 to simulate reclaimed water recharging. The first and second manual rotating discs 4, 14 are installed on the top of the first and second

liftable screws

6, 16 for driving the first and second

liftable screws

6, 16 to rotate, thereby making the fresh water overflow chamber 5 and the seawater overflow chamber 15 change height.

As shown in fig. 1, a method for simulating using an indoor simulator for seawater intrusion, preferably an indoor simulator for seawater intrusion according to the foregoing description, comprises the steps of:

step (1), sand filling: filling quartz sand into a sand filling area in the box body 1 to simulate the water-containing medium of a coastal water-containing layer before the simulation begins; preferably, about 5cm of quartz sand is filled each time in the sand filling process, an organic glass plate is used for paving, external force applied to the quartz sand is reduced as much as possible, the water-containing layer keeps isotropy, and the process is repeated until the sand is filled to 80 cm;

step (2), water saturation: the fresh water overflow chamber 5 and the seawater overflow chamber 15 are adjusted to the required height by using the first lifting screw 6 and the second lifting screw 16, and the seawater outlet pipe 22 is closed by using a water stop clamp; filling tap water into a fresh water tank 13, pumping the tap water filled into the fresh water tank 13 into a fresh water overflow chamber 5 by using a first water suction pump 11, and then sending the tap water into a fresh water supply chamber 2 through a first communication pipe 9 to saturate the filled quartz sand with water; after the water level in the box body 1 is not fluctuated, the first water pump 11 is closed, the water stop clamp on the seawater outlet pipe 22 is removed, and the fresh water in the seawater overflow chamber 15 is quickly drained; step (3) first stage of experiment: opening the first valve 21, discharging the fresh water in the seawater supply chamber 3 to the second water tank 19 through the first water discharge pipe 18, and discharging the fresh water in the seawater supply chamber 3 to be clean so as to discharge the redundant fresh water in the water saturation process; simultaneously, filling tap water added with sea salt and pigment into a seawater tank 25 for forming simulated seawater, wherein the pigment is preferably red pigment; after the fresh water is drained, closing the first valve 21, pumping the simulated seawater filled in the seawater tank 25 into the seawater overflow chamber 15 by using the second water pump 23, then sending the seawater into the seawater supply chamber 3 through the second communicating pipe 20, slowly injecting the seawater in the seawater overflow chamber 15 into the seawater supply chamber 3, and stopping adding the water after the seawater reaches a specified water level; opening the first water pump 11 and the second water pump 23, and observing and recording the transport condition of the simulated seawater in the box body 1 and the shape of the interface of the seawater and the fresh water;

step (4) second stage of experiment: the third water pump 29 is opened to simulate the pumping of the whole well, the initial flow setting of the third water pump is consistent with that of the first water pump 11, then the pumping amount of the third water pump 29 is gradually increased, and the migration condition of the simulated seawater in the box body 1 and the shape of the interface of the seawater and the fresh water in the flow change process are observed and recorded;

step (5) experimental third stage: when the foremost end of the simulated seawater diffuses through the midpoint of the box body 1, opening the fourth water pump 35 and the second valve 33, setting the initial flow rate of the simulated seawater to be consistent with that of the first water pump 11, and gradually increasing the current water pumping amount of the third water pump 29; observing and recording the migration condition of seawater in the box body and the shape of the interface between seawater and fresh water in the flow change process

Further, as shown in fig. 1, the main body of the device is an acrylic box 1, and the surface of the device is adhered with scale paper, which is fixed on an iron frame 26 (base) through screws. The inside 3 parts of being divided into by the baffle of ya keli box 1, fresh water supply chamber 2, sea water supply chamber 3 and the district of filling sand. In addition, an acrylic column 27 is fixed in the sand filling area (30cm scale), a copper joint is installed on a box body at the bottom of the acrylic column 27 and is connected with a third water suction pump 29 through a first water suction pipe 28, and the other side of the third water suction pump 29 is connected with a third water tank 31 through a second water discharge pipe 30 to simulate water suction of a complete well. The iron frame 26 is provided with a first lifting screw 6 and a second lifting screw 16. The first lifting screw 6 is provided with a fresh water overflow chamber 5, and the height of the fresh water overflow chamber 5 can be adjusted through the first manual rotating disc 4. In addition, the fresh water overflow chamber 5 is connected with the fresh water supply chamber 2 through a first communication pipe 9, and is connected with a first water pump 11 through a fresh water outlet pipe 10. The first water pump 11 is connected with the fresh water tank 13 through the fresh water inlet pipe 12 and supplies fresh water into the acrylic tank body 1 to simulate underground water in a coastal aquifer. The second lifting screw 16 is provided with a seawater overflow chamber 15, and the height of the seawater overflow chamber 15 can be adjusted through the second manual rotating disc 14. The overflow gap of the seawater overflow chamber 5 is located at the right side, and the excessive seawater in the experiment process can flow out through the overflow gap and flow into the second water tank 19 through the second overflow pipe 17. The bottom of the seawater overflow chamber 15 is connected with the seawater supply chamber 3 through a second communicating pipe 20, and is connected with a second water pump 23 at the bottom through a seawater outlet pipe 22. The second suction pump 23 is connected to a seawater tank 25 through a seawater inlet pipe 24, and supplies seawater into the acryl tank 1 to simulate seawater. In addition, a first valve 21 is installed at the bottom of the seawater supply chamber 3 and connected with a second water tank 19 through a first water discharge pipe 18 for discharging excess fresh water during the water saturation process. The stainless steel frame 32 can be fixed above the acrylic box body 1 through screws, a plurality of water pipes 34 are placed on the frame, one end of each water pipe is provided with a plurality of second valves 33, and the other end of each water pipe is connected with a fourth water pump 35. The fourth water pump 35 can pump tap water in the fourth water tank 37 through the second water pumping pipe 36 and replenish the tap water into the acrylic tank 1 to simulate reclaimed water recharging.

The utility model provides a device application method as follows:

1. sand filling: before the experiment is started, the water-containing medium (excluding a fresh water supply chamber, a seawater supply chamber and an acrylic column) of a coastal aquifer simulated by quartz sand is filled in the acrylic box body 1. Filling 5cm of quartz sand each time during the sand filling process, paving the quartz sand by using an organic glass plate, reducing external force applied to the quartz sand as much as possible to keep the water-containing layer isotropic, and repeating the process until the sand is filled to 80 cm.

2. Water saturation: the devices on the side of the fresh water supply chamber 2 are connected as described above. The fresh water overflow chamber 5 and the seawater overflow chamber 15 are adjusted to a desired height by the first lifting screw 6 and the second lifting screw 16, and the seawater outlet pipe 22 is closed by the water stop clip. Tap water is filled into the fresh water tank 13, and the filled sand sample is saturated with water by using the first water pump 11. And after the water level in the tank body does not fluctuate obviously, closing the first water pump 11. The water stop clamp on the seawater outlet pipe 22 is removed, and the fresh water in the seawater overflow chamber 15 is quickly drained.

3. The first stage of the experiment, the apparatus on the seawater feed chamber 3 side was connected as described above. The first valve 21 is opened to drain the fresh water in the seawater supply chamber 3, and the seawater tank 19 is filled with tap water to which sea salt and red pigment are added. After the fresh water is drained, the first valve 21 is closed, the seawater in the seawater tank 19 is slowly filled into the seawater supply chamber 3, and the water is stopped from being added after the seawater reaches a specified water level. And (3) opening the first water pump 11 and the second water pump 23, and observing and recording the migration condition of the seawater in the box body and the shape of the interface of the seawater and the fresh water.

4. Experiment second stage: and (3) starting the third water pump 29 to simulate the whole well to pump water, wherein the initial flow setting is consistent with that of the first water pump 11, then gradually increasing the water pumping amount of the third water pump 29, and observing and recording the migration condition of the seawater in the box body and the shape of the interface of the seawater and the fresh water in the flow change process.

5. And (3) experimental third stage: when the foremost end of the seawater diffuses through the middle point of the tank body, the fourth water pump 35 and the second valve 33 are opened, the initial flow rate setting of the fourth water pump is consistent with that of the first water pump 11, and then the current water pumping amount of the third water pump 29 is gradually increased. And observing and recording the migration condition of the seawater in the box body and the shape of the interface of the seawater and the fresh water in the flow change process.

Claims

1. An indoor simulation device for seawater intrusion is characterized by comprising a coastal aquifer simulation device, a groundwater exploitation simulation device and a reclaimed water recharge simulation device; the coastal aquifer simulation device comprises a cuboid box body (1), a base, a fresh water overflow chamber (5), a seawater overflow chamber (15), a first lifting screw (6), a second lifting screw (16), a first water tank (8), a fresh water tank (13), a second water tank (19) and a seawater tank (25); the box body (1) is arranged on the base, and the inside of the box body (1) is divided into a fresh water supply chamber (2), a seawater supply chamber (3) and a sand filling area by a separating device; the left side of the box body (1) is provided with a fresh water supply chamber (2), the right side of the box body is provided with a seawater supply chamber (3), and the sand filling area is positioned between the fresh water supply chamber (2) and the seawater supply chamber (3); the first lifting screw (6) and the second lifting screw (16) are respectively positioned at the left side and the right side of the box body (1) and are arranged on the base; the fresh water overflow chamber (5) is arranged on the first lifting screw (6) and the height is changed by the rotation of the first lifting screw (6), and the seawater overflow chamber (15) is arranged on the second lifting screw (16) and the height is changed by the rotation of the second lifting screw (16); the fresh water overflow chamber (5) is communicated with the fresh water supply chamber (2) through a first communicating pipe (9) and is used for supplying fresh water into the fresh water supply chamber (2) so as to simulate underground water in a coastal aquifer; the seawater overflow chamber (15) is communicated with the seawater supply chamber (3) through a second communicating pipe (20) and is used for supplying simulated seawater into the seawater supply chamber (3) so as to simulate seawater in a coastal aquifer; the underground water exploitation simulating device comprises a pipe body (27) and a water pumping device, wherein the pipe body (27) is fixed in a sand filling area of the box body (1), and the bottom of the pipe body is located at the bottom of the box body (1) and is connected with the water pumping device to simulate complete well water pumping; the reclaimed water recharge simulating device is fixed above the box body (1) and used for supplementing water into the box body (1) and simulating reclaimed water recharge.

2. An indoor seawater intrusion simulation device according to claim 1, wherein the fresh water overflow chamber (5) has an overflow port, which is located in the middle of the fresh water overflow chamber (5) and is connected to the first water tank (8) through a first overflow pipe (7); the fresh water overflow chamber (5) is connected with a first water suction pump (11) through a fresh water outlet pipe (10), the first water suction pump (11) is connected with a fresh water tank (13) through a fresh water inlet pipe (12), tap water is filled in the fresh water tank (13) and used for simulating fresh water, and the tap water in the fresh water tank (13) is pumped into the fresh water overflow chamber (5) from the fresh water tank (13) through the first water suction pump (11).

3. An indoor seawater intrusion simulation device according to claim 1 or 2, wherein the seawater spillway chamber (15) has an overflow outlet, which is located in the middle of the seawater spillway chamber (15) and is connected to the second water tank (19) through a second overflow pipe (17); the seawater overflow chamber (15) is connected with a second water suction pump (23) through a seawater outlet pipe (22), the second water suction pump (23) is connected with a seawater tank (25) through a seawater inlet pipe (24), simulated seawater is filled in the seawater tank (25), and the simulated seawater is pumped into the seawater overflow chamber (15) from the seawater tank (25) through the second water suction pump (23).

4. The indoor simulation device for seawater intrusion according to claim 1 or 2, wherein the box body is a transparent acrylic box body, and scale paper is adhered to the surface of the box body; the underground water mining simulation device also comprises a third water tank (31), the pipe body (27) is a transparent acrylic pipe, and the water pumping device comprises a third water pump (29), a first water pumping pipe (28) and a second water draining pipe (30); a plurality of small holes are drilled at the lower part of the column body of the acrylic tube, and a screen is arranged in the small holes; the bottom of the column body is connected with one side of a joint, the other side of the joint is connected with one end of a third water suction pump (29) through a first water suction pipe (28), and the other end of the third water suction pump (29) is connected with a third water tank (31) through a second water discharge pipe (30) so as to simulate the water suction of a complete well.

5. An indoor seawater intrusion simulation system according to claim 1 or 2, wherein the seawater supply chamber (3) is provided at its bottom with a first valve (21) and connected to the second tank (19) via a first drain pipe (18) for draining excess fresh water during the saturation process.

6. An indoor simulation device for seawater intrusion according to claim 1 or 2, wherein the simulation device for reclaimed water recharge comprises a stainless steel frame (32), a plurality of water pipes (34), a fourth water pump (35), a second water pumping pipe (36) and a fourth water tank (37); the reclaimed water recharging simulation device is fixed above the box body (1) through a stainless steel frame (32), the stainless steel frame (32) is provided with a plurality of water pipes (34), one end of each water pipe (34) is provided with a plurality of second valves (33), and the other end of each water pipe is connected with a fourth water pump (35); the fourth water pump (35) pumps tap water in the fourth water tank (37) through the second water pumping pipe (36) and replenishes the tap water into the box body (1) through a plurality of water conveying pipes (34) so as to simulate reclaimed water recharging.

7. An indoor seawater intrusion simulation apparatus according to claim 1 or 2, wherein the first and second manual rotation discs (4, 14) are installed on top of the first and second liftable screws (6, 16) for driving the first and second liftable screws (6, 16) to rotate, thereby allowing the fresh water overflow chamber (5) and the seawater overflow chamber (15) to change heights.