Clamp-on Ultrasonic Guided Wave Flow Measurement in Thin-walled Pipes

随着气候变化的加剧，水安全变得越来越重要。在英国，每天都有数十亿升水从管网中泄漏。[1，2]因此，政府已为供水公司设定了减少泄漏的目标。由于英国的水管网的状况不太清楚，因此需要增加检测泄漏的能力。[2，3]智能水计量提供了检测泄漏的能力，并告知人们和企业他们的用水模式，使他们能够减少浪费。然而，目前的技术需要切割现有管道，成本昂贵且速度缓慢，阻碍了大规模的推广。在这种情况下，夹持式超声波流量测量是有价值的，因为它是非侵入性的，所以管道可以保持完整，从而减少安装时间和成本。然而，现有的技术不能有效地工作在小的薄壁管，如那些用于家庭供水管道，由于在管壁中的导波的形成。使用沃里克大学[4]开发的新型传感器，在供水管道中普遍存在的15 mm铜管上实现了夹持式流量测量。[5]在发射换能器处的单个五个周期的脉冲串在接收器处产生六个长得多的到达。通过建模和实验，波在系统中的传播的理解已经开发，允许过境时间差流量测量使用所有六个这些到达。目前，正在进行研究，以完善传感器的设计，考虑水中的温度变化，并确定哪种耦合机制最适合传感器的长期安装。用于进行测量和执行流量计算的电子设备被集成到一个低成本、低功耗的微处理器单元中。未来的工作将包括利用机器学习来分析用水模式，实现自动识别泄漏，并生成更直观的信息发送给消费者。[1]大不列颠。德芙拉，（2008年）。英国的水资源战略-未来的水资源。伦敦-环境、食品和农村事务部。[2]大不列颠。国家基础设施委员会，（2018年）。为更干燥的未来做准备-英格兰的水基础设施需求。伦敦--国家基础设施委员会。[3]Bakker，K.（2001年）的第10页。为水付费：英格兰和威尔士的水定价和公平。英国地理学家学会会刊。26（2），143 - 164。[4]放大图片作者：Li，Zhichao，Smith.和狄克逊，史蒂夫M.（2021）微型钳式超声波流量测量传感器的设计。IEEE Sensors Letters，5（6）. [5]史蒂夫狄克逊，2021年。利用超声导波对小直径金属管中流体流动的夹持测量。可在以下网址获得：www.example.com。

With climate change on the rise, water security is becoming ever more important. Billions of litres of water are leaked from the network every single day in England. [1,2] Consequently, water supply companies have been set leak reduction targets by the government. Since the condition of England's water pipe network is not well understood, additional capacity for detecting leaks is required. [2,3] Smart water metering provides ability to detect leaks and inform people and businesses about their water usage patterns, allowing them to reduce wastage. However, current technology requires cutting into existing pipelines which is expensive and slow, inhibiting the rollout on a large scale.Clamp-on ultrasonic flow measurement is valuable in this circumstance as it is non-invasive, so the pipeline can remain in-tact which reduces installation time and costs. However, existing technology does not work effectively on small, thin-walled pipes such as those used in domestic water suppliesdue to the formation of guided waves in the pipe wall. Using novel sensors developed at the University of Warwick [4], clamp-on flow measurement has been achieved on the 15 mm copper pipes that are ubiquitous in water supply plumbing. [5] A single five cycle burst at the transmitting transducer produces six much longer arrivals at the receiver. Via modelling and experiment, an understanding of wave propagation in the system has been developed which allows transit time difference flow measurement to be made using all six of these arrivals. Currently, research is being conducted to refine the design of the transducers, account for temperature changes in the water, and determine which coupling mechanisms work best for long term installation of the sensors. The electronics for making measurements and performing the flow rate calculation are being miniaturised into a low-cost, low-power microprocessor based unit. Future work will include utilising machine learning to analyse water usage patterns, enabling the automaticidentification of leaks and producing more intuitive information to be sent to the consumer about their usage. [1] Great Britain. DEFRA., (2008). Water Strategy for England - Future Water. London - Department for Environment, Food and Rural Affairs.[2] Great Britain. National Infrastructure Commission., (2018). Preparing for a Drier Future - England's Water Infrastructure Needs. London - National Infrastructure Commission.[3] Bakker, K. (2001). Paying for water: water pricing and equity in England and Wales. Transactions of the Institute of British Geographers. 26(2), 143-164.[4] Li, Zhichao, Smith, Luke D. and Dixon, Steve M. (2021) Design of miniature clamp-on ultrasonic flow measurement transducers. IEEE Sensors Letters, 5(6).[5] Steve Dixon, 2021. Clamp-on measurements of fluid flow in small diameter metal pipes using ultrasonic guided waves. Available at: https://dx.doi.org/10.21227/5fr9-6x03.