Aerodynamic Optimisation of HGVs Trailers to Minimise Drag

Abstract

In recent years, increasing efforts have been seen to reduce the output of greenhouse gas emissions. Rising fuel prices and legislative pressure by the UK government has pushed the drive to reducing emission production within the transport industry and, as a result, it has quickly become one of its primary goals. This has prompted the development of drag reduction methods to minimise the fuel consumption within vehicles. While sectors like automotives and aviation have advanced in this area, heavy goods vehicles have lagged behind despite their major contribution to UK freight and greenhouse gas emissions. Research shows that aerodynamic drag accounts for a major portion of HGV fuel consumption, which adds to their operational costs. This study focuses on this field, where boattails of varying slant angles and a teardrop trailer design were investigated, and their effectiveness in reducing drag was evaluated. This investigation was conducted through the use of Computational fluid dynamics where various meshing and modelling procedures were reviewed leading to high fidelity within the simulations. Following the investigation, it was found that the Teardrop trailer showed the best performance where it was able to achieve a 20.34% reduction in drag without any compromise on cargo space. This was attributed with its ability to reduce the size of the trailer base wake, reduce the front to rear pressure differential and faster flow recovery past the wake.