Tractor-trailers have a higher drag coefficient than other vehicles due to their bluff-body shape. Numerous add-on devices have been invented to help reduce drag and fuel consumption. The current research extends our previous idea of add-on humps and investigates their effect in conjunction with curved boat-tail flaps. Computational fluid dynamics in the form of unsteady Reynolds-averaged Navier–Stokes and detached-eddy simulations were used to determine viable design strategies. A 3D baseline computational model was constructed using an Ahmed body. Design optimization was applied on the new add-on devices. The results from the optimized design were shown to have a 50.9% reduction in drag coefficient.

Issue Section:
Technical Briefs
Keywords:
agricultural machinery, computational fluid dynamics, drag reduction, fuel, Navier-Stokes equations
Topics:
Boats, Design, Drag (Fluid dynamics), Drag reduction, Simulation, Computational fluid dynamics, Turbulence
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