阅读说明：本技术 一种基于物联网技术的市政管网健康度在线监测系统 (Municipal pipe network health degree on-line monitoring system based on internet of things technology ) 是由 韩成铁 魏绪刚 步春江 龚祚 杨广 鞠凤涛 孙云鹏 刘金桥 于 2020-11-11 设计创作，主要内容包括：基于物联网技术的市政管网健康度在线监测系统,其特征在于市政排水管网外壁环形布设有分布式光纤光栅传感器,用于测量市政污水管道外壁的温度数据；市政管网采取分段控制策略,每400-800米划分一个控制区域,每个控制区域由区域交换机将该区域内分布式光纤光栅传感器检测的温度数据通过光纤环网送至监控中心；监控中心通过分布式光纤光栅传感器检测到的温度数据判断市政排水管网的泄露状况。该系统能够克服传统的人工检测方式和传统传感器存在的诸多不足和限制,具有精确性、稳定性、高效性、高可靠、易组网、及时性、和长期性。(The municipal pipe network health online monitoring system based on the Internet of things technology is characterized in that a distributed fiber bragg grating sensor is annularly distributed on the outer wall of a municipal drainage pipe network and used for measuring temperature data of the outer wall of a municipal sewage pipeline; the municipal pipe network adopts a sectional control strategy, a control area is divided every 400-800 meters, and a regional switch in each control area transmits temperature data detected by the distributed fiber bragg grating sensors in the area to a monitoring center through a fiber ring network; the monitoring center judges the leakage condition of the municipal drainage pipe network according to the temperature data detected by the distributed fiber bragg grating sensors. The system can overcome a plurality of defects and limitations of a traditional manual detection mode and a traditional sensor, and has the advantages of accuracy, stability, high efficiency, high reliability, easiness in networking, timeliness and long-term performance.)

1. An online monitoring system for health degree of a municipal pipe network based on the technology of Internet of things is characterized in that a distributed fiber bragg grating sensor is annularly distributed on the outer wall of a municipal drainage pipe network and used for measuring temperature data of the outer wall of a municipal sewage pipeline; the municipal pipe network adopts a sectional control strategy, a control area is divided every 400-800 meters, and a regional switch in each control area transmits temperature data detected by the distributed fiber bragg grating sensors in the area to a monitoring center through a fiber ring network; the monitoring center judges the leakage condition of the municipal drainage pipe network according to the temperature data detected by the distributed fiber bragg grating sensors.

2. The municipal pipe network health online monitoring system according to claim 1, wherein the distributed optical fiber in the horizontal direction is fixed by using a pipe lifting lug hole or fixed by using the self weight of soil and fixed by using a rubber ring; and the distributed optical fibers in the vertical direction are fixed by utilizing the pipe network interface gaps so as to detect the pipe network leakage condition.

3. The municipal pipe network health online monitoring system of claim 1, wherein a coordinator is arranged in the control area every 50-80 meters, the distributed fiber grating sensors are connected with the area switch through couplers and the coordinator, each coordinator corresponds to one or more couplers, and each coupler corresponds to one or more distributed fiber grating sensors.

Technical Field

The invention relates to the field of relevant monitoring of liquid leakage and pipeline deformation in municipal pipe network pipelines, in particular to an online monitoring system for the health degree of a municipal pipe network based on the technology of Internet of things.

Background

With the rapid development of the economy of China, particularly the accelerated promotion of the urbanization at present, the maintenance management range of the municipal existing pipe network is larger and larger, and the requirement for monitoring the municipal pipe network is higher and higher. Although measures such as maintenance and repair of old pipe networks are gradually promoted in China in recent years, some weak links are unavoidable, and particularly after heavy rain in a short time, serious disasters such as piping and bursting of municipal pipe networks still occur. At present, the monitoring of municipal pipe networks by adopting which mode is one of the problems to be solved urgently.

Traditionally, a municipal pipe network is monitored in a multi-purpose manual monitoring mode, most methods are regular or irregular monitoring, and the method is not only low in efficiency, but also difficult to meet requirements. As for the existing monitoring method, the real-time reaction on the health degree monitoring of the municipal pipe network cannot be realized, and the health degree monitoring can be discovered only when serious damage occurs. The traditional method cannot know the condition of pipeline leakage in real time, so that the phenomena of serious disasters such as municipal pipe piping and even bursting are caused, and the requirements of modern scientific management are not met.

Disclosure of Invention

The invention aims to provide an online municipal pipe network health monitoring system based on the Internet of things technology, which utilizes the advantages of the Internet of things technology and establishes an Internet of things management control open system so as to establish an efficient, stable and safe Internet of things system between Internet of things application and real equipment. The online health monitoring system can comprehensively monitor the leakage condition of the pipe network and the stress strain of the pipeline, and can evaluate the health of the whole life cycle of the pipe network, early warn in time, maintain and replace the related pipe network so as to ensure the basic lives of people.

The technical scheme of the invention is as follows: an online monitoring system for health degree of a municipal pipe network based on the technology of Internet of things is characterized in that a distributed fiber bragg grating sensor is annularly distributed on the outer wall of a municipal drainage pipe network and used for measuring temperature data of the outer wall of a municipal sewage pipeline; the municipal pipe network adopts a sectional control strategy, a control area is divided every 400-800 meters, and a regional switch in each control area transmits temperature data detected by the distributed fiber bragg grating sensors in the area to a monitoring center through a fiber optic ring network; the monitoring center judges the leakage condition of the municipal drainage pipe network according to the temperature data detected by the distributed fiber bragg grating sensors.

Furthermore, the distributed optical fiber in the horizontal direction is fixed by using a pipeline lifting lug hole or fixed by using the self weight of soil and fixed by using a rubber ring so as to detect the leakage condition of a pipe network; the distributed optical fibers in the vertical direction are fixed by utilizing the pipe network interface gaps so as to detect the pipe network leakage condition and the stress strain at the interface.

Furthermore, a coordinator is arranged in the control area every 50-80 meters, the distributed fiber bragg grating sensors are connected with the area switch through couplers and the coordinator, each coordinator corresponds to one or more couplers, and each coupler corresponds to one or more distributed fiber bragg grating sensors.

The accuracy, stability and timeliness of the distributed fiber grating sensing technology are just suitable for the real requirement of municipal pipe network leakage monitoring. The invention utilizes the optical fiber sensing technology, can carry out on-line monitoring on the temperature of the municipal pipe network in the implementation and operation stages, can be used for monitoring the leakage condition of the pipe network by reading the temperature change and the stress strain, can also prevent serious diseases such as piping, bursting, stress strain and the like of the municipal pipe network in advance, and avoids causing more serious loss. The system can overcome a plurality of defects and limitations of a traditional manual detection mode and a traditional sensor, and has the advantages of accuracy, stability, high efficiency, high reliability, easiness in networking, timeliness and long-term performance.

Drawings

FIG. 1 is a system architecture diagram of the present invention.

FIG. 2 is a schematic view of an on-line municipal pipe network health degree detection system, namely leakage monitoring.

Fig. 3 is a schematic diagram of laying a pipeline distributed fiber grating sensor.

Detailed Description

The invention is further illustrated by the following detailed description of a specific embodiment.

1. Scheme design

Adopting N sets of distributed fiber grating sensors: annularly paving a distributed fiber grating sensor 1 on the outer wall 2 of a municipal sewage pipe body; in order to ensure the measurement precision and density, the distributed fiber bragg grating sensor is paved along the outer wall of the pipe body in an adherence manner and used for measuring the temperature change of the outer wall of the municipal sewage pipeline. And the displacement signal output ends and the central wavelength output ends of the N sets of distributed fiber bragg grating sensors 1 are connected with the in-region Internet of things coupler 4 or the controller. And performing edge calculation on the collected signal data through the in-region Internet of things coupler 4 or the controller to obtain the change conditions of the temperature and the stress strain of the outer wall of the municipal sewage pipeline.

2. Method for embedding sensor in site

A. Determining the distribution number and the distribution position of the distributed fiber bragg grating sensors 1, the Internet of things couplers 4 or the controllers in the area according to the maintenance management range of the municipal pipe network to be monitored; the distributed fiber bragg grating sensor 1 is mainly arranged at each interface of a municipal sewage pipe network, an important pipe network, the position of each interface and a position where pipe network settlement may occur; the couplers 4 or controllers of the Internet of things are distributed one by one every 50-80 meters; dividing a control area every 400-800 meters, arranging an area switch 6 in each area, connecting the area switch 6 with the N sets of distributed fiber grating sensors 1 through the coordinator 5 and the coupler 4, sending data detected by the N sets of distributed fiber grating sensors 1 to a monitoring center through a fiber ring network 7 by the area switch 6, and arranging 2 gateways in each area to configure redundant backup.

B. Laying the pre-debugged distributed fiber bragg grating sensor 1 on the outer wall of the municipal sewage pipe body 2 along the wall in the construction stage, and if special needs exist, laying the distributed fiber bragg grating sensor in a high-density centralized manner; the optical fiber in the horizontal direction can be fixed by using a pipeline lifting lug hole or by using the self weight of soil and is protected by using a rubber ring 3 as a backup protection; the optical fibers in the vertical direction can be fixed by utilizing the pipe network interface gap to detect the pipe network leakage and stress strain conditions.

3. Data acquisition, data transmission and data analysis.

The N distributed fiber bragg grating sensors collect real-time temperature and stress strain conditions, transmit the real-time temperature and stress strain conditions to an Internet of things coupler or a controller in an area through optical fibers, perform edge calculation, perform primary processing on collected data and then upload the data to a superior monitoring center. If the system detects the leakage condition, the system reports the leakage position and the condition information to a related information management center and informs related ownership units of maintainers to intervene in advance to process the specific leakage condition so as to ensure the safe and reliable operation of the municipal pipe network.

The health degree online detection optimization algorithm comprises the following steps:

firstly, uploading N fiber bragg grating sensors to an Internet of things coupler or a controller. The pipe network data of the whole city is modeled through a municipal sewage pipe network and a Geographic Information System (GIS), and N fiber arrays are formed through N fiber bragg grating sensors. Based on the system architecture of the internet of things, the whole system can be endowed with the capability of timely adjusting the relevant threshold value of the sensor and processing the bottom layer data.

When the pipe network normally works, the accuracy of the system is influenced by considering that the surface temperature in different seasons can be influenced. Therefore, the municipal pipe network online monitoring system based on the GIS (geographic information system) can timely upload the monitored pipe network pipe wall temperature and stress strain information to the information management center, timely adjust the alarm threshold value, and further improve the reliability and accuracy of the system. When the temperature difference between the temperature and the stress strain value of the monitoring point and the temperature mean value obtained by the nearby fiber grating sensor exceeds a set threshold value, the information management system background immediately receives alarm information, and the background can judge which fiber array and which pipe network have problems through a sewage pipe network positioning algorithm. The calculation method can timely judge the position of the pipe network leakage point, and the system can be in butt joint with an ownership unit management platform to timely send out a work order so as to timely maintain the whole urban pipe network system, thereby ensuring the safe and reliable operation and the online monitoring of the whole life cycle of the municipal pipe network.

According to the invention, the traditional municipal pipe network monitoring system is subjected to networked transformation, and the layout design is carried out on the system architecture. By adopting the technology of the Internet of things and enabling the edge computing technology, the local high-reliability control of field control is realized, and the development guidance of national standards and industrial technological innovation policies is met. The distributed fiber bragg grating sensors are distributed on the outer wall of the municipal pipe network pipe body and connected with the in-region internet of things coupler or the controller, edge calculation is carried out on collected data, real-time effective information is further uploaded to a superior monitoring and management platform, and the requirement on the processing capacity of a superior data center server is further relieved. The system architecture is easy to network, the number of monitoring sensors can be increased or decreased at any time according to actual requirements, but the control strategy of the whole system is zero programmed, and the operation and maintenance threshold is reduced, so that the aim of meeting the actual requirements of engineering is fulfilled.

Related sensors for detecting the health degree of the pipe network and the fiber bragg grating sensors are connected with the in-area internet of things coupler or the controller in a wireless communication mode.

The sensor that is regional to key municipal sewage pipe network lays the requirement:

in the key pipe network area, the fiber grating sensors are arranged at the positions of all interfaces on the outer wall of the municipal drainage pipe network in a key mode, and the distributed fiber grating sensors are arranged at the positions of all the interfaces and possibly at the settlement positions of the pipe network and are used for detecting the pipe network condition of the section of the full life cycle.

The distributed optical fiber in the horizontal direction is fixed by using a pipeline hoisting lug hole or fixed by using the self weight of soil and fixed by using a rubber ring; and the distributed optical fibers in the vertical direction are fixed by utilizing the pipe network interface gaps so as to detect the pipe network leakage condition.

The monitoring principle of the invention is as follows:

distributed temperature measurement principle based on Raman scattering: the distributed optical fiber Raman temperature measuring system is used for measuring temperature based on the temperature effect of Raman scattering light, when laser pulses with certain energy and width are injected into an optical fiber, backward Raman scattering light is continuously generated while the laser pulses are transmitted forwards in the optical fiber, the intensity of the backward Raman scattering light is changed under the influence of the temperature of a scattering point of the optical fiber, the temperature information can be calculated in real time by processing the scattered backward Raman light, and meanwhile, the temperature information is positioned according to the transmission speed of the light in the optical fiber and the time of backward light echo.

When a laser pulse of a certain energy is injected into the optical fiber, raman scattering occurs at a distance L from the injection point, and the relationship between the temperature in the optical fiber and the propagation characteristics of the raman scattered light can be expressed as:

in the formula, P_S，P_ASRespectively representing Stokes Raman scattered light and Anti-Stokes Raman scattered light power; a is_S，a_ASLoss coefficients of the Stokes Raman scattered light and the Anti-Stokes Raman scattered light; l is the length of the optical fiber from the backscattering point to the detection end; l' is a constant temperature T₀The length of the lower calibration fiber; h is the Planck constant; k is Boltzmann constant; and deltav is the variation of the scattering frequency of the signal in the optical fiber.

Based on the pipeline leakage monitoring principle of the distributed optical fiber sensor, a certain temperature difference generally exists between the conveyed liquid and the outside in the conveying process of municipal pipelines such as sewage pipelines, tap water pipelines and the like. When the temperature of the leaking liquid is different from the outside temperature, the temperature field of the surrounding medium will change as a coupled condition occurs in which the leaking liquid transfers heat with the surrounding medium and the leaking liquid diffuses itself. Therefore, the problem of liquid leakage in the pipeline can be converted into the problem of detection of abnormal temperature of the medium around the pipeline. As shown in fig. 2, the monitoring data of the background is monitored, and the field condition is identified according to the abrupt change of the temperature curve of the optical cable.

Based on the principle of the distributed fiber grating sensor, the fiber grating sensor arranged in the annular mode can detect the stress strain of the pipe network, and the stress strain condition of the corresponding municipal pipe network is measured by comparing the change of the central wavelength of the annular optical fiber with the laying condition of the actual pipe network.

The municipal pipe network health degree on-line monitoring system designed by the invention has the following advantages:

accuracy and stability: compared with the traditional manual measurement and the traditional sensor, the optical fiber sensing technology has higher sensitivity and more accurate measurement result; the device is not influenced by electromagnetism or subjective factors of people, and the measurement result is more stable.

High efficiency and timeliness: the distributed optical fibers are embedded in the outer wall of the pipe body of the municipal pipe network and connected with the coupler or the controller of the Internet of things in a wireless communication mode, and the temperature change and stress strain conditions of the pipe network at any moment can be reflected in real time.

High reliability and easy networking: compared with the traditional mode, after the Internet of things technology is adopted, each region is endowed with the edge calculation capability, and local high-reliability control of field control is realized; the number of the devices of the sensors can be increased or decreased more easily through the system architecture of the Internet of things, and the devices are incorporated into the sub-module for detecting the health degree.

Long-term performance: compared with short-term manual monitoring, the optical fiber has longer service life. The pipe network external wall temperature and stress strain monitoring system is placed on the outer wall of a pipe network in a construction stage, can be used for monitoring the temperature and stress strain condition of the outer wall of the municipal pipe network on line, and can also be used for monitoring and evaluating the health state of the pipe network in a later stage operation stage.