Fans, including industrial fans for building air conditioning and power generation applications, consume about 29TWh of electrical energy annually in the UK and this can be associated with approximately 2% of the UK's carbon emissions. Over the last two years PCA Engineers Limited have been leading a project with the objective of reducing power consumption and the associated carbon emissions from cooling fan systems (fan and heat exchanger). The research involved a consortium of manufacturers and other specialists including the European office of ANSYS, Flakt-Woods Limited, The London Fan Company Limited and York International Limited.
The consortium were awarded an applied research grant of £98,000 by the Carbon Trust to help fund this work. The primary motivation was an interest in improving plant efficiency, and all the benefits this brings, through the use of advanced design technology.
Central to the project was the use of computational fluid dynamics (CFD) and using ANSYS CFX 11 the consortium was able to analyse in considerable detail the flow through the complete heat exchanger/fan assembly and to investigate the effect on performance of changes to the fan blade sections.
In this way the group was able to work out what changes to the fans and the heat exchangers would be needed to make the total system more energy efficient. The engineering analysis demonstrated that, by redesigning fans to better match the characteristics of the heat exchanger units to which they are often closely coupled, power consumption and associated carbon emissions could be reduced by 14%.
PCA is currently applying the technology developed for fans during this and other projects to a wider range of engineering components including pumps, axial and centrifugal compressors and turbines.
For more information on the Carbon Trust, please visit http://www.carbontrust.co.uk/appliedresearch.