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

Lead Research Organisation: University of Warwick
Department Name: Sch of Engineering


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 supplies
due 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 automatic
identification 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.
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Planned Impact

The proposed CDT in NDE will deliver impact (Industrial, Individual and Societal) by progressing research, delivering commercial benefit and training highly employable doctoral-level recruits able to work across industry sectors.

Industry will benefit from this CDT resulting in competitive advantage to the industrial partners where our graduates will be placed and ultimately employed. The global NDE market itself has a value of USD15 billion p.a. [Markets and Markets NDE report January 2017] and is growing at 8% per year. Our partners include 49 companies, such as Airbus, Rolls-Royce, EDF, BAE Systems, SKF and Shell, whose ability to compete relies on NDE research. They will benefit through a doctoral-level workforce that can drive forward industrial challenges such as increased efficiency, safer operation, fewer interruptions to production, reduced wastage, and the ability to support new engineering developments. Our 35 supply chain partners who, for example, manufacture instrumentation or provide testing services and are keen to support the proposed CDT will benefit through graduates with skills that enable them to develop innovative new sensing and imaging techniques and instrumentation. To achieve this impact, all CDT research projects will be co-created with industry with an impact plan built-in to the project. Our EngD students will spend a significant amount of their time working in industry and our PhDs will be encouraged to take up shorter secondments. This exposure of our students to industry will lead to more rapid understanding, for both parties, of the barriers involved in making impact so that plans can be formulated to overcome these.

Individual impact will be significant for the cohorts of students. They will be trained in an extremely relevant knowledge-based field which has a significant demand for new highly skilled doctoral employees. These graduates will rejuvenate an ageing workforce as well as filling the doctoral skills and capability gaps identified by industry during the creation of this CDT. Our industrial partners will be involved in training delivery, e.g. entrepreneurial training to equip our graduates with the skills needed to translate new research into marketed products. Many of the partners are existing collaborators, who have been engaged regularly through the UK Research Centre in NDE (RCNDE), an industry-university collaboration. This has enabled the development of a 5,10 & 20 year vision for research needs across a range of market sectors and the CDT training will focus on these new priorities. Over the duration of the CDT we will actively discuss these priorities with our industry partners to ensure that they are still relevant. This impact will be achieved by a combination co-creation and collaboration on research projects, substantive industrial placements and as well as communication and engagement activities between academic partners and industry. Events aimed at fostering collaboration include an Annual CDT conference, technology transfer workshops, networking events as well as university visits by industrialists and vice versa, forming a close bond between research training and industrial impact. This approach will create lasting impact and ensure that the benefits to students, industry and society are maximised.

Society will benefit from this CDT through the research performed by our CDT graduates that will underpin safety and reliability across a wide range of industries, e.g. aerospace, energy, nuclear, automotive, defence and renewables. As NDE is an underpinning technology it feeds into many of the UK Government's Industrial Strategy Challenge Fund Grand Challenges, for example in energy, robotics, manufacturing and space. It is aligned to the EPSRC prosperity outcomes, e.g. the Productive Nation outcome requires NDE during manufacture to ensure quality and the Resilient Nation requires NDE to ensure reliable infrastructure and energy supplies.


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Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/S023275/1 30/09/2019 30/03/2028
2450136 Studentship EP/S023275/1 18/10/2020 17/10/2024 Luke Smith