New aerodynamic trucks

Posted on 5 Jan 2011 by The Manufacturer

Nuneaton based engineering company MIRA says it has developed a new design for truck box trailers that has the potential to reduce drag by up to 30%.

Using data gathered from Computational Fluid Dynamics simulation techniques, the company sought to improve the poor aerodynamic performance of a standard 4.5m box trailer – seeking to preserve its load capacity but reduce drag to the levels of a smaller 4m equivalent.

The design was recognised with an award from the Low Carbon Vehicle Partnership in November.

Dr Anthony Baxendale, senior manager for advanced engineering at MIRA, said: “From the outset we wanted to design a solution that recognised the operational considerations of business but still deliver tangible performance gains in financial and environmental terms.

“We used CAD geometry and ‘morphing’ techniques to modify the trailer shape and maximise aerodynamic efficiency without compromising overall load space. We then added under body panels to the cab and trailer to further minimise drag – the result of which was a reduction of up to 30 per cent while avoiding the complex surfacing and space constraints of ‘tear drop’ designs.”

To retain practicality when redesigning the 4.5m trailer, the rear door aperture was reduced only marginally – to the height of a standard 4m box trailer – for ease of loading. Under body panels enable easy access for routine maintenance on brakes and axles and apertures were created in the side skirts to allow for checking of the wheel nuts.

MIRA’s engineers calculate that the reduction in CO2 emissions of between 15 and 20 per cent along with fuel savings means the cost of the adaptations to the trailer could be recouped by fleet operators within 12 months. The enhancements can also be applied to curtain-sided trailers, making it highly commercially viable.

MIRA has previously worked on projects around the world for Truck manufacturers including DAF, Leyland and Hyundai and has created its own Truck Aerodynamic Styling Good Practice Guide. It is now in discussion with a number of potential commercial partners interested in its aerodynamic design.