Water temperature stratification bay water taking particle entrainment simulation test system

Abstract

The invention provides a water temperature stratification bay water taking particle entrainment simulation test system which comprises a water tank system which comprises a first water tank and a second water tank; a water inlet is formed in one end of the first water tank, a water outlet is formed in the other end of the first water tank, and the second water tank is mounted on one side of the first water tank close to the water outlet and communicated with the first water tank; a water taking piece is arranged at one end of the second water tank away from the first water tank; the layered temperature control assembly is arranged in the first water tank and one end, close to the first water tank, of the second water tank, and is used for forming and maintaining a vertical water temperature layered structure in the water body of the water tank system; the particle putting assembly is used for putting particles into water bodies with different water temperatures; and the test assembly is used for measuring flow field information and temperature information in the water tank system. The system overcomes the defect that a single water tank cannot simulate bay water taking, can support bay water taking three-dimensional flow field and algae particle entrainment law research under water temperature layering, and is simple in structure, adjustable in parameter, low in test cost, high in repeatability and wide in popularization prospect.

Description

Technical Field

[0001] This invention relates to the field of water temperature stratification simulation and water intake hydraulic characteristic testing technology, and more specifically, to a water temperature stratification reservoir bay water intake particle entrainment simulation test system. Background Technology

[0002] Many reservoirs need to transport high-quality raw water to cities as drinking water sources. After the reservoirs are built and filled, the surface water comes into contact with the air, and heat from the air is directly transferred to the water. The surface water is directly affected by meteorological factors. Due to the decreasing distribution of solar radiation with water depth, deep reservoirs gradually form a stable water temperature stratification structure vertically under the influence of solar radiation. This water temperature structure further causes differences in water density, making it difficult for the upper and lower water layers to achieve convection diffusion. Strong surface sunlight allows phytoplankton to release oxygen through photosynthesis, resulting in a layer with richer dissolved oxygen, which is beneficial for the growth of phytoplankton. However, the lower layers have poor light conditions, making it difficult for phytoplankton to survive. Combined with the slow convection diffusion between water layers, this further leads to water quality deterioration.

[0003] To meet the needs of water supply, irrigation, and ecological regulation, numerous water intake projects are located in tributary reservoir bay areas. Compared to the main reservoir area, the water in the bay is driven by the main reservoir flow, but also has relatively independent local flow field characteristics. Bays are easily affected by backwater from the main stream, resulting in lower overall flow velocities. They are sensitive areas for algal growth and algal blooms, and the operation of their water intakes involves water quality control issues related to stratified water intake. Therefore, conducting physical model experiments on the entrainment effect of water intakes under stratified water conditions, and simulating the three-dimensional flow field distribution of water intake in reservoir bays under stratified water conditions and its entrainment characteristics on algal particles, is of great significance.

[0004] Current research on the entrainment effect at water intakes mainly relies on numerical simulations or prototype observations. While numerical simulations can predict flow field distribution, their boundary conditions are often overly idealized, making it difficult to accurately reflect the real entrainment process under complex temperature stratification environments. Furthermore, conventional reservoir temperature stratification intake simulation experiments use cold and hot water injection methods, allowing them to mix over a certain time and distance to form a stable stratified water body within the tank. However, the injected water carries initial kinetic energy, which easily disturbs the natural temperature stratification flow field primarily driven by buoyancy. Existing technologies, such as CN103938575B, employ a single tank structure, which can only simulate the temperature stratification flow field of the main reservoir area, failing to simulate the driving effect of the main reservoir flow on tributary bays, and even less able to study the local flow field characteristics of the bay intake under mainstream driving and its entrainment process of floating particles such as algae. Therefore, a undisturbed temperature stratification control device for simulating algal particle entrainment at reservoir bay intakes is currently lacking. Summary of the Invention

[0005] The purpose of this invention is to provide a simulated test system for particle entrainment in water intake from a reservoir with stratified water temperature, which addresses the shortcomings of existing technologies and solves the problems mentioned in the background.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A simulated experimental system for particle entrainment in water intake from a reservoir with temperature stratification includes: The water tank system includes a first water tank for simulating the main reservoir water flow and a second water tank for simulating the reservoir bay; the first water tank has an inlet at one end and an outlet at the other end, the second water tank is installed on one side of the first water tank near the outlet and is connected to the first water tank; the end of the second water tank away from the first water tank is provided with a water intake device; A stratified temperature control component is installed in the first water tank and the second water tank at the end near the first water tank, and is used to form and maintain a vertical water temperature stratification structure in the water body of the water tank system. Particle delivery component, used to deliver particles into water bodies of different temperatures; Test components are used to measure flow field and temperature information within the water tank system.

[0007] Furthermore, the layered temperature control assembly includes at least one heating unit disposed in the first water tank and the second water tank at the end near the first water tank and parallel to the bottom of the tank, and a temperature control unit connected to the heating unit.

[0008] Furthermore, the heating unit is an epoxy ultra-thin waterproof heating plate.

[0009] Furthermore, the test assembly includes a vertical temperature sensor chain with a measurement accuracy of 0.01℃. The vertical temperature sensor chain is arranged on the side walls of the first and second water tanks along the height direction of the water tank system.

[0010] Furthermore, the test components include a flow rate measurement unit and a flow volume measurement unit. The flow rate measurement unit is installed on the top of the part of the second water tank without the stratified temperature control component, and the flow volume measurement unit is located inside the water intake component.

[0011] Furthermore, the side wall of the second water tank is provided with slots for installing a vertical temperature sensor chain, and the slots are located above and below the connection between the water intake component and the second water tank.

[0012] Furthermore, the particle delivery assembly includes at least two delivery pipes disposed on the side wall of the second water tank and a pumping unit connected to the delivery pipes. The outlet ends of the delivery pipes are distributed at intervals along the height direction of the second water tank, and one outlet end is provided in each water temperature stratification.

[0013] Furthermore, the water intake component includes a water intake pipe and a valve installed on the water intake pipe, with one end of the water intake pipe connected to the side wall of the first water tank.

[0014] The present invention has at least the following advantages or beneficial effects: This application provides a water temperature stratification reservoir bay water intake particle entrainment simulation test system. Through a stratified temperature control component, a stable vertical water temperature stratification structure is formed and maintained in the water body of the water tank system. Compared with the traditional water injection and mixing method, this method avoids interference from the initial kinetic energy of the water flow and can more realistically simulate the water temperature stratification environment dominated by buoyancy in nature. By setting up an interconnected first and second water tank, the system can simultaneously simulate the main reservoir flow and the tributary bay, and reproduce the hydrodynamic process of the main reservoir flow driving the bay water flow, solving the fundamental deficiency that a single water tank structure cannot simulate the reservoir bay water intake process. The particle delivery component can achieve instantaneous or constant uniform delivery of simulated algae particles into water bodies with different water temperature stratifications according to experimental requirements; the testing component can comprehensively measure flow field information and temperature information. This system realizes the experimental simulation of natural water temperature stratification in the main reservoir and bay. It provides device support for measuring the three-dimensional flow field distribution of water intake in the bay under water temperature stratification environment and verifying the three-dimensional algal particle entrainment law at the water intake. The device has a simple structure and operation method, and the water temperature stratification structure and water intake scheme can be flexibly adjusted as needed. Moreover, the experimental cost is low, the repeatability is strong, and it has high prospects for promotion. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of a water temperature stratification reservoir bay water intake particle entrainment simulation test system provided by the present invention; Figure 2 This is a schematic diagram of the structure of the layered temperature control component provided by the present invention; Figure 3 This is a schematic diagram of the particle delivery component provided by the present invention.

[0017] Icons: 1. First water tank; 11. Inlet; 12. Outlet; 2. Second water tank; 21. Water intake component; 211. Water intake pipe; 212. Valve; 3. Layered temperature control component; 31. Heating unit; 4. Particle delivery component; 41. Delivery pipe; 42. Pumping unit; 51. Vertical temperature sensor chain; 52. Flow rate measurement unit; 53. Flow measurement unit. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] In reservoir water environment and engineering water intake studies, accurately simulating the temperature stratification structure of the main reservoir and its hydraulic driving process on tributary bays, and quantitatively analyzing the entrainment effect of the intake on suspended particles such as algae, is of great significance for optimizing water intake strategies and ensuring water supply quality. However, traditional physical model test systems struggle to form stable temperature stratification without disturbing the flow field, and their structure cannot simulate the interconnected hydrodynamic processes between the main reservoir and the bays. The following embodiments provide a solution.

[0020] Please refer to Figure 1 As shown, a simulated experimental system for particle entrainment during water intake from a reservoir with stratified water temperature includes a water tank system, a stratified temperature control component, a particle delivery component, and a testing component. The water tank system is used to construct the physical space simulating the main reservoir and the bay; the stratified temperature control component uses heating to undisturbedly form and maintain a vertical water temperature stratification structure in the water; the particle delivery component is used to precisely deliver particles, such as algae particles, to specific water temperature layers; and the testing component is used to comprehensively collect flow field, temperature, and water intake flow rate data. Through the coordinated operation of these components, the system can realistically reproduce the complex physical process of particle entrainment during water intake under stratified water temperature conditions, where the main reservoir flow drives the bay water flow, providing a reliable experimental platform for quantitative research.

[0021] Specifically, the water tank system includes a first water tank 1 for simulating the main reservoir's water flow and a second water tank 2 for simulating the reservoir bay. The first water tank 1 has an inlet 11 at one end and an outlet 12 at the other end to create a stable longitudinal water flow. By connecting external drive pipes to the inlet 11 and outlet 12, the inlet and outlet flow are kept constant, thus simulating the main reservoir's flow. In this embodiment, the first water tank is made of glass and has dimensions of 6.0m (length) × 0.5m (width) × 1.0m (height).

[0022] The second water tank 2 is also made of glass, with dimensions of 1.5m (length) × 1.0m (width) × 1.0m (height). The second water tank 2 is installed on one side of the first water tank 1, near the outlet 12. The distance between the side wall of the second water tank 2 near the outlet 12 and the outlet 12 is 1m, and the distance between it and the inlet 11 is 5m. The second water tank 2 is connected to the first water tank 1, allowing the main reservoir water flow to naturally flow into and drive the water movement within the bay, thus realistically simulating the hydraulic drive process of the main stream on the tributary bay in an actual reservoir. A water intake component 21 is located at the end of the second water tank 2 furthest from the first water tank 1, simulating the water intake in the bay area. The water intake component 21 includes a water intake pipe 211 and a valve 212 installed on the water intake pipe 211. One end of the water intake pipe 211 is connected to the side wall of the second water tank 2 to draw water from the second water tank 2, and the valve 212 is used to regulate and cut off the water intake flow. The end of the water collection pipe 211 can be connected to water sample collection devices such as buckets and beakers to collect water samples. Then, through methods such as filtration, weighing, or counting, the number of simulated particles entrained can be quantitatively analyzed to achieve a quantitative evaluation of the entrainment effect.

[0023] Please refer to Figure 1 and Figure 2 As shown, the stratified temperature control component 3 is disposed within the first water tank 1 and the second water tank 2 near the end of the first water tank 1, i.e., in the upstream section of the second water tank 2, to form and maintain a vertical water temperature stratification structure in the water body of the tank system. Specifically, the stratified temperature control component 3 includes at least one layer of heating units 31 disposed in the upstream section of the first water tank 1 and the second water tank 2 and parallel to the bottom of the tank, and a temperature control unit connecting all the heating units 31. The heating units 31 have a T-shaped structure, with both sides of the heating units 31 attached to the side walls of the first water tank 1, and a portion extending into the second water tank 2 and attached to the inner wall of the second water tank 2. The length of the heating unit 31 located in the second water tank 2 is one-third of the length of the second water tank 2. The heating units 31 directly heat their adjacent water layers through radiation and convection. Due to the slow heat conduction of water and the existence of density differences, after a period of heating and equilibrium, a stable and clear water layer with different temperatures can be formed vertically in the tank, i.e., water temperature stratification. This method avoids the interference of the initial kinetic energy of the water flow introduced by the traditional hot and cold water mixing method, and can more realistically simulate the vertical water temperature stratification environment formed by buoyancy in nature. In this embodiment, the heating unit 31 is an epoxy ultra-thin waterproof heating plate. The epoxy ultra-thin waterproof heating plate has the characteristics of thinness, high thermal efficiency, and good waterproof insulation performance, achieving uniform heating and minimal interference with the physical structure of the flow field. In order to facilitate long-term stable operation underwater, in addition to using an epoxy ultra-thin waterproof heating plate, other types of immersion electric heating elements can also be selected for the heating unit 31 according to the experimental requirements.

[0024] Temperature control units typically include programmable logic controllers, temperature sensors, relays, and power supply circuits. They are temperature control systems well-known to those skilled in the art. They can independently control the start-up, shutdown, and power of each heating unit 31, thereby simulating water temperature stratification with different intensities and numbers of layers.

[0025] Please refer to Figure 3 As shown, the particle delivery assembly 4 is used to deliver particles into water bodies of different temperatures. Specifically, the particle delivery assembly 4 includes at least two delivery pipes 41 disposed on the side wall of the second water tank 2 and a pumping unit 42 connected to the delivery pipes 41. The outlet ends of the delivery pipes 41 are spaced apart along the height direction of the second water tank 2, and one outlet end is provided in each target water temperature layer. In this way, by selecting different delivery pipes 41, particles can be accurately delivered into a specified water temperature layer to study the entrainment pattern of particles from different sources by the water intake. The pumping unit 42 is used to pump the simulated particle suspension stored in the container to the delivery pipes 41. In this embodiment, the pumping unit 42 is a Quattroflow QF30 low-shear pump with a speed controller. The low-shear pump can ensure that the simulated particles maintain their intact shape during transportation, avoiding particle breakage due to mechanical shear force, thereby ensuring the accuracy of subsequent entrainment quantitative analysis. The speed controller can precisely adjust the pump speed, thereby enabling the instantaneous high-flux release of simulated particles or the long-term constant and uniform low-flux release, greatly enhancing the flexibility and simulation realism of the experiment.

[0026] Please refer to this again. Figure 1 As shown, the test assembly is used to measure flow field and temperature information within the water tank system. The test assembly includes at least three vertical temperature sensor chains 51, a flow velocity measurement unit 52, and a flow rate measurement unit 53. The vertical temperature sensor chains 51 are miniature NTC thermistor chains with a measurement accuracy of 0.01℃. Multiple vertical temperature sensor chains 51 are arranged along the height direction of the water tank system on the side walls of the first water tank 1 and the second water tank 2, for continuous and high-precision monitoring of the water temperature at various points vertically throughout the entire water tank system, thereby accurately characterizing the formation, stabilization, and change process of the water temperature stratification structure. Furthermore, to better obtain a detailed local water temperature profile directly in front of the water intake, slots for mounting the vertical temperature sensor chains 51 are provided on the inner side wall of the second water tank 2. The slots are located above and below the connection between the water intake pipe 211 and the second water tank 2; this position allows for simultaneous monitoring of the vertical distribution of water temperature in the upstream and downstream areas of the water intake. When not drawing water, the vertical temperature sensor chain 51 is located in the slot. When drawing water, the vertical temperature sensor chain 51 needs to be removed first.

[0027] The flow velocity measurement unit 52 is installed above the portion of the second water tank 2 that is not equipped with the heating unit 31 (the end of the second water tank 2 furthest from the first water tank 1), and uses a non-contact method to measure the three-dimensional flow field information in the area near the water intake. The flow velocity measurement unit 52 is an acoustic Doppler current meter (ADV), such as a Nortek acoustic Doppler current meter, which is fixed in the water above the measurement point by a bracket, and can acquire flow velocity data at high frequency and high accuracy without disturbing the flow field.

[0028] The flow measurement unit 53 is located inside the water intake pipe 211 and is used to monitor the water intake flow rate in real time. The flow measurement unit 53 is typically an insertion type or pipe section flow meter, which is a conventional measuring device in this field.

[0029] During the experiment, water was first injected into the water tank system to establish a constant flow. Then, the stratified temperature control component 3 was activated, and the target temperature of each heating unit 31 was set through the temperature control unit. After a period of heating and equilibration, a stable vertical water temperature stratification was formed. Subsequently, the initial flow field and temperature field were measured using the testing component. Next, the particle delivery component 4 was activated to deliver simulated particles to the designated water temperature layer. Water was started by operating valve 212 of the water intake component 21, and the water flow rate was recorded by the flow measurement unit 53. During this process, the flow velocity measurement unit 52 continuously measured the flow field changes near the water intake. After the experiment, the particle concentration in the collected water sample was analyzed, and combined with the flow field, temperature, and flow rate data measured throughout the process, the entrainment law of particles under different water intake conditions under water temperature stratification can be systematically analyzed.

[0030] It should be noted that this system can simulate different operating conditions by adjusting several key parameters, including: setting different intake elevations within the maximum experimental water depth; adjusting the inflow rate of the straight flume within the range of 1.0 L / s to 20 L / s; setting the intake-to-inflow ratio to 1 / 5, 1 / 10, 1 / 20, 1 / 25, 1 / 40, 1 / 50, etc.; and changing the algae particle release method (instantaneous or continuous release) and release rate. During the experiment, the operating conditions can be optimized and adjusted based on the data patterns.

[0031] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A simulated experimental system for particle entrainment in water intake from a reservoir with stratified water temperature, characterized in that, include: The water tank system includes a first water tank for simulating the main reservoir water flow and a second water tank for simulating the reservoir bay; the first water tank has an inlet at one end and an outlet at the other end, the second water tank is installed on one side of the first water tank near the outlet and is connected to the first water tank; the end of the second water tank away from the first water tank is provided with a water intake device; A stratified temperature control component is installed in the first water tank and the second water tank at the end near the first water tank, and is used to form and maintain a vertical water temperature stratification structure in the water body of the water tank system. Particle delivery component, used to deliver particles into water bodies of different temperatures; Test components are used to measure flow field and temperature information within the water tank system.

2. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 1, characterized in that, The layered temperature control assembly includes at least one layer of heating units disposed in the first water tank and the second water tank at the end near the first water tank and parallel to the bottom of the tank, and a temperature control unit connected to the heating units.

3. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 2, characterized in that, The heating unit is an epoxy ultra-thin waterproof heating plate.

4. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 1, characterized in that, The test assembly includes a vertical temperature sensor chain with a measurement accuracy of 0.01℃. The vertical temperature sensor chain is set on the side walls of the first and second water tanks along the height direction of the water tank system.

5. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 1, characterized in that, The test components include a flow rate measurement unit and a flow volume measurement unit. The flow rate measurement unit is installed on the top of the part of the second water tank that is not equipped with the stratified temperature control component, and the flow volume measurement unit is located inside the water intake component.

6. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 4, characterized in that, The side wall of the second water tank is provided with slots for installing a vertical temperature sensor chain. The slots are located above and below the connection between the water intake component and the second water tank.

7. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 1, characterized in that, The particle delivery assembly includes at least two delivery pipes disposed on the side wall of the second water tank and a pumping unit connected to the delivery pipes. The outlet ends of the delivery pipes are distributed at intervals along the height direction of the second water tank, and one outlet end is provided in each water temperature stratification.

8. The water temperature stratification reservoir bay water intake particle entrainment simulation test system according to claim 1, characterized in that, The water intake device includes a water intake pipe and a valve installed on the water intake pipe, with one end of the water intake pipe connected to the side wall of the first water tank.

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