An experimental characterisation of the wake of a detailed heavy vehicle in cross-wind

Base pressure was shown to reduce with yaw angle, with the low pressure signature of the main lower vortex tilting upwards on the leeward side of the vehicle's base. Total pressure grid measurements showed two different types of wake, those where the stream-wise vortex formed by flow separating off the roof of the trailer is separated from the bulk vehicle wake by a region of high total pressure, and those where the two are indistinguishable. Vehicles without a distinct trailing vortex in this region were found to exhibit stronger horizontal asymmetries in their base pressure profiles.