Aerodynamic Rear Roof Air Diffuser Don-Bur's aerodynamic air diffuser, designed to fit to rear roof sections, disrupts laminar airflow separating from the roof sheet and reduces the effect of the rear negative pressure pocket.
A Guide to Aerodynamics - How It Affects HGVs Fuel consumption is primarily attributable to 3 things: (1) resistance to inertia, (2) rolling resistance and (3) aerodynamics.