Aerodynamic drag reduction by means of platooning configurations of light commercial vehicles: A flow field analysis

•Experimental investigation of a platoon of 2,3,4 vehicles.•PIV results indicate that the large vortex near the rear base is responsible for the wake pumping.•Platoon marching at small inter vehicle distances can lead to drag reduction as large as 35%.•Low order model to determine the number of vehicles to attain a given drag reduction.