CN211668742U - Experimental device for be used for studying physical barrier of control sea water invasion - Google Patents
Experimental device for be used for studying physical barrier of control sea water invasion Download PDFInfo
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Abstract
The utility model provides an experimental apparatus for be used for studying physical barrier of control seawater invasion, it includes: the system comprises a water flowing tank for simulating a coastal aquifer, a first water tank for loading fresh water and a second water tank for loading seawater; porous media are arranged in the launder, the launder is clamped between the first water tank and the second water tank, and the launder is respectively communicated with the first water tank and the second water tank. By designing the experimental device for researching the physical barrier for controlling seawater intrusion, the situation that the barrier system controls seawater intrusion is simulated, so that a user can visually learn the process of controlling seawater intrusion by the barrier system, the on-site investigation is not needed, the labor intensity of the user is reduced, and the user can conveniently understand the process of controlling seawater intrusion by the barrier system.
Description
Technical Field
The utility model relates to a sea water invasion experiment technical field especially relates to an experimental apparatus for be used for studying physical barrier of control sea water invasion.
Background
The construction of underground physical barriers is one of the methods for controlling the invasion of coastal aquifer seawater. Therefore, the hybrid physical barrier is provided as a novel seawater intrusion control barrier system and consists of a waterproof water-stop wall and a semi-permeable underground interception dam. When the barrier system is put into use, the working performance of the barrier system needs to be analyzed in depth.
In the prior art, users can only carry out on-site investigation usually to obtain the condition of the barrier system for controlling seawater intrusion, and the users have higher labor intensity and can not visually learn the process of the barrier system for controlling seawater intrusion.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that to prior art not enough, provide an experimental apparatus for studying the physics protective screen of control sea water invasion.
The utility model provides an above-mentioned technical problem's technical scheme as follows: an experimental apparatus for investigating a physical barrier controlling seawater ingress, comprising: the system comprises a water flowing tank for simulating a coastal aquifer, a first water tank for loading fresh water and a second water tank for loading seawater; porous media are arranged in the launder, the launder is clamped between the first water tank and the second water tank, and the launder is respectively communicated with the first water tank and the second water tank.
The utility model has the advantages that: the experimental device for researching the physical barrier for controlling seawater intrusion simulates the situation that the barrier system controls seawater intrusion, so that a user can visually learn the process of controlling seawater intrusion by the barrier system, on-site investigation is not needed, the labor intensity of the user is reduced, and the user can conveniently understand the process of controlling seawater intrusion by the barrier system.
Further, still include: a pair of screens for blocking porous media, the pair of screens being respectively and correspondingly disposed at a communication position between the gutter channel and the first water tank and a communication position between the gutter channel and the second water tank.
The beneficial effect of adopting the further scheme is that: due to the arrangement of the filter screen, the porous medium is prevented from flowing out of the launder, the reliability of the experimental device is improved, and the user experience is improved.
Further, the filter screen is an acrylic screen.
The beneficial effect of adopting the further scheme is that: the arrangement of the acrylic acid net prevents the porous medium from flowing out of the launder, improves the reliability of the experimental device, improves the user experience, and reduces the production cost.
Further, the porous medium is a plurality of glass beads, quartz sand or plastic beads.
The beneficial effect of adopting the further scheme is that: a plurality of glass beads are combined to form a porous medium, the accuracy of the experimental device is improved,
further, the diameter of the glass beads is 1.1 mm.
The beneficial effect of adopting the further scheme is that: the diameter of glass pearl is 1.1 millimeter, improves experimental apparatus's precision, improves experimental apparatus's reliability.
Further, still include: the device comprises a first ultrasonic sensor and a second ultrasonic sensor, wherein the first ultrasonic sensor is used for measuring the energy consumed by the fresh water in the first water tank overcoming resistance during the movement process, the second ultrasonic sensor is used for measuring the energy consumed by the seawater in the second water tank overcoming resistance during the movement process, the first ultrasonic sensor is arranged at the top of the first water tank, and the second ultrasonic sensor is arranged at the top of the second water tank.
The beneficial effect of adopting the further scheme is that: the ultrasonic sensor is used for measuring the energy consumed by liquid in the water tank in the movement process of overcoming resistance, so that the accuracy of experimental data is improved, and the fidelity of the experimental device is improved.
Further, still include: the first adjustable overflow valve is arranged in the first water tank, the input end of the first adjustable overflow valve is communicated with the inside of the first water tank, and the output end of the first adjustable overflow valve is communicated with the outside; the second adjustable overflow valve is arranged in the second water tank, the input end of the second adjustable overflow valve is communicated with the inside of the second water tank, and the output end of the second adjustable overflow valve is communicated with the outside.
The beneficial effect of adopting the further scheme is that: the setting of overflow valve with adjustable, the user of being convenient for adjusts the height of water tank water level according to actual need, is convenient for discharge the water that surpasss in the water tank and predetermine the water level outside the water tank through overflow valve with adjustable, improves the control precision of water tank water level.
Further, still include: the output end of the first adjustable overflow valve is connected with one end of the first hose, and the other end of the first hose is communicated with the outside; the output end of the second adjustable overflow valve is connected with one end of the second hose, and the other end of the second hose is communicated with the outside.
The beneficial effect of adopting the further scheme is that: the setting of hose for water to in the box carries out the drainage, the drainage of being convenient for is handled, improves user experience.
Further, the length of the launder is 0.38 meter, the height of the launder is 0.15 meter, and the width of the launder is 0.01 meter.
The beneficial effect of adopting the further scheme is that: due to the special size design of the flume, the proximity of the experimental device to the actual seawater invasion is improved, and the accuracy of the experimental result is improved.
Further, the launder further includes: the water-stop wall and the infiltration wall, the water-stop wall and the infiltration wall all set up the inside of tye, the water-stop wall and the infiltration wall is platelike structure, the infiltration wall sets up the right side of water-stop wall, the bottom of water-stop wall with there is overlap area at the top of infiltration wall, the water-stop wall with be provided with the clearance between the infiltration wall, the top of water-stop wall with the top wall connection of tye, the bottom of infiltration wall with the bottom wall connection of tye.
The beneficial effect of adopting the further scheme is that: the water-stop wall and the permeable wall are arranged and used for simulating the physical barrier, so that the accuracy of experimental data is improved, and a user can conveniently experiment the physical barrier.
Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
Fig. 1 is one of schematic structural diagrams of an experimental apparatus provided by an embodiment of the present invention.
Fig. 2 is a second schematic structural diagram of an experimental apparatus according to an embodiment of the present invention.
The reference numbers illustrate: 1-a flume; 2-a first water tank; 3-a second water tank; 4-a first ultrasonic sensor; 5-a second ultrasonic sensor; 6-a first adjustable overflow valve; 7-a second adjustable overflow valve; 8-a first hose; 9-a second hose; 10-a water-proof wall; 11-permeable walls.
Detailed Description
The principles and features of the present invention are described below in conjunction with the following drawings, the examples given are only intended to illustrate the present invention and are not intended to limit the scope of the present invention.
As shown in fig. 1 and fig. 2, fig. 1 is a schematic structural diagram of an experimental apparatus provided in an embodiment of the present invention. Fig. 2 is a second schematic structural diagram of an experimental apparatus according to an embodiment of the present invention.
The embodiment of the utility model provides an experimental apparatus for be used for studying physical barrier of control seawater invasion, it includes: a launder 1 for simulating a coastal aquifer, a first tank 2 for loading fresh water and a second tank 3 for loading seawater; porous media are arranged in the launder 1, the launder 1 is clamped between the first water tank 2 and the second water tank 3, and the launder 1 is respectively communicated with the first water tank 2 and the second water tank 3.
The utility model has the advantages that: the experimental device for researching the physical barrier for controlling seawater intrusion simulates the situation that the barrier system controls seawater intrusion, so that a user can visually learn the process of controlling seawater intrusion by the barrier system, on-site investigation is not needed, the labor intensity of the user is reduced, and the user can conveniently understand the process of controlling seawater intrusion by the barrier system.
The construction of underground physical barriers is one of the methods for controlling the invasion of coastal aquifer seawater. The embodiment of the utility model provides a Mixed Physical Barrier (MPB) is proposed as a neotype sea water intrusion control protective screen system, and it comprises impervious diaphragm wall and the secret interception dam of semi-permeable water. Firstly, the influence of the traditional physical barrier on the dynamics of the unsteady seawater wedge under different hydraulic gradient conditions is discussed, and then the working performance of the MPB is deeply analyzed. The experiment adopts a newly developed automatic image analysis method based on light concentration conversion, and the experiment is completed in a porous medium pool. The experimental data were evaluated for consistency using numerical modeling software (seacast) and the sensitivity of the barrier performance to various key parameters was investigated. The results show that MPB causes a significant increase in the flux of high density seawater towards the outlet under the action of fresh water. After the seawater ascending mechanism is observed for the first time, the invasion length of the brine is obviously shortened. Compared with the semi-permeable underground dam and the water-stop wall, the use of the MPB reduces the seawater invasion length by 62% and 42%, respectively. When the wall thickness is 40% of the hydrous layer thickness, the MPB performance is better than that of a single diaphragm wall (about 13% reduction) when the penetration depth is 90% of the hydrous layer thickness. This means that MPB can reduce seawater intrusion at lower cost than conventional barriers.
Seawater invasion (SWI) has occurred in many coastal regions of the world. With rising sea levels and uncontrolled production of fresh water from coastal areas, the seawater may further push inland, contaminating the available ground water. Effective measures need to be established to control the SWI so that underground water resources are optimally developed. Previous literature studies have proposed several strategies to prevent or mitigate SWI; this includes the installation of underground barriers, which may be hydraulic or physical in nature.
Hydraulic barriers can be divided into three types, positive, negative, and hybrid. In a forward barrier, fresh water is injected into the aquifer to raise the water table, which impedes the migration of seawater to the land. Fresh water is typically injected through a series of makeup wells along a shoreline, forming a fresh water watershed. Although some studies have demonstrated the effectiveness of the forward barrier, recent studies have shown that effective seawater rejection can only be achieved by injecting water at the toes of the seawater wedge. This highlights an important limitation of the forward barrier, considering that seawater wedges are never completely stationary in field scene, but move around with seasonal oscillations.
The negative barrier is to intercept seawater intrusion from pumping offshore. While it is possible to slow the migration of seawater to land, these barriers extract more fresh water than seawater, ultimately resulting in a reduction in the available groundwater resources. Furthermore, the method is only effective when the seawater production rate exceeds the fresh water production rate, involving considerable and continuous energy. The treatment of extracted underground seawater is also of interest. A hybrid hydraulic barrier combines positive and negative barriers. Fresh water is injected inland to knock off the seawater wedges, while seawater is drawn from near shore to slow its intrusion.
In addition to the above limitations, this measure also requires substantial operating and maintenance costs, since the filtering zone of the filter tubes is generally at risk of clogging and shrinkage when using these wells. The use of physical barriers as a method of SWI control has been the focus of some research. A physical barrier is a subsurface impermeable or semi-permeable structure built parallel to the coast. Two types of physical barriers are described in the literature: underground dams and water-stop walls. An underground dam is buried in the water-impermeable bottom of the aquifer, blocking only its lower part, leaving an opening in its upper part, allowing the natural discharge of fresh water into the sea. 7 of the 15 underground dams are specially designed to prevent the intrusion of seawater into the land and to protect the underground fresh water storage. A low-elevation underground dam can remove inland excess seawater faster than a high-elevation dam, while also more effectively reducing the expected increase in height of seawater wedges along the shoreline. The height of the dam body only needs to exceed the height of the seawater wedge body at an ideal construction position.
A second type of physical barrier is a diaphragm wall, which extends from the top of the aquifer to a predetermined depth. The closer the diaphragm wall is to the shoreline, the greater the penetration depth and the greater its effectiveness. The closer the diaphragm wall is to the coast, the greater the volume of underground fresh water. The performance of a diaphragm wall located at half-height from the shoreline depends not only on the depth of penetration but also on the ratio of groundwater flow velocity to density-driven seawater velocity.
Controlling the flow rate ratio not only helps to combat seawater intrusion better, but also increases fresh water storage to better utilize existing fresh water resources. This concept of joint action against seawater intrusion has never before been applied to physical barriers.
To solve this problem, a hybrid physical barrier (MPB) is proposed, which consists of an impermeable diaphragm wall close to the coast and a semi-permeable underground dam short on the sea-facing side of the diaphragm wall. The objective of the new MPB system is to increase the flow rate ratio and thereby further increase the driving capacity of the seawater wedge. Therefore, the main purpose of the embodiments of the present invention is: 1) researching the influence of the semi-permeable underground dam and the water-stop wall on the unsteady state seawater invasion dynamics; 2) the feasibility of MPB as a new SWI control method was evaluated.
Experimental automated image analysis techniques were used to quantify the major SWI parameters. The method can quantitatively analyze the influence of the obstacles on the change of the toe end position of the seawater wedge under the unsteady condition, and has higher space-time resolution. The agreement of the test results with the numerical predictions was evaluated using a seawa numerical model. Sensitivity analysis is then performed to assess the relevance of the effectiveness of each barrier to certain key design variables.
The experiment was carried out in a launder measuring 0.38m in length, 0.15m in height and 0.01m in width. The narrow basin makes it possible to simulate a two-dimensional system of the water-bearing layer cross-section of an unlimited coast. The water tank consists of a porous medium cavity and water tanks on two sides. The porous medium cavity is filled with glass beads with the average diameter of 1.1 mm. The beads were packed under saturated conditions to avoid air pollution. The beads were packed in three layers of material of similar thickness, each layer being carefully compacted. The resulting porous region is assumed to satisfy the uniform isotropy condition. The porous media chamber was separated from the two side tanks by two fine acrylic nets.
The left water tank is used for conveying fresh water to the system, and the right water tank is filled with seawater. Average of porous mediaThe permeability coefficient was 0.014 m/s. 200L of seawater solution is prepared before experiment, industrial salt is dissolved into fresh water with the concentration of 36.16g/L and the density of 1025kg/m3. Density measurements were made using a densitometer and manually using a mass/volume ratio. In order to distinguish seawater from fresh water, a red dye (food color) with a concentration of 0.15g/L was added to the seawater solution. In all experiments, the seawater solution was taken from 200L batches to ensure density and color uniformity between experiments.
The height (saturation thickness) of the aqueous layer synthesized in each test was 136 mm. The barrier is placed in front of the bead package. To form a semi-permeable underground dam, two divider plates are inserted into the porous media chamber, and fine water beads having an average diameter of 0.3mm are drawn into the space between the divider plates to a desired height. After the packaging is complete, the divider panel is carefully removed. The average permeability coefficient of the dam was also obtained by field measurements on experimental tanks (thinner grids on both sides), Kd0.0017 m/s. In field applications, typical grouting materials include cement-bentonite clays, which may have a permeability coefficient as low as 10-9m/s。
The diaphragm wall is made of a diaphragm material (plastic). The diaphragm walls are usually located less than or equal to twice the height of the aquifer from the shoreline and should be located in the area where the seawater wedge is active. To meet these conditions, in this test, the diaphragm wall was placed at half height from the aquifer. The seawater wedge distribution area in the background aquifer (base case) is first analyzed to ensure that the diaphragm wall is within the seawater wedge area. The depth of the water-stop wall is adjusted to ensure that the height of the water-stop wall and the aquifer at the bottom of the sand tank is kept below 40 percent of the opening, so as to ensure that the invasion length of the seawater is effectively reduced. It is worth noting that in practical on-site aquifers, the maximum wall depth of construction can reach 100 meters. In the MPB test, the positions of the water-stop wall and the semi-permeable dam are the same as those of other tests.
All experiments were recorded using a high-speed video camera (IDT Motion Pro X-series). A calibration method was used to relate the intensity of the recorded image to the salt concentration prior to each experiment. The calibration method included flushing the area with different concentrations of seawater solution and recording the light intensity for each concentration for each pixel. And analyzing the experimental image by using MATLAB software to obtain the intensity concentration parameter of the experimental image. The intensity-concentration conversion can be used to determine key parameters for SWI intrusion under non-steady state conditions.
At the beginning of each experiment, fresh water was injected at a constant rate from a large tank located above the left tank and the level of the fresh water was set high enough to keep the entire flask fully saturated with fresh water. The fresh water flux passes through the system from the inland boundary and flows out at the coastal boundary without flooding. In the seawater tank, the overflow outlet is adjusted to maintain a constant head of 129.7 mm. Excess seawater flows from the other large tank into the correct tank to ensure that any fresh water floating on the surface is flushed out until the density measurement becomes stable. The ultrasonic sensor is used for monitoring all water head values, and the precision is +/-0.2 mm. The head value is the energy consumed by the liquid in the water tank to overcome resistance during movement.
The fluctuation of the groundwater is simulated by changing the fresh water level. For each experiment, two different heads were set at the fresh water boundary, 135.7mm and 133.7mm in sequence, creating a head difference of dh 6mm (135.7-129.7) and dh 4mm (133.7-129.7), allowing the system to reach quasi-steady state conditions every 50 minutes. Head difference dh 6mm and dh 4mm correspond to hydraulic gradients of 0.0158 and 0.0105, respectively, consistent with previous laboratory studies using similar experimental setup and within the range of hydraulic gradients measured in part on site. The initial condition was to set a head of 135.7mm (dh 6mm) at the fresh water boundary. The denser seawater is admitted to a fully fresh water aquifer before the system first reaches a quasi-steady state. The fresh water level then drops to 133.7mm (dh ═ 4 mm) allowing the seawater wedges to migrate further inland. The fresh water head then returns to the initial value of dh 6mm, forcing the seawater wedges back towards the seawater boundary. It is also possible to check whether a hysteresis effect occurs during the experiment using the same differential pressure dh of 6mm as that set for the initial condition.
Wherein the values of the design variables may be as follows: for an underground dam: distance from sea boundaryLdThe value was 20 mm; height HdThe value was 70 mm; width WdThe value was 24 mm; water conductivity KdThe number is 0.0017 meters per second; for the impervious wall: distance L from sea boundarycThe value was 66 mm; opening degree XcThe value was 16 mm; width WcThe value was 20 mm.
Lc is the distance from the water barrier (i.e. physical barrier, water-proof wall) to the salt water boundary, Wc is the thickness of the water barrier (not considered in the patent), and Xc is the distance from the bottom of the water barrier to the bottom surface. Hd is the height of the weak permeable barrier (i.e. permeable wall) and Ld is the distance from the weak permeable barrier to the salt water boundary. Wd is the weak water permeable barrier thickness. The above parameters can be adjusted according to different situations.
To evaluate the effectiveness of different barriers, we first studied a background case without installed barriers as a benchmark for the investigated barrier cases. The effectiveness of the barrier is determined by the rate of decrease R ═ TL0-TLb)/TL0Characterization, wherein TL0And TLbRespectively the intrusion length before and after installation of the barrier.
The 3D model software for underground water flow and impurity transfer (MODFLOW) variable density flow code numerical model software (seacast) is widely used for solving various variable density benchmark problems, including seawater experiments with fresh water head boundary changes.
The regions are uniformly discretized with a grid size of 0.2 cm. The longitudinal dispersion was finally estimated to be 0.1cm and the transverse dispersion to be 0.05cm by trial and error. The spatial discretization satisfies a numerical stability criterion, i.e. the number of the relative proportions of convection and diffusion (mesh Peclet) is less than or equal to 4. All numerical experiments neglected molecular diffusion. Specific storage capacity is 10-6cm/L. The density of the fresh water and the seawater is 1000kg/m respectively3And 1025kg/m3. The concentration at the sea boundary was 36.16g/L, corresponding to the amount of salt required to prepare the sea solution.
To simulate an unsteady seawater intrusion, three stress cycles were used. Each stress cycle lasted 50 minutes, which is consistent with the time observed in the physical model for the system to reach an approximately steady state. Step of timeSet to 30 seconds. The fresh water side is provided with a variable water head boundary condition (C is 0g/L), the variable range is 135.7-133.7 mm, and the seawater side is provided with a constant water head 129.7mm (C is 36.16 g/L). The initial condition of the numerical model is a full fresh water aquifer. And applying boundary conditions to two sides of the system to enable the system to reach a first quasi-steady state condition. At the end of each stress cycle, the head and concentration of each grid serve as initial conditions for the next transition period. By assigning the permeability coefficient K to the celldThe underground dam was simulated into a numerical model at 0.0017m/s, which corresponds to the value measured in the setup, while the diaphragm wall was assumed to be impervious to water.
The embodiment of the utility model provides a deep analysis underground physics protective screen is to the influence of sea water invasion dynamics under the unsteady state condition. A new seawater intrusion control method is provided; a hybrid physical barrier MPB combines a water-impermeable diaphragm wall with a semi-permeable underground dam on the sea-side. Through indoor tests and numerical simulation, the influence of the semi-permeable underground dam, the water-stop wall and the MPB on the seawater invasion dynamics under different hydraulic gradients is researched. The sensitivity of the performance of these different barriers to some key design and hydrogeological parameters was then explored. The main results of the study are as follows:
an underground dam constructed of a semi-permeable material does not provide adequate control of the seawater intrusion process. If the groundwater flow is high enough to help the dam retain the intruding seawater wedges, the toe length may be reduced. They primarily affect the rate of the seawater migration process, but this effect is quickly dissipated by the seawater after the underground dam is fully saturated. In the case studied here, the semi-permeable dam eventually had a negative effect on the wedge length when the hydraulic gradient was low, resulting in toe end lengths that exceeded the toe end positions observed before dam installation.
As the hydraulic gradient becomes smaller or shallower, the necessity of installing a diaphragm wall in seawater intrusion control increases. In the case considered here, the diaphragm wall can reduce the toe length by up to 63%.
MPB initiates a visible uplift process in which fresh water flows at an increased velocity from below the opening in the wall, carrying the diffused flux of water over the underground dam and discharging it to the outlet. The lifting mechanism has a remarkable influence on the invasion length, and particularly when the hydraulic gradient is steep, the initial invasion length can be reduced by 70 percent, 42 percent compared with that of only arranging a water-stop wall, and 62 percent compared with that of only arranging an underground semi-permeable dam. Whereas the effectiveness of the single use of the diaphragm wall is limited to aquifer thicknesses where the wall opening size does not exceed 40%, MPB shows a good reduction in wall opening size extending to 60% of the aquifer thickness, which can show a 42% reduction over the use of a single diaphragm wall. Even penetration depths covering 90% of the hydrous layer thickness do not achieve this effect with a single barrier wall. This finding therefore means that when using MPB (particularly in deep-sea aquifer systems), there is the potential for saving construction costs by installing a diaphragm wall with a short penetration depth, while best ensuring protection against seawater ingress.
For equivalent sea-facing displacement of the cut-off wall, MPB exhibits better resistance to the invading seawater, reducing the invasion length by up to 40% compared with a single cut-off wall. This finding means that replacing the MPB impermeable wall to the sea not only ensures more reliable control of seawater intrusion, but also makes more efficient use of the existing fresh water volume, which is essential from a water resource management perspective. MPB effectiveness with permeability coefficient, diffusivity and seawater density of coastal groundwater systems ((s))<1025kg/m3) Is increased.
In field applications, MPB installations are expected to be more suitable for high permeability aquifers (e.g., sand, gravel) where groundwater flow rates are higher. In this case, the MPB has a more effective effect of increasing the inflow rate of fresh water over the intrusion rate of seawater within the distance between the dam body and the semi-permeable dam. In addition, real aquifers generally exhibit high dispersivity, often accompanied by micro/macro scale heterogeneity, which results in greater broadening of the saltwater-freshwater transition at different concentrations. Thus, the toe end of seawater intrusion may encounter inland groundwater (brine) at slightly higher concentrations. This low density contrast between the invading seawater and the fresh groundwater may therefore further enhance the MPB's ability, increase seawater flux, and repel seawater back into the sea. However, it is recommended that further experimentation and modeling be performed in future work to further investigate the utility of this system in the field. For example, the effect, three-dimensional effect, and bottom border morphology of the large scale model are worth further analysis. Our ongoing work focuses on this point and explores the effectiveness of MPB in heterogeneous aquifers, which will be one of the directions for future research.
Further, still include: a pair of screens for blocking porous media, which are respectively and correspondingly disposed at a communication position between the water flowing groove 1 and the first water tank 2 and a communication position between the water flowing groove 1 and the second water tank 3.
The beneficial effect of adopting the further scheme is that: due to the arrangement of the filter screen, the porous medium is prevented from flowing out of the launder, the reliability of the experimental device is improved, and the user experience is improved.
Further, the filter screen is an acrylic screen.
The beneficial effect of adopting the further scheme is that: the arrangement of the acrylic acid net prevents the porous medium from flowing out of the launder, improves the reliability of the experimental device, improves the user experience, and reduces the production cost.
Further, the porous medium is a plurality of glass beads, quartz sand or plastic beads.
The beneficial effect of adopting the further scheme is that: a plurality of glass beads are combined to form a porous medium, the accuracy of the experimental device is improved,
further, the diameter of the glass beads is 1.1 mm.
The beneficial effect of adopting the further scheme is that: the diameter of glass pearl is 1.1 millimeter, improves experimental apparatus's precision, improves experimental apparatus's reliability.
Further, still include: a first ultrasonic sensor 4 for measuring the energy consumed by the fresh water in the first water tank against resistance during movement, and a second ultrasonic sensor 5 for measuring the energy consumed by the seawater in the second water tank against resistance during movement, wherein the first ultrasonic sensor 4 is arranged on the top of the first water tank 2, and the second ultrasonic sensor 5 is arranged on the top of the second water tank 3.
The beneficial effect of adopting the further scheme is that: the ultrasonic sensor is used for measuring the energy consumed by liquid in the water tank in the movement process of overcoming resistance, so that the accuracy of experimental data is improved, and the fidelity of the experimental device is improved.
Further, still include: the first adjustable overflow valve 6 is arranged in the first water tank 2, the input end of the first adjustable overflow valve 6 is communicated with the inside of the first water tank 2, and the output end of the first adjustable overflow valve 6 is communicated with the outside; the second adjustable overflow valve 7 is arranged in the second water tank 3, the input end of the second adjustable overflow valve 7 is communicated with the inside of the second water tank 3, and the output end of the second adjustable overflow valve 7 is communicated with the outside.
The beneficial effect of adopting the further scheme is that: the setting of overflow valve with adjustable, the user of being convenient for adjusts the height of water tank water level according to actual need, is convenient for discharge the water that surpasss in the water tank and predetermine the water level outside the water tank through overflow valve with adjustable, improves the control precision of water tank water level.
Further, still include: the output end of the first adjustable overflow valve 6 is connected with one end of the first hose 8, and the other end of the first hose 8 is communicated with the outside; the output end of the second adjustable overflow valve 7 is connected with one end of the second hose 9, and the other end of the second hose 9 is communicated with the outside.
The beneficial effect of adopting the further scheme is that: the setting of hose for water to in the box carries out the drainage, the drainage of being convenient for is handled, improves user experience.
Further, the length of the launder 1 is 0.38 meter, the height of the launder 1 is 0.15 meter, and the width of the launder 1 is 0.01 meter.
The beneficial effect of adopting the further scheme is that: due to the special size design of the flume, the proximity of the experimental device to the actual seawater invasion is improved, and the accuracy of the experimental result is improved.
Further, the launder 1 further includes: the utility model provides a building structure, including water-stop wall 10 and infiltration wall 11, water-stop wall 10 and infiltration wall 11 all set up the inside of tye 1, water-stop wall 10 and infiltration wall 11 are platelike structure, infiltration wall 11 sets up the right side of water-stop wall 10, the bottom of water-stop wall 10 with there is overlap area at the top of infiltration wall 11, water-stop wall 10 with be provided with the clearance between the infiltration wall 11, the top of water-stop wall 10 with the top inner wall connection of tye 11, the bottom of infiltration wall 11 with the bottom inner wall connection of tye 1.
The beneficial effect of adopting the further scheme is that: the water-stop wall and the permeable wall are arranged and used for simulating the physical barrier, so that the accuracy of experimental data is improved, and a user can conveniently experiment the physical barrier.
Wherein, the lateral wall of water-stop wall and infiltration wall is equallyd divide and is supported with the lateral wall of tye respectively.
The water-stop wall is arranged at the position of three-quarter vertical height of the flume, the width of the water-stop wall is equal to that of the flume, the water-stop wall is made of plastic plates, and water is completely stopped on the section. And a plastic plate clamping groove for installing a water-stop wall is arranged in the water flowing groove. The permeable wall is arranged at the position of one half of the vertical height of the water flowing groove, the width of the permeable wall is equal to that of the water flowing groove, the permeable wall is a weak permeable wall, and the permeable wall is formed by a weak permeable porous medium (with a small permeability coefficient, which is reflected as a small medium particle size) wrapped by a stainless steel net. The relative positions of the water-stop wall and the permeable wall to the water flowing channel are not limited to the above regulations, and can be adjusted according to actual needs.
It should be noted that the experiment can be set as a series of comparative experiments of scenes, from no baffle to only a water-stop wall, only weak permeability, to a mixed wall, etc., comparing the migration and filtration of the salt water.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.
Claims (10)
1. An experimental apparatus for investigating a physical barrier for controlling seawater ingress, comprising: the system comprises a water flowing tank for simulating a coastal aquifer, a first water tank for loading fresh water and a second water tank for loading seawater; porous media are arranged in the launder, the launder is clamped between the first water tank and the second water tank, and the launder is respectively communicated with the first water tank and the second water tank.
2. The experimental apparatus for investigating a physical barrier against ingress of seawater as claimed in claim 1, further comprising: a pair of screens for blocking porous media, the pair of screens being respectively and correspondingly disposed at a communication position between the gutter channel and the first water tank and a communication position between the gutter channel and the second water tank.
3. The experimental set-up for investigating a physical barrier to seawater intrusion according to claim 2, wherein the screen is an acrylic screen.
4. The experimental apparatus for investigating a physical barrier to seawater intrusion according to claim 1, wherein the porous medium is a plurality of glass beads, a plurality of quartz sand or a plurality of plastic beads.
5. The experimental setup for investigating a physical barrier to seawater intrusion according to claim 4, wherein the glass beads are 1.1mm in diameter.
6. The experimental apparatus for investigating a physical barrier against ingress of seawater as claimed in claim 1, further comprising: the device comprises a first ultrasonic sensor and a second ultrasonic sensor, wherein the first ultrasonic sensor is used for measuring the energy consumed by the fresh water in the first water tank overcoming resistance during the movement process, the second ultrasonic sensor is used for measuring the energy consumed by the seawater in the second water tank overcoming resistance during the movement process, the first ultrasonic sensor is arranged at the top of the first water tank, and the second ultrasonic sensor is arranged at the top of the second water tank.
7. The experimental apparatus for investigating a physical barrier against ingress of seawater as claimed in claim 1, further comprising: the first adjustable overflow valve is arranged in the first water tank, the input end of the first adjustable overflow valve is communicated with the inside of the first water tank, and the output end of the first adjustable overflow valve is communicated with the outside; the second adjustable overflow valve is arranged in the second water tank, the input end of the second adjustable overflow valve is communicated with the inside of the second water tank, and the output end of the second adjustable overflow valve is communicated with the outside.
8. The experimental facility for investigating a physical barrier against ingress of seawater as claimed in claim 7, further comprising: the output end of the first adjustable overflow valve is connected with one end of the first hose, and the other end of the first hose is communicated with the outside; the output end of the second adjustable overflow valve is connected with one end of the second hose, and the other end of the second hose is communicated with the outside.
9. The experimental facility for investigating a physical barrier to seawater intrusion according to claim 1, wherein the length of the launder is 0.38m, the height of the launder is 0.15m, and the width of the launder is 0.01 m.
10. The experimental facility for investigating a physical barrier to seawater intrusion according to claim 1, wherein the launder further comprises: the water-stop wall and the infiltration wall, the water-stop wall and the infiltration wall all set up the inside of tye, the water-stop wall and the infiltration wall is platelike structure, the infiltration wall sets up the right side of water-stop wall, the bottom of water-stop wall with there is overlap area at the top of infiltration wall, the water-stop wall with be provided with the clearance between the infiltration wall, the top of water-stop wall with the top wall connection of tye, the bottom of infiltration wall with the bottom wall connection of tye.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114319404A (en) * | 2022-01-12 | 2022-04-12 | 中国海洋大学 | Underground curtain for preventing seawater invasion and purifying residual saline water and construction method thereof |
| CN114319222A (en) * | 2022-01-12 | 2022-04-12 | 中国海洋大学 | Adjustable underground curtain suitable for coastal underground reservoir and construction method thereof |
| CN114994141A (en) * | 2022-07-28 | 2022-09-02 | 广州海洋地质调查局三亚南海地质研究所 | Coastal aquifer hydrogeology investigation device |
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2020
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114319404A (en) * | 2022-01-12 | 2022-04-12 | 中国海洋大学 | Underground curtain for preventing seawater invasion and purifying residual saline water and construction method thereof |
| CN114319222A (en) * | 2022-01-12 | 2022-04-12 | 中国海洋大学 | Adjustable underground curtain suitable for coastal underground reservoir and construction method thereof |
| CN114994141A (en) * | 2022-07-28 | 2022-09-02 | 广州海洋地质调查局三亚南海地质研究所 | Coastal aquifer hydrogeology investigation device |
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