TÜV SÜD National Engineering Laboratory (NEL) has recently completed the upgrade of its water flow testing facility, funded by the Department for Business, Energy & Industrial Strategy (BEIS) as part of the UK’s national Flow Programme. The new facility will enable global water utility companies and meter manufacturers to assess flow meter performance more accurately, as part of their strategy to deliver more effective, economic and sustainable water management.
Accredited to ISO 17025, the facility’s enhanced digital capabilities offer automated data capture and calculation, as well as process control automation. NEL’s bespoke FlowStudio software enables asynchronous data capture from every instrument, as well as live uncertainty calculation by individual test points, stability monitoring and traceability management.
In addition, NEL’s FlowStudio software acts as a test matrix interface that handshakes with the process control system. This allows it to automatically control pumps, valves, drives etc. to achieve the required stability of flow, temperature and pressure, as well as quickly capture the test point to assess and move on to the next process condition. FlowStudio also provides an automated output table and traceability chain, which deliver much faster test programmes and eliminate the post-processing of data and certificate generation.
The new facility provides a calibration measurement uncertainty of 0.15 % (k=2) on mass flow against the reference meter alone and can be reduced further following planned improvements to the primary gravimetric system. Combined with a remote witnessing capability, NEL’s laboratories can provide a 24/7 operation and quicker turnaround of calibration services, using a test rig audited by UKAS the national body for the accreditation of testing and calibration laboratories.
Carl Wordsworth, Head of Water Sector at TÜV SÜD National Engineering Laboratory, said: “With the current drive for innovation and collaboration in the water industry, having a fully traceable and UKAS accredited water flow facility is incredibly important. The current Ofwat Innovation funding competitions also highlight how vital innovation and collaboration is becoming within the UK Water Industry. This new test facility allows the water industry supply chain the opportunity to test new products on a large-scale test facility which will help to drive innovation and support the UK to become a leader in the development of new technology for the global water industry.”
Broader industry appeal
NEL’s water flow testing facility is also relevant to other industries, such as oil and gas and clean fuels, due to the prevalence of using water as a substitute fluid for flow meter calibrations.
One of the benefits of using water as an analogy for other fluids is that it has very stable properties with a high specific heat capacity, and it is low hazard. By matching the Reynolds number to the ratio of inertial forces to viscous forces, water can be used to predict performance in a range of other fluids. For example, one area of comparison is water against liquid carbon dioxide, an important focus for carbon capture, utilisation and capture (CCUS). Water is also a relevant fluid for the oil and gas industry as ‘produced water’ is extracted alongside hydrocarbons from subsea wells, and its separation and re-injection, or discharge, forms an integral part of the processing strategy.
National standards
Not only does the facility offer customers the opportunity to certify the performance of their devices for technology development and flow research, it also ensures compliance with relevant legislation and industry regulation.
NEL is the Designated Institute for Flow and Density Measurement, under contract from the UK Government’s Department for Business, Energy and Industrial Strategy (BEIS), and part of the UK’s National Measurement System. It is therefore responsible for maintaining the UK’s physical flow measurement standards and, as flow meter technologies are constantly enhanced, it is essential that the uncertainty of the Primary Physical National Flow Standard is sufficiently low enough to validate the performance of new flow meters. NEL’s latest facility upgrade investment, combined with the planned upgrade to the primary gravimetric standard, will improve uncertainty by roughly an order of magnitude, ensuring that the water flow national standard is far enough advanced to stay ahead of industry and societal needs.
The facility allows manufacturers and operators to assess a wide variety of instruments and flow meters such as electromagnetic, ultrasonic and Coriolis mass meters. It has two separate flow lines, covering a wide range of flow rates from 0.1 l/s to 350 l/s. The test sections can be constructed to offer long straight lengths upstream or, if necessary, specific configurations designed to replicate actual installations.
Pipework bends and instrument penetrations into the flow can introduce swirl or an un-even flow profile, which can cause measurement inaccuracy with some meters. NEL, therefore, uses flow conditioner plates to ensure that any unusual flow behaviour is eliminated by evening out the profile to present a symmetrical fully developed turbulent flow at the meter. This ensures that customers have confidence that the flow is fully conditioned.
The re-build is part of a wider programme to refurbish existing flow measurement standards at NEL’s laboratory to address the future needs of flow measurement in the UK.
About TÜV SÜD National Engineering Laboratory www.tuvsud.com/en-gb/nel
The company is a global centre of excellence for flow measurement and fluid flow systems and is the UK’s Designated Institute for Flow and Density Measurement, with responsibility for providing the UK’s physical flow and density measurement standards.