A water supply circulation control system and control method for experimental water tank

Abstract

A water supply circulation control system and control method for an experimental water tank, comprising an experimental water tank and a stabilizing water tank. One end of the experimental water tank and the stabilizing water tank is connected to each other and provided with a connecting pipe, through which the water flow in the experimental water tank is sent to the stabilizing water tank. The other end of the stabilizing water tank is provided with a water supply circulation control component, through which the water body is energized and then re-input into the experimental water tank through a water main pipe, so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe. The constant flow and non-constant flow generated by the present invention have the characteristics of stable flow regulation process, wide range and high precision. The flow control of the present invention adopts a distributed control system based on communication, and the flow control and detection hardware equipment are distributed to the site for installation, so that system failures are decentralized, and failure of a single flow detection or control device will not be directly coupled to a monitoring computer to cause system failure, and the overall operation reliability of the system is high.

Description

Technical Field

[0001] The invention relates to the field of automated monitoring, and in particular to a water supply circulation control system and a matching control method applied to experimental water tanks of different lengths, to achieve automated monitoring of flow. Background Art

[0002] At present, in water flow physical model laboratories, a water flow flume is often used as an experimental equipment. This water flow flume obtains the corresponding experimental parameters by simulating the basic laws of water flow characteristics and sediment movement.

[0003] The water supply circulation method of the water flow tank under the existing technology adopts two technologies: three-dimensional and planar, which are as follows:

[0004] The three-dimensional water supply circulation technology uses a flat water tower as a water supply device. Water is pumped from the reservoir into the flat water tower, and the water flow is controlled by the overflow tank to produce a constant flow. The water flow is then input into the water tank for testing, and finally discharged into the reservoir to complete the water circulation. The flow rate can reach 0.5m 3 / second. The design height of the horizontal water tower is generally 6 to 8 meters, and the volume is about 70m 3 It is built with steel structure or reinforced concrete structure.

[0005] But the shortcomings of the flat water tower water supply under the prior art are:

[0006] 1) The horizontal water tower can only be used for constant flow tests, not for non-constant flow tests. Moreover, when the constant flow needs to be changed, the operation is complicated and time-consuming.

[0007] 2) The overflow from the horizontal water tower is large, and the overflow will be directly discharged into the reservoir without participating in the test, so the overall water utilization efficiency is low;

[0008] 3) If the laboratory needs to build a horizontal water tower, it will take up more space and site, and the construction cost will be relatively high.

[0009] In order to solve several problems of water supply in horizontal water towers, the prior art later developed a planar water supply circulation method for water flow flumes. In this scheme, a reciprocating flow bidirectional pump and a flow meter are combined into a flow controller to replace the horizontal water tower, and a water flow circulation channel is formed by connecting the two ends of the flume through a pipe. After adding water, the water body circulates back and forth between the flume and the pipe, and no longer discharges into the reservoir. The flow controller controls the required flow. Since all the equipment is basically in the same plane, it is called a planar circulating water supply. Compared with the three-dimensional circulating water supply method, the planar circulating water supply method not only saves a lot of space, site and test water, but also can quickly convert and generate constant flow and non-constant flow within the effective flow range.

[0010] However, after a long period of operation and feedback, the field testers found that the planar circulating water supply method also has some insurmountable defects, as follows:

[0011] 1) The smoothness of the flow process is not ideal, especially at low water levels or when the flow is close to the top and end of the design flow;

[0012] 2) The length of the experimental water tank is limited, and the water level at the outlet is too low, causing air to enter the water pump;

[0013] 3) The water flow rate cannot be too large, otherwise it will cause the water pump to have air intake problems;

[0014] 4) The test water depth cannot be too low, which will also cause air intake in the water pump;

[0015] The above four problems are caused by the structure of the planar circulating water supply itself. In addition, it is difficult for the planar circulating water supply to achieve high-precision control of the flow rate over a wide range.

[0016] In summary, to date, there have been no public reports, discussions, or technologies that can be applied to water tanks of different lengths and can carry out water circulation tests with a full combination of high and low water levels and large and small flow rates. Therefore, there is an urgent need to solve this problem. Summary of the invention

[0017] In order to solve the above problems, the present invention provides a water supply circulation control system and control method for an experimental water tank based on a comprehensive analysis of the applicability of existing three-dimensional and planar water supply circulation technologies. The control system and control method, through a redesigned structure, enable the water in the water tank and the pipe to be exchanged stably and efficiently, and perform high-precision and stable control of the water flow rate. The study of the physical model of water flow carried out in the water tank can be achieved with high quality in any combination from low water level to high water level and from low flow rate to high flow rate.

[0018] The present invention is a water supply circulation control system and control method applied to an experimental water tank, and its specific structure and method are as follows:

[0019] A water supply circulation control system applied to an experimental water tank, comprising an experimental water tank and a stabilizing water tank, characterized in that:

[0020] One end of the experimental water tank and the stabilizing water tank is connected to a connecting pipe, through which the water flow in the experimental water tank is sent to the stabilizing water tank;

[0021] The other end of the stabilizing water tank is provided with a water supply circulation control component, through which the water body is energized and then re-introduced into the experimental water tank through the water main pipe, so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe;

[0022] The stabilizing pool is specifically a sedimentation pool excavated on the ground plane. The bottom height of the stabilizing pool is 1.0m to 2.5m lower than the bottom height of the experimental water tank, and the top height of the stabilizing pool is 0.2m to 0.5m higher than the designed maximum water level of the experimental water tank. The volume of the stabilizing pool is 50% to 100% of the volume of the experimental water tank. The pool wall of the stabilizing pool is provided with pipe openings, which are respectively connected to the connecting pipe for water inlet and the water supply circulation control component for water outlet. The number and aperture size of the pipe openings are determined according to the maximum water supply.

[0023] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that the water supply circulation control component includes a water delivery branch pipe, a flow meter, an electromagnetic flow converter, a flow data acquisition network, a flow controller, a monitoring computer, a water delivery control network, a frequency converter and a submersible pump, wherein there are 3 to 6 water delivery branch pipes, one end of each water delivery branch pipe is connected to the pipeline in the stabilizing water tank, and the other end of the water delivery branch pipe is connected to the water delivery main pipe after being collected, and the flow meter is specifically an electromagnetic flow sensor, which is installed in the water delivery branch pipe, and the flow meter is connected to the electromagnetic flow converter data signal, and the electromagnetic flow converter is connected to the flow controller data signal through the flow data acquisition network, and the flow controller is connected to the monitoring computer data signal set in the background, and the flow controller is connected to the frequency converter data signal through the water delivery control network, and the frequency converter is connected to the submersible pump inside the water delivery branch pipe set at the pipe mouth where the water delivery branch pipe is connected to the stabilizing water tank, and the submersible pump delivers water to the water delivery branch pipe.

[0024] The purpose of this design is that the water delivery branch pipes as the water outlets should be designed with small apertures and more in number (3 to 6). Compared with large-aperture connecting pipes, the solution with more small-aperture water delivery branch pipes can achieve wide-range and high-precision flow control of the experimental water tank, and the total cost will be more economical. The submersible pumps are distributed and installed inside the water delivery branch pipes at the pipe openings connected to the stabilizing water tank, so that the water delivery branch pipes with smaller apertures are connected to the main water delivery pipe after being collected, and the main water delivery pipe is directly connected to the experimental water tank.

[0025] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that the electromagnetic flow converter has an RS485 communication interface, and sends a flow signal to a flow controller through a flow data acquisition network that also uses RS485 communication. The flow controller is connected to the monitoring computer data signal through its RS232 bus, and the flow controller sends a command signal to a frequency converter with an RS485 communication interface through a water supply control network that uses RS485 communication.

[0026] The monitoring computer is connected to the flow controller via the RS232 bus, and control commands and data are sent according to the agreed communication protocol. The flow controller is connected to several flow meters via the RS485 bus to form a flow data acquisition network, and the flow data and status data of each flow meter are read according to the agreed communication protocol; and the flow controller is connected to several frequency converters via the RS485 bus to form a water delivery control network, and frequency conversion data is sent according to the agreed communication protocol, and the status data of each frequency converter is read to accurately control the working flow of the submersible pump corresponding to each pipeline, so as to achieve the purpose of accurately controlling the amount of water exchanged between the stabilizing water tank and the experimental water tank.

[0027] The above design automatically controls the flow of the experimental water tank, connects the flow controller with the frequency converter, flow meter, and submersible pump in a negative feedback control form, and ensures that the water tank test flow is released on demand, and the water volume can keep up in time when the water level in the tank rises, and can be discharged in time when it decreases.

[0028] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that each of the water delivery branch pipes is provided with a branch pipe gate valve, and the water delivery branch pipe is opened or closed by the branch pipe gate valve.

[0029] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that the specific number of the flow meter, electromagnetic flow converter, frequency converter and submersible pump is equal to the number of water supply branches, that is, each water supply branch is equipped with an independent flow meter, electromagnetic flow converter, frequency converter and submersible pump.

[0030] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that a tail valve is provided on the pipeline at the connection between the experimental water tank and the connecting pipe, and the water flow from the experimental water tank into the connecting pipe is opened or closed by the tail valve.

[0031] A water supply circulation control system applied to an experimental water tank according to the present invention is characterized in that one end of the connecting pipe is connected to the bottom of the experimental water tank, and the other end of the connecting pipe is connected to a connecting pipe opening opened on the wall of a stabilizing water tank, and the water flow of the experimental water tank is sent into the stabilizing water tank through the connecting pipe opening.

[0032] In the design of the connecting pipe opening serving as the water inlet, its aperture should be large so that the flow capacity is strong enough to facilitate the stabilizing pool to quickly and timely receive the water flowing into the experimental water tank.

[0033] A water supply circulation control method applied to an experimental water tank is based on the above-mentioned water supply circulation control system applied to an experimental water tank, and its specific steps are as follows:

[0034] 1) Confirm that all parts of the water supply circulation control assembly are installed correctly without abnormalities, open the branch gate valves of the water supply branch pipes and the tail valves of the experimental water tank, and fill the stabilizing pool with water until the water volume can meet the experimental water demand. Then start the monitoring computer and flow controller to set the flow control parameters, start the frequency converter and submersible pump to enter the operating state, and observe the actual flow measured by the flow meter. When the given flow and actual flow of the experimental water tank do not match, the monitoring computer remotely adjusts the flow control parameters to make the actual flow consistent with the given flow within the error range, taking into account the control parameters and errors of the monitoring computer, flow meter, and frequency converter to be determined within a reasonable range, and try to avoid the situation where individual parameters are biased towards the extreme values;

[0035] 2) The flow control parameters are preset to fixed values, and the parameters determined on the monitoring software of the monitoring computer are set as default mode, so that the entire water supply cycle control component enters the working state with the determined parameters after startup;

[0036] 3) The water flow of the experimental water tank is sent to the stabilizing water tank through the connecting pipe, and the water body is energized by the water supply circulation control component opened in the stabilizing water tank, and then it is input into the experimental water tank again through the water main pipe, so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe;

[0037] 4) In step 3, the flow data processing program of the monitoring computer is started, and the flow meter installed inside the water delivery branch pipe sends the measured flow information obtained to the flow controller through the electromagnetic flow converter and the flow data acquisition network connected to the data. The flow controller, as the upper monitoring unit, sends the flow data to the monitoring computer installed in the background for calculation. The monitoring computer compares the calculation result with the preset fixed value and feeds it back to the flow controller. The flow controller then sends the water delivery parameter signal to the frequency converter through the water delivery control network. The frequency converter controls the submersible pump installed inside the connection end of the water delivery branch pipe and the stabilizing water tank as a one-way water delivery execution unit to deliver water to the water delivery branch pipe. Each water delivery branch pipe collects the water flow to the water delivery main pipe and then inputs it into the experimental water tank again;

[0038] 5) During the operation of step 4), the flow controller automatically operates according to the calculated flow process curve and the feedback value measured by the flow meter. When it is confirmed that the flow meter feedback value of step 4) is consistent with the preset fixed value of the monitoring computer control program, the flow data processing program is exited, and the monitoring computer enters the system monitoring program state. At this time, the steady water and automatic modes can be selected to carry out various physical model tests of the experimental water tank in an orderly manner, and the test data are automatically generated in the specified directory;

[0039] 6) After the test is completed, shut down the entire system and export the test data record document for subsequent analysis and research.

[0040] A water supply circulation control method applied to an experimental water tank according to the present invention is characterized in that in the step 4), the measured or numerical simulation calculation results of the flow are stored in a designated directory of a monitoring computer, the flow of the pipeline in each time period is calculated by a flow scale, and the required flow process curve is formed after smoothing. When the test in step 5) starts, the flow process curve is called out to realize automatic control of the water tank flow.

[0041] A water supply circulation control system and control method applied to an experimental water tank of the present invention achieves the purpose of circulating water supply in pipelines and water tanks by combining water body stabilization with flow control. The water supply circulation control system of the present invention is based on the premise of stabilizing the water body, and a stabilizing water tank is specially designed as an intermediate buffer link for the water flow from the experimental water tank to the pipeline. This has never been used and designed in planar and three-dimensional water supply circulation equipment, and is also the key to the water supply circulation control system of the present invention being applicable to the construction of water tanks of any length.

[0042] The principle of stabilizing the water body in the stabilizing pool is that the minimum water level of the stabilizing pool should ensure that the submersible pump is fully submerged and the water level fluctuation is not large, and the submerged water depth of the submersible pump is stable and there is no air inhalation when the submersible pump is working. When the submersible pump is used as the execution device for the experimental water tank to transport water flow to the pipeline, the flow of the submersible pump is controllable and stable. The submersible pump is set inside the water delivery branch pipe at the pipe mouth where the water delivery branch pipe is connected to the stabilizing pool. The aperture of the water delivery branch pipe is small. The water delivery branch pipe is connected to the water delivery main pipe with a larger aperture. The water delivery main pipe is directly connected to the bottom of the experimental water tank at the same height. Under the above arrangement conditions, the flow control of each submersible pump is realized to achieve the flow control of the entire circulating water supply. In addition, the method of using a group of pumps to control the flow also has the outstanding advantage of dispersing faults. When a single submersible pump fails, it has little effect on the total flow, and the overall reliability of the system operation is more guaranteed.

[0043] The following beneficial effects are achieved by using a water supply circulation control system and control method applied to an experimental water tank of the present invention:

[0044] 1. The water supply circulation control system and control method for an experimental water tank of the present invention adopts a process method of a stabilizing tank and flow control to design a water supply circulation system for the water tank, providing a generally applicable water supply circulation technical solution for building experimental water tanks of different lengths;

[0045] 2. The water supply circulation control system and control method applied to the experimental water tank of the present invention adopts a pump group flow generation and confluence mode in which several submersible pumps operate in coordination, and the generated constant flow and non-constant flow have the characteristics of stable flow regulation process, wide range and high precision;

[0046] 3. The water supply circulation control system and control method applied to the experimental water tank of the present invention adopts a communication-based distributed control system for flow control. After the flow control and detection hardware equipment are distributed to the on-site installation, the system failure is also decentralized. When a single flow detection or control device fails, it will not be directly coupled to the monitoring computer to cause a system failure, and the reliability of the overall operation of the system is relatively high. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a specific structural schematic diagram of a water supply circulation control system and control method applied to an experimental water tank of the present invention;

[0048] Figure 2 It is a schematic diagram of the specific structure of the cross section of a water supply circulation control system and control method applied to an experimental water tank of the present invention;

[0049] Figure 3 It is a specific structural schematic diagram of a water supply circulation control component of a water supply circulation control system and control method applied to an experimental water tank of the present invention;

[0050] In the figure: 1-experimental water tank, 1a-tail valve, 2-steady water tank, 3-connecting pipe, 3a-connecting pipe mouth, 4-water main pipe, A-water supply circulation control component, A1-water branch pipe, A1a-branch pipe gate valve, A2-flow meter, A3-electromagnetic flow converter, A4-flow data acquisition network, A5-flow controller, A6-monitoring computer, A7-water supply control network, A8-frequency converter, A9-submersible pump. DETAILED DESCRIPTION

[0051] The following is a further description of a water supply circulation control system and a control method for an experimental water tank of the present invention in conjunction with the accompanying drawings and embodiments.

[0052] like Figure 1 to Figure 3 As shown, a water supply circulation control system applied to an experimental water tank comprises an experimental water tank 1 and a stabilizing water tank 2. One end of the experimental water tank and the stabilizing water tank are connected to each other and a connecting pipe 3 is provided. The water flow in the experimental water tank is sent to the stabilizing water tank through the connecting pipe.

[0053] The other end of the stabilizing water tank 2 is provided with a water supply circulation control component A, through which the water body is energized and then re-introduced into the experimental water tank through the water main pipe 4, so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe;

[0054] The stabilizing pool 2 is specifically a sedimentation pool excavated on the ground plane. The bottom height of the stabilizing pool is 1.0m to 2.5m lower than the bottom height of the experimental water tank 1, and the top height of the stabilizing pool is 0.2m to 0.5m higher than the designed maximum water level of the experimental water tank. The volume of the stabilizing pool is 50% to 100% of the volume of the experimental water tank. The pool wall of the stabilizing pool is provided with pipe openings, which are respectively connected to the connecting pipe 3 for water inlet and the water supply circulation control component A for water outlet. The number and aperture size of the pipe openings are determined according to the maximum water supply.

[0055] Taking a more common standard-sized stabilizing pool as an example, its internal dimensions are 8.8m long × 2.5m wide × 4m deep. The total water depth of the pool is 4m, of which the water depth above the ground level of the stabilizing pool is 1.8m, and the water depth below the ground level of the stabilizing pool is 2.2m. It is constructed of reinforced concrete, and the thickness of the pool bottom and walls are both 40cm.

[0056] like Figure 3 As shown, the water supply circulation control component A includes a water delivery branch pipe A1, a flow meter A2, an electromagnetic flow converter A3, a flow data acquisition network A4, a flow controller A5, a monitoring computer A6, a water delivery control network A7, a frequency converter A8 and a submersible pump A9, wherein there are 3 to 6 water delivery branch pipes (usually 4), one end of each water delivery branch pipe is connected to the pipeline in the stabilizing water tank 2, and the other end of the water delivery branch pipe is connected to the water delivery main pipe 4 after being collected, and the flow meter is specifically an electromagnetic flow sensor, which is installed in the water delivery branch pipe, and the flow meter is connected to the electromagnetic flow converter data signal, and the electromagnetic flow converter is connected to the flow controller data signal through the flow data acquisition network, and the flow controller is connected to the monitoring computer data signal set in the background, and the flow controller is connected to the frequency converter data signal through the water delivery control network, and the frequency converter is connected to the submersible pump inside the water delivery branch pipe set at the pipe mouth where the water delivery branch pipe is connected to the stabilizing water tank, and the submersible pump delivers water to the water delivery branch pipe.

[0057] The electromagnetic flow converter A3 has an RS485 communication interface, and sends a flow signal to the flow controller A5 through the flow data acquisition network A4 which also uses RS485 communication. The flow controller is connected to the monitoring computer A6 through its RS232 bus for data signal communication, and the flow controller sends a command signal to the frequency converter A8 which has an RS485 communication interface through the water supply control network (A7) which uses RS485 communication.

[0058] Each of the water delivery branch pipes A1 is provided with a branch pipe gate valve A1a, and the branch pipe gate valve is used to open or close the water delivery branch pipe.

[0059] The specific number of flowmeters A2, electromagnetic flow converters A3, frequency converters A8 and submersible pumps A9 is equal to the number of water branch pipes A1 (usually 4), that is, each water branch pipe is equipped with an independent flowmeter, electromagnetic flow converter, frequency converter and submersible pump.

[0060] A tail valve 1a is provided on the pipeline at the connection between the experimental water tank 1 and the connecting pipe 3, and the water flow from the experimental water tank into the connecting pipe is controlled by opening or closing the tail valve.

[0061] like Figure 2 As shown, one end of the connecting pipe 3 is connected to the bottom of the experimental water tank 1, and the other end of the connecting pipe is connected to the connecting pipe port 3a opened on the wall of the stabilizing water tank 2, through which the water flow of the experimental water tank is sent to the stabilizing water tank.

[0062] A water supply circulation control method applied to an experimental water tank is based on the above-mentioned water supply circulation control system applied to an experimental water tank, and its specific steps are as follows:

[0063] 1) Confirm that all parts of the water supply circulation control assembly A are installed correctly without abnormalities, open the branch gate valves A1a of the water supply branch pipe A1 and the tail valve 1a of the experimental water tank 1, and fill the stabilizing pool with water until the water volume can meet the experimental water demand. Then start the monitoring computer A6 and the flow controller A5 to set the flow control parameters, start the frequency converter A8 and the submersible pump A9 to enter the operating state, and observe the actual flow measured by the flow meter A2. When the given flow and the actual flow of the experimental water tank do not match, the monitoring computer remotely adjusts the flow control parameters to make the actual flow consistent with the given flow within the error range, taking into account the control parameters and errors of the monitoring computer, flow meter, and frequency converter to be determined within a reasonable range, and try to avoid the situation where individual parameters are biased towards the extreme values;

[0064] Usually, the flowmeter A2 diameter corresponds to 3% of the full scale as the allowable deviation.

[0065] 2) The flow control parameters are preset to fixed values, and the parameters determined on the monitoring software of the monitoring computer A6 are set as default mode, so that the entire water supply cycle control component A enters the working state with the determined parameters after startup;

[0066] 3) The water flow of the experimental water tank is sent to the stabilizing water tank 2 through the connecting pipe 3, and the water body is energized by the water supply circulation control component A opened in the stabilizing water tank, and then it is sent to the experimental water tank again through the water main pipe 4, so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe;

[0067] 4) In step 3, the flow data processing program of the monitoring computer A6 is started, and the flow meter A2 set inside the water delivery branch pipe A1 sends the measured flow information obtained to the flow controller A5 through the electromagnetic flow converter A3 and the flow data acquisition network A4 connected to the data. The flow controller, as the upper monitoring unit, sends the flow data to the monitoring computer A6 set in the background for calculation. The monitoring computer compares the calculation result with the preset fixed value and feeds it back to the flow controller. The flow controller then sends the water delivery parameter signal to the frequency converter A8 through the water delivery control network A7. The frequency converter controls the submersible pump A9 set inside the connection end of the water delivery branch pipe and the stabilizing water tank as a one-way water delivery execution unit to deliver water to the water delivery branch pipe. Each water delivery branch pipe collects the water flow to the water delivery main pipe 4 and then inputs it into the experimental water tank again;

[0068] 5) During the operation of step 4), the flow controller A5 automatically operates according to the calculated flow process curve and the feedback value measured by the flow meter. When it is confirmed that the flow meter feedback value of step 4) is consistent with the preset fixed value of the control program of the monitoring computer A6, the flow data processing program is exited, and the monitoring computer enters the system monitoring program state. At this time, the steady water and automatic modes can be selected to carry out various physical model tests of the experimental water tank in an orderly manner, and the test data are automatically generated in the specified directory;

[0069] 6) After the test is completed, shut down the entire system and export the test data record document for subsequent analysis and research.

[0070] Under normal circumstances, the physical model tests of the experimental flume are carried out by repeating steps 4 to 6, setting different process curve files each time, and the flow data processing program and system monitoring program automatically run and export the test result files. When the system changes the application occasion, steps 1 to 3 are performed step by step according to the actual situation of the model.

[0071] In step 4), the measured or numerical simulation calculation results of the flow are stored in the specified directory of the monitoring computer, the flow of the pipeline in each time period is calculated by the flow scale, and the required flow process curve is formed after smoothing. When the test in step 5) starts, the flow process curve is called out to realize automatic control of the water tank flow.

[0072] Example 1 - Physical model test study on flow characteristics of cavity-type silt-promoting dike section:

[0073] The deviation of each flow process line of the model is within ±2%, the deviation of the test time of each velocity measurement point and the prototype time is within ±0.5h, the velocity process line morphology of the test result and the measured data is basically consistent, and the statistical average velocity deviation is within ±10%. This shows that the accuracy requirements of the simulated water flow flume test provided by the present invention for tidal current simulation provide a guarantee for the reliability of the model test results.

[0074] Example 2 - Physical model test study on Wusongkou estuary morphology optimization (sediment start-up flow velocity test):

[0075] In the verification test, the deviation of each flow process line of the model is within ±%2, and the deviation of the repeated test is within ±4%. This shows that the water flow of the flume provided by the present invention meets the requirements of the moving bed test and lays a foundation for the successful implementation of the bottom sand scouring and silting test.

[0076] The present invention discloses a water supply circulation control system and a control method for an experimental water tank. The water tank water supply circulation system is designed by using a process method of a stabilizing tank plus flow control, and a generally applicable water supply circulation technical scheme is provided for building experimental water tanks of different lengths. The present invention adopts a pump group flow generation and convergence mode in which a plurality of submersible pumps operate in coordination, and the generated constant flow and non-constant flow have the characteristics of stable flow regulation process, wide range and high precision. The flow control of the present invention adopts a distributed control system based on communication. After the flow control and detection hardware equipment are distributed to the site for installation, the system failure is also decentralized. After a single flow detection or control equipment fails, it will not be directly coupled to the monitoring computer to cause a system failure, and the reliability of the overall operation of the system is relatively high.

[0077] The present invention discloses a water supply circulation control system and a control method for an experimental water tank, which are suitable for constructing long and short water tanks and can carry out a full combination of high and low water levels and large and small flow rates. The water supply circulation control system and a control method are suitable for the field of physical model tests of various experimental water tanks.

Claims

1. A water supply circulation control system for an experimental water tank, comprising an experimental water tank (1) and a stabilizing tank (2), characterized in that: One end of the experimental water tank (1) and the stabilizing water tank (2) is connected to a connecting pipe (3), through which the water flow in the experimental water tank is sent to the stabilizing water tank; The other end of the stabilizing water tank (2) is provided with a water supply circulation control component (A), through which the water body is energized and then input into the experimental water tank again through the water main pipe (4), so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water main pipe; The stabilizing pool (2) is specifically a sedimentation pool excavated on the ground plane, the bottom height of the stabilizing pool is 1.0m to 2.5m lower than the bottom height of the experimental water tank (1), and the top height of the stabilizing pool is 0.2m to 0.5m higher than the designed maximum water level of the experimental water tank, and the volume of the stabilizing pool is 50% to 100% of the volume of the experimental water tank. The pool wall of the stabilizing pool is provided with pipe openings, which are respectively connected to the water inlet connecting pipe (3) and the water supply circulation control component (A) for the water outlet, and the number and aperture size of the pipe openings are determined according to the maximum water supply; The water supply circulation control component (A) comprises a water delivery branch pipe (A1), a flow meter (A2), an electromagnetic flow converter (A3), a flow data acquisition network (A4), a flow controller (A5), a monitoring computer (A6), a water delivery control network (A7), a frequency converter (A8) and a submersible pump (A9), wherein there are 3 to 6 water delivery branch pipes, one end of each water delivery branch pipe is connected to the pipeline in the stabilizing water tank (2), and the other end of the water delivery branch pipe is connected to the water delivery main pipe (4) after being collected, and the flow meter is specifically an electromagnetic flow sensor, which is installed in the water delivery branch pipe, and the flow meter is connected to the electromagnetic flow converter data signal, and the electromagnetic flow converter is connected to the flow controller data signal through the flow data acquisition network, and the flow controller is connected to the monitoring computer data signal arranged in the background, and the flow controller is connected to the frequency converter data signal through the water delivery control network, and the frequency converter is connected to the submersible pump inside the water delivery branch pipe arranged at the pipe mouth where the water delivery branch pipe is connected to the stabilizing water tank, and the submersible pump delivers water to the water delivery branch pipe; The electromagnetic flow converter (A3) has an RS485 communication interface, and sends a flow signal to a flow controller (A5) through a flow data acquisition network (A4) that also uses RS485 communication. The flow controller is connected to a monitoring computer (A6) via a RS232 bus provided therein, and the flow controller sends a command signal to a frequency converter (A8) having an RS485 communication interface through a water delivery control network (A7) that uses RS485 communication. The water delivery branch pipes (A1) are each provided with a branch pipe gate valve (A1a), and the branch pipe gate valve is used to open or close the water delivery branch pipe; The specific number of the flow meter (A2), electromagnetic flow converter (A3), frequency converter (A8) and submersible pump (A9) is equal to the number of water delivery branch pipes (A1), that is, each water delivery branch pipe is equipped with an independent flow meter, electromagnetic flow converter, frequency converter and submersible pump; A tail valve (1a) is provided on the pipeline at the connection between the experimental water tank (1) and the connecting pipe (3), and the water flow from the experimental water tank into the connecting pipe is opened or closed by the tail valve.

2. A water supply circulation control system for an experimental water tank as claimed in claim 1, characterized in that: One end of the connecting pipe (3) is connected to the bottom of the experimental water tank (1), while the other end of the connecting pipe is connected to a connecting pipe opening (3a) provided on the wall of the stabilizing water tank (2), through which the water flow of the experimental water tank is sent to the stabilizing water tank.

3. A water supply circulation control method applied to an experimental water tank, based on the water supply circulation control system applied to an experimental water tank described in claim 1 or claim 2, wherein the specific steps are as follows: 1) Confirm that all components of the water supply circulation control assembly (A) are installed correctly without any abnormality. Open the branch gate valves (A1a) of the water supply branch pipe (A1) and the tail valve (1a) of the experimental water tank (1) and fill the stabilizing pool with water until the water volume can meet the experimental water demand. Then start the monitoring computer (A6) and the flow controller (A5) to set the flow control parameters, start the frequency converter (A8) and the submersible pump (A9) to enter the operating state, and observe the actual flow measured by the flow meter (A2). When the given flow and the actual flow of the experimental water tank do not match, the monitoring computer remotely adjusts the flow control parameters to make the actual flow and the given flow consistent within the error range. The control parameters and errors of the monitoring computer, flow meter, and frequency converter are determined within a reasonable range to avoid the situation where individual parameters are biased to the extreme value. 2) The flow control parameters are preset to fixed values, and the parameters determined on the monitoring software of the monitoring computer (A6) are set as default mode, so that the entire water supply cycle control component (A) enters a working state with the determined parameters after startup; 3) The water flow of the experimental water tank is sent into the stabilizing water tank (2) through the connecting pipe (3), and the water body is energized by the water supply circulation control component (A) provided in the stabilizing water tank, and then is sent into the experimental water tank again through the water supply main pipe (4), so that the water body is continuously and effectively circulated through the experimental water tank, the connecting pipe, the stabilizing water tank and the water supply main pipe; 4) In step 3, the flow data processing program of the monitoring computer (A6) is started, and the flow meter (A2) installed inside the water delivery branch pipe (A1) sends the measured flow information obtained to the flow controller (A5) through the electromagnetic flow converter (A3) and the flow data acquisition network (A4) connected to the data. The flow controller, as the upper monitoring unit, sends the flow data to the monitoring computer (A6) installed in the background for calculation. The monitoring computer compares the calculation result with the preset fixed value and feeds it back to the flow controller. The flow controller then sends the water delivery parameter signal to the frequency converter (A8) through the water delivery control network (A7). The frequency converter controls the submersible pump (A9) installed inside the connection end of the water delivery branch pipe and the stabilizing water tank as a one-way water delivery execution unit to deliver water to the water delivery branch pipe. Each water delivery branch pipe collects the water flow to the water delivery main pipe (4) and then inputs it into the experimental water tank again. 5) During the operation of step 4), the flow controller (A5) automatically operates according to the calculated flow process curve and the feedback value measured by the flow meter. When it is confirmed that the flow meter feedback value of step 4) is consistent with the preset fixed value of the control program of the monitoring computer (A6), the flow data processing program is exited, and the monitoring computer enters the system monitoring program state. At this time, the steady water and automatic modes can be selected to carry out various physical model tests of the experimental water tank in an orderly manner, and the test data are automatically generated in the specified directory; 6) After the test is completed, shut down the entire system and export the test data record document for subsequent analysis and research.

4. A water supply circulation control method for an experimental water tank as claimed in claim 3, characterized in that: In the step 4), the flow measurement or numerical simulation calculation result document is stored in the specified directory of the monitoring computer (A6), the flow rate of the pipeline in each time period is calculated by the flow scale, and the required flow process curve is formed after smoothing. When the test in step 5) starts, the flow process curve is called out to realize automatic control of the water tank flow.

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