Engineers from the Industrial Noise and Vibration Centre (INVC) have completed two successful projects to reduce noise from fans at a wood burning power plant and an oil refinery in the USA.
INVC’s quiet fan technology – which employs innovative aerodynamic techniques to reduce fan noise at source - has been installed at the Schiller power station in New Hampshire, USA.
A conventional silencer had been fitted to the 3m diameter 1.5MW wood burning boiler fan at the power station to reduce noise disturbance to local residents, but the silencer dramatically reduced the fan’s efficiency, leading Schiller’s engineers to look for an alternative.
INVC’s innovative aerodynamic noise control technology was fitted to the fan. As well as restoring the fan to full efficiency, it eliminated the low frequency tonal noise problem at a fraction of the cost of the original conventional silencer.
The international project was managed remotely from the INVC’s offices in Slough, minimising site visit costs by analysing and interpreting data which was aquired locally in the USA.
INVC Technical Director Peter Wilson said: “The efficiency of fans is often seriously compromised by the silencers that have to be fitted to meet environmental noise requirements.
“Our alternative technology allows our customers to have both stealth and efficiency by introducing innovative aerodynamic techniques to reduce fan noise at source. This means that, in many cases, clients can either dispense with conventional silencers completely or replace them with more efficient and cheaper units.
“The implications for energy consumption and carbon footprints are huge. In the UK alone, it is estimated that if the technology was used in place of silencers on many of the fans for which it is applicable, the total power consumption could be reduced by about 1000 MW.
“We have also recently demonstrated that the technology can be implemented across the world from the UK using our remote analysis facilities to eliminate the necessity for international site visits - a further saving for our customers.”
The work in New Hampshire is not INVC’s only project in the USA. The company’s quiet fan technology has recently been used to reduce the drone from industrial fans at an oil refinery.
Peter Wilson, INVC’s Technical Director, said: “The drone from these five 1.4MW fans – each the size of a house – was causing complaints from the local community so our technology, which eliminates noise at the source rather than masking it, was an ideal solution.
“While the company had looked into the possibility of using traditional silencers, they were aware that these can affect the efficiency of the fans. As they also require a significant capital investment, and incur high installation costs plus the extensive down-time required for installation, they were keen to find a suitable alternative.
“Not only were they impressed by the energy efficiency of our technology, but it also represented a significant capital saving at around 20% of the cost of conventional silencers.”
In a similar project for Corus in the UK, applying the technology to three 4MW fans reduced the capital cost by an estimated £800,000 and saves c£200,000 per annum in running costs compared with conventional silencing.
The technology has been successfully applied to fans ranging in size from the largest industrial centrifugal units down to tiny ejector seat air supply fans a few centimetres in diameter.
