Improved turbulent flow measurement

Jon Lawson

Investment in dynamic flow testing equipment by Ceramtec has delivered improved analysis of water flow measurements. This breakthrough means that users of water coupled ultrasonic sensors – including utilities companies, industrial process controllers and manufacturers of medical devices – can realise significant benefits.

The new rig, installed at Ceramtec’s Southampton, UK manufacturing facility, measures water flow from 0ºC to 80ºC in a number of environments. The result not only affects the in-house design of ultrasonic sensors, but gives Ceramtec additional data to guide customers on the best combination of sensor and flow tube.

A particular benefit of the investment is the enhanced ability to examine the difference between laminar and turbulent flow – a significant factor in achieving accurate water flow readings, as Ceramtec’s Business Development Manager, Charles Dowling, explained: “The design of flow tubes can actually affect the accuracy of measurement, as friction slows the velocity at the edges of the tube. In laminar flow – which is low flow and consistent – it is hard to measure the variations at the edges because the acoustic beam can’t reach them.

“That isn’t a problem at higher flow, because turbulence is created and flow isn’t localised to any particular point within the tube. That means a greater range of measurements can be taken and averaged out for an accurate overall reading. Therefore, a key aspect of the test rig is to better understand the velocity profile of low flow. We’re looking at designing transducers so the beam covers a bigger area, without being affected by false data – for example, by reflections of the wall of the flow tube. The investment gives us the ability to fine-tune transducers, so customers can achieve more and minimise errors in measurement.”

Ceramtec says that a range of companies will see real benefits, citing more accurate billing in utility meters, precise measurement in medical equipment and improved fuel flow monitoring in automotive, industrial or oil & gas applications.