Sensitivity testing device for optical fiber distributed temperature measurement of drainage pipeline

Abstract

The utility model discloses a sensitivity testing device for optical fiber distributed temperature measurement of a drainage pipeline, which relates to the technical field of pipeline detection and comprises a heat preservation water tank, a first water pump, an experimental pipeline, a simulated damage water supply tank, a second water pump, a simulated mixed connection water supply tank, a third water pump, an optical fiber temperature measurement component and a PLC (Programmable Logic Controller), the heat-insulating water tank communicates with the experimental pipeline through a first water pump; the simulated damage water supply tank is communicated with the side wall of the experimental pipeline through a second water pump; the simulation mixed connection water supply tank is communicated with the experiment pipeline through a third water pump; the optical fiber temperature measurement assembly comprises a light source demodulation device and an optical fiber, and the optical fiber is connected with the light source demodulation device and distributed in the experiment pipeline. According to the sensitivity testing device for the optical fiber distributed temperature measurement of the drainage pipeline, the experimental pipeline simulates the scene where the existing drainage pipeline is located, and the temperatures measured by the temperature sensor and the optical fiber temperature measurement assembly are compared, so that an experimenter can conveniently correct and debug the optical fiber temperature measurement assembly.

Description

Technical Field

[0001] The utility model relates to the technical field of pipeline detection, in particular to a sensitivity test device for distributed optical fiber temperature measurement of drainage pipelines. Background Technique

[0002] Drainage pipelines are important urban infrastructure and play an important role in improving the urban water environment quality. Due to reasons such as lagging pipe network construction, uneven ground settlement, construction quality of pipe materials and interfaces, and internal corrosion of pipes, the problems of damage and misconnection of rainwater and sewage pipelines are serious. On the one hand, a large amount of external water such as groundwater and rainwater enters the sewage pipeline, resulting in low biodegradability of the influent of the sewage treatment plant, high treatment costs, and ineffective utilization of sewage treatment capacity; on the other hand, some sewage is misconnected into the rainwater pipeline and finally directly discharged into the river, resulting in a low sewage collection rate. Therefore, in response to the need for improving the quality and efficiency of urban sewage treatment in China, it is urgent to detect and locate the problem points such as damage and misconnection of the drainage pipe network, and on this basis, take targeted pipeline repair and renovation measures.

[0003] As a real-time monitoring technology, distributed optical fiber temperature measurement senses the temperature of the surrounding medium by laying optical cables longitudinally, determines the abnormal temperature points and gives real-time warnings. In the detection of drainage pipelines, as a distributed real-time "auscultation" technology for the water temperature signal inside the pipeline, it can accurately locate the problem points of inflow and infiltration caused by damage, misconnection, etc. by identifying abnormal water temperatures inside the pipeline. Compared with the traditional closed-circuit television detection technology, distributed optical fiber temperature measurement does not require plugging and dewatering operations, does not interfere with the operation of drainage pipelines, and can be implemented under the condition of high water level in the pipeline. In addition, it also has the advantages of all-weather spatio-temporal high-frequency observation, so it can further improve the reliability of identifying pipeline problem points, especially the accurate identification of dynamic inflow and infiltration points of external water.

[0004] Noise data caused by equipment operation is quite common in distributed optical fiber temperature measurement, and the quality of temperature data directly affects the reliability of data analysis and result determination. Especially when the water temperature difference between the inflowing and infiltrating external water and the misconnected sewage and the pipeline water temperature is small, unreasonable identification of the noise level will cause misjudgment of the diagnosis results. Therefore, it is necessary to reasonably determine the noise background value of optical fiber temperature measurement data and the sensitivity of the optical fiber temperature measurement system for detecting problem points of drainage pipelines.

[0005] How to develop a sensitivity test device for distributed optical fiber temperature measurement of drainage pipelines, simulate the environment of existing drainage pipelines, and realize the calibration and debugging of the sensitivity of the optical fiber temperature measurement components inside the pipeline has become a technical problem that needs to be solved urgently by those skilled in the art. Content of the Utility Model

[0006] The purpose of the present utility model is to provide a sensitivity test device for distributed optical fiber temperature measurement in drainage pipes, so as to solve the problems listed in the background art.

[0007] To solve the above technical problems, the present utility model adopts the following technical solutions:

[0008] A sensitivity test device for distributed optical fiber temperature measurement in drainage pipes of the present utility model includes a heat preservation water tank, a first water pump, an experimental pipeline, a simulated breakage water supply tank, a second water pump, a simulated connection mixing water supply tank, a third water pump, an optical fiber temperature measurement component and a PLC controller. The water outlet of the heat preservation water tank is communicated with the water inlet of the experimental pipeline through a water supply pipe, and the first water pump is installed on the water supply pipe. The water outlet of the experimental pipeline is communicated with the water inlet of the heat preservation water tank through a drain pipe;

[0009] The simulated breakage water supply tank is communicated with the side wall of the experimental pipeline through the second water pump; the simulated connection mixing water supply tank is communicated with a tee joint on the experimental pipeline through the third water pump;

[0010] The optical fiber temperature measurement component includes a light source demodulation device and an optical fiber. Both ends of the optical fiber are connected to the light source demodulation device, and the middle part of the optical fiber is distributed in the experimental pipeline;

[0011] The heat preservation water tank, the first water pump, the simulated breakage water supply tank, the second water pump, the simulated connection mixing water supply tank, the third water pump and the optical fiber temperature measurement component are all electrically connected to the PLC controller.

[0012] Preferably, the heat preservation water tank, the simulated breakage water supply tank and the simulated connection mixing water supply tank are all equipped with a screen display and a temperature control device.

[0013] Preferably, the experimental pipeline includes a large-diameter pipe, a reducing joint and a small-diameter pipe. The large-diameter pipe is communicated with the small-diameter pipe through the reducing joint, and the large-diameter pipes are connected through the tee joint;

[0014] It further includes an inflow and infiltration port, and the inflow and infiltration port is opened on the side walls of the large-diameter pipe and the small-diameter pipe.

[0015] Preferably, the whole experimental pipeline is in a U shape, and a bracket is fixedly installed below the experimental pipeline. A temperature sensor is installed on the side wall of the experimental pipeline, and the temperature sensor is electrically connected to the PLC controller.

[0016] Preferably, the simulated breakage water supply tank is communicated with the inflow and infiltration port through a simulated breakage water inlet pipe, and the second water pump is communicated with the main water pipe of the simulated breakage water inlet pipe. An inflow and infiltration control valve is installed on the branch water pipe of the simulated breakage water inlet pipe, and the inflow and infiltration control valve is electrically connected to the PLC controller.

[0017] Preferably, the simulated mixed connection water supply tank is communicated with the three-way joint through a simulated mixed connection water inlet pipe, and a third water pump is communicated on the simulated mixed connection water inlet pipe close to the simulated mixed connection water supply tank. A mixed connection water volume control valve is installed on the simulated mixed connection water inlet pipe far from the third water pump, and the mixed connection water volume control valve is electrically connected to the PLC controller.

[0018] Preferably, it further includes a water storage tank. The overflow port of the heat preservation water tank is communicated with the water storage tank. The water storage tank is respectively communicated with the simulated damaged water supply tank and the simulated mixed connection water supply tank through a water supply pipe. A water supply pump is communicated on one side of the water supply pipe close to the water storage tank. Water supply control valves are respectively installed on one side of the water supply pipe close to the simulated damaged water supply tank and the simulated mixed connection water supply tank, and the water supply control valves are electrically connected to the PLC controller.

[0019] Compared with the prior art, the beneficial technical effects of the present utility model are as follows:

[0020] The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline of the present utility model can simulate the scenarios of mixed connection, damage, leakage and diameter change on the existing drainage pipeline through the experimental pipeline, and compare the temperature data measured by the temperature sensor and the optical fiber temperature measurement component at the mixed connection, inflow and infiltration and diameter change points, which is convenient for experimental personnel to identify and determine the noise and detection sensitivity of the optical fiber temperature measurement component in the experimental pipeline, and is beneficial for experimental personnel to calibrate and debug the optical fiber temperature measurement component; further, it can also ensure the water inlet and return water efficiency in the experimental pipeline, and avoid water shortage and dry burning of the simulated damaged water supply tank and the simulated mixed connection water supply tank. Description of the Drawings

[0021] The following further explains the present utility model in conjunction with the description of the drawings.

[0022] Figure 1 It is the layout diagram of the sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline of the present utility model;

[0023] Figure 2 It is the assembly schematic diagram of the optical fiber temperature measurement component and the experimental pipeline of the present utility model;

[0024] Figure 3 It is the three-dimensional schematic diagram of the experimental pipeline of the present utility model.

[0025] Description of reference numerals: 1, heat preservation water tank; 2, water supply pipe; 3, first water pump; 4, simulated damaged water supply tank; 5, second water pump; 6, simulated damaged water inlet pipe; 7, influent and infiltration control valve; 8, simulated mixed connection water supply tank; 9, third water pump; 10, simulated mixed connection water inlet pipe; 11, mixed water volume control valve; 12, water storage tank; 13, water supply pump; 14, water supply control valve; 15, water supply pipe; 16, optical fiber temperature measurement component; 1601, light source demodulation device; 1602, optical fiber; 17, large-diameter pipe; 18, reducing joint; 19, small-diameter pipe; 20, influent and infiltration port; 21, bracket; 22, tee joint; 23, temperature sensor; 24, drain pipe. Detailed implementation manners

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0027] As Figures 1-3 shown, a sensitivity test device for distributed optical fiber temperature measurement of a drainage pipe includes a heat preservation water tank 1, a first water pump 3, an experimental pipeline, a simulated damaged water supply tank 4, a second water pump 5, a simulated mixed connection water supply tank 8, a third water pump 9, an optical fiber temperature measurement component 16 and a PLC controller. The water outlet of the heat preservation water tank 1 is communicated with the water inlet of the experimental pipeline through a water supply pipe 2, and the first water pump 3 is installed on the water supply pipe 2. The water outlet of the experimental pipeline is communicated with the water inlet of the heat preservation water tank 1 through a drain pipe 24.

[0028] The simulated damaged water supply tank 4 is communicated with the side wall of the experimental pipeline through the second water pump 5; the simulated mixed connection water supply tank 8 is communicated with a tee joint 22 on the experimental pipeline through the third water pump 9.

[0029] As Figure 2 shown, the optical fiber temperature measurement component 16 includes a light source demodulation device 1601 and an optical fiber 1602. Both ends of the optical fiber 1602 are connected to the light source demodulation device 1601, and the middle part of the optical fiber 1602 is distributed in the experimental pipeline.

[0030] The heat preservation water tank 1, the first water pump 3, the simulated damaged water supply tank 4, the second water pump 5, the simulated mixed connection water supply tank 8, the third water pump 9 and the optical fiber temperature measurement component 16 are all electrically connected to the PLC controller. Further, the PLC controller can collect and store the flow rate and water temperature inside the experimental pipeline.

[0031] Specifically, the heat preservation water tank 1, the simulated damaged water supply tank 4 and the simulated mixed connection water supply tank 8 are all provided with a display screen and a temperature control device.

[0032] As Figure 3 shown, the experimental pipeline includes a large-diameter pipe 17, a reducing joint 18, and a small-diameter pipe 19. The large-diameter pipe 17 is connected to the small-diameter pipe 19 through the reducing joint 18, and the large-diameter pipes 17 are connected through the tee joint 22;

[0033] It further includes an influent and infiltration port 20, which is opened on the side walls of the large-diameter pipe 17 and the small-diameter pipe 19. Further, there are multiple influent and infiltration ports. The experimental pipeline simulates the diameter-changing scenario of the drainage pipeline in reality through the large-diameter pipe, the reducing joint, and the small-diameter pipe, simulating the influence of the flow velocity on the temperature after the water flow passes through the diameter change. Further, the phenomenon of mixed connection in the real drainage pipeline is simulated through the tee joint. The problem of damage to the drainage pipeline in reality is simulated through the influent and infiltration port, approaching the environment where the real drainage pipeline is located. The temperature changes caused by the external water flow mixed at the tee joint and / or the influent and infiltration port and the influence of the water flow after the diameter change on the temperature are monitored through the optical fiber, facilitating the experimenter to calibrate and debug the measurement sensitivity at specific points on the optical fiber and improving the sensitivity of the optical fiber temperature measurement component test.

[0034] Specifically, the overall shape of the experimental pipeline is U-shaped, which can simulate the water flow at the bend of the existing drainage pipeline, making the simulation of the experimental pipeline more comprehensive. And a support 21 is fixedly installed below the experimental pipeline. A temperature sensor 23 is installed on the side wall of the experimental pipeline. The temperature sensor 23 is electrically connected to the PLC controller. The temperature sensor can monitor the temperature of the water flow in the experimental pipeline. Further, the temperature sensor is arranged behind the tee joint and the influent and infiltration port along the water flow direction for temperature acquisition, and transmits the temperature information to the PLC controller. The experimenter compares the data collected by the temperature sensor with the data collected by the optical fiber to calibrate and debug the sensitivity of the optical fiber test.

[0035] Specifically, the outer peripheral surface of the experimental pipeline is coated with a heat-insulating material. Further, it reduces the influence of the external environment on the water flow and water temperature inside the experimental pipeline. At the same time, it can also simulate the environment where the real drainage pipeline is located.

[0036] Specifically, the simulated damaged water supply tank 4 is connected to the influent infiltration port 20 through a simulated damaged water inlet pipe 6. A second water pump 5 is connected to the main water pipe of the simulated damaged water inlet pipe 6. An influent infiltration control valve 7 is installed on the branch water pipe of the simulated damaged water inlet pipe 6. The influent infiltration control valve 7 is electrically connected to the PLC controller. By controlling the start and stop of the second water pump and the opening and closing degree of the influent infiltration control valve through the PLC controller, the water volume at the damaged point and leakage point of the actual drainage pipe is simulated. Further, the optical fiber measures the influence of the water flow mixed at the influent infiltration port on the water temperature in the experimental pipe. The experimenter compares the temperature monitored by the temperature sensor at the influent infiltration port with the temperature measured by the optical fiber, which is convenient for the experimenter to calibrate and debug the sensitivity of the optical fiber to measure temperature.

[0037] Specifically, the simulated mixed-connection water supply tank 8 is connected to the tee joint 22 through a simulated mixed-connection water inlet pipe 10. A third water pump 9 is connected to the simulated mixed-connection water inlet pipe 10 near the simulated mixed-connection water supply tank 8. A mixed-connection water volume control valve 11 is installed on the simulated mixed-connection water inlet pipe 10 away from the third water pump 9. The mixed-connection water volume control valve 11 is electrically connected to the PLC controller. By controlling the start and stop of the third water pump and the opening and closing degree of the mixed-connection water volume control valve through the PLC controller, the phenomenon of mixed connection in the actual drainage pipe is simulated, and the water volume entering the experimental pipe after mixed connection is controlled. By comparing the water temperature measured by the temperature sensor at the tee joint with the water temperature measured by the optical fiber, it is convenient for the experimenter to calibrate and debug the sensitivity of the optical fiber measurement.

[0038] Specifically, it further includes a water storage tank 12. The overflow port of the heat preservation water tank 1 is connected to the water storage tank 12. The water storage tank 12 is respectively connected to the simulated damaged water supply tank 4 and the simulated mixed-connection water supply tank 8 through a water supply pipe 15. A water supply pump 13 is connected to the water supply pipe 15 near the water storage tank 12. Water supply control valves 14 are respectively installed on the water supply pipe 15 near the simulated damaged water supply tank 4 and the simulated mixed-connection water supply tank 8. The water supply control valves 14 are electrically connected to the PLC controller. After the simulated damaged water supply tank 4 and the simulated mixed-connection water supply tank 8 supply water into the experimental pipe, the experimental pipe returns the water after the experiment to the heat preservation water tank through a drain pipe. When the water level in the heat preservation water tank rises, the water is discharged into the water storage tank through an overflow pipe for storage. When the water levels in the simulated damaged water supply tank 4 and the simulated mixed-connection water supply tank 8 are insufficient, the start and stop of the water supply pump and the opening and closing of the water supply control valves are controlled through the PLC controller, and water is supplied to the simulated damaged water supply tank 4 and the simulated mixed-connection water supply tank 8 through the water supply pipe, which can avoid affecting the water supply and drainage efficiency after the heat preservation water tank is filled with water, and can also avoid the situation that the simulated damaged water supply tank and the simulated mixed-connection water supply tank run out of water, affecting the test effect and dry burning, affecting the service life.

[0039] In addition, a computer is also included. The PLC controller is electrically connected to the computer. The programming technology therein is known and can be implemented by those skilled in the art, so it will not be elaborated herein.

[0040] The working principle of the present utility model

[0041] The heat preservation water tank circulates and supplies hot water to the experimental pipeline. The simulated damaged water supply tank and the simulated mixed-connected water supply tank supply water to the experimental pipeline through the influent infiltration port and the three-way joint respectively. The water temperature at this point after water supply is measured by a temperature sensor, and the measured data is transmitted to the computer. The water temperature measured by the temperature sensor is compared with that measured by the optical fiber temperature measurement component. Through the difference between the water temperatures measured by the temperature sensor and the optical fiber, the noise and detection sensitivity of the operation of the optical fiber temperature measurement component are judged and analyzed, which is convenient for the experimenter to correct and debug the sensitivity of the optical fiber temperature measurement component.

[0042] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device.

[0043] The embodiments described above are only descriptions of the preferred embodiments of the present utility model, and do not limit the scope of the present utility model. Without departing from the design spirit of the present utility model, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present utility model shall fall within the protection scope determined by the claims of the present utility model.

Claims

1. A sensitivity test device for distributed optical fiber temperature measurement in drainage pipes, characterized in that: It includes a heat preservation water tank (1), a first water pump (3), an experimental pipeline, a simulated damaged water supply tank (4), a second water pump (5), a simulated mixed connection water supply tank (8), a third water pump (9), an optical fiber temperature measurement component (16) and a PLC controller. The water outlet of the heat preservation water tank (1) is communicated with the water inlet of the experimental pipeline through a water supply pipe (2), and the first water pump (3) is installed on the water supply pipe (2). The water outlet of the experimental pipeline is communicated with the water inlet of the heat preservation water tank (1) through a drain pipe (24). The simulated damaged water supply tank (4) is communicated with the side wall of the experimental pipeline through the second water pump (5); the simulated mixed connection water supply tank (8) is communicated with a tee joint (22) on the experimental pipeline through the third water pump (9). The optical fiber temperature measurement component (16) includes a light source demodulation device (1601) and an optical fiber (1602). Both ends of the optical fiber (1602) are connected to the light source demodulation device (1601), and the middle part of the optical fiber (1602) is distributed in the experimental pipeline. The heat preservation water tank (1), the first water pump (3), the simulated damaged water supply tank (4), the second water pump (5), the simulated mixed connection water supply tank (8), the third water pump (9), and the optical fiber temperature measurement component (16) are all electrically connected to the PLC controller.

2. The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline according to claim 1, wherein: The heat preservation water tank (1), the simulated damaged water supply tank (4), and the simulated mixed connection water supply tank (8) are all equipped with a display screen and a temperature control device.

3. The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline according to claim 1, characterized in that: The experimental pipeline includes a large-diameter pipe (17), a reducing joint (18), and a small-diameter pipe (19). The large-diameter pipe (17) is communicated with the small-diameter pipe (19) through the reducing joint (18), and the large-diameter pipes (17) are connected through the tee joint (22). It further includes an inflow and infiltration port (20), and the inflow and infiltration port (20) is opened on the side walls of the large-diameter pipe (17) and the small-diameter pipe (19).

4. The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline according to claim 3, characterized in that: The experimental pipeline is integrally U-shaped, and a bracket (21) is fixedly installed below the experimental pipeline. A temperature sensor (23) is installed on the side wall of the experimental pipeline, and the temperature sensor (23) is electrically connected to the PLC controller.

5. The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline according to claim 4, characterized in that: The simulated damaged water supply tank (4) is communicated with the inflow and infiltration port (20) through a simulated damaged water inlet pipe (6), and the second water pump (5) is communicated with the main pipe of the simulated damaged water inlet pipe (6). An inflow and infiltration control valve (7) is installed on the branch pipe of the simulated damaged water inlet pipe (6), and the inflow and infiltration control valve (7) is electrically connected to the PLC controller.

6. The sensitivity test device for distributed optical fiber temperature measurement of a drainage pipeline according to claim 5, wherein: The simulated mixed connection water supply tank (8) is communicated with the tee joint (22) through a simulated mixed connection water inlet pipe (10), and the third water pump (9) is communicated with the simulated mixed connection water inlet pipe (10) near the simulated mixed connection water supply tank (8). A mixed connection water volume control valve (11) is installed on the simulated mixed connection water inlet pipe (10) far from the third water pump (9), and the mixed connection water volume control valve (11) is electrically connected to the PLC controller.

7. A sensitivity test device for distributed optical fiber temperature measurement of a drainage pipe according to claim 6, characterized in that: It further includes a water storage tank (12). The overflow port of the heat preservation water tank (1) is communicated with the water storage tank (12). The water storage tank (12) is respectively communicated with the simulated damaged water supply tank (4) and the simulated mixed connection water supply tank (8) through a water supply pipe (15). A water supply pump (13) is communicated on one side of the water supply pipe (15) close to the water storage tank (12). Water supply control valves (14) are respectively installed on one side of the water supply pipe (15) close to the simulated damaged water supply tank (4) and the simulated mixed connection water supply tank (8). The water supply control valves (14) are electrically connected to the PLC controller.

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