Recently, reduction of CO_2 emission from automotive is required. In order to reduce CO_2 emission from heavy duty vehicle such as truck and trailer, its drug force in aerodynamics need be improved. In this study, drug force of 1/32-scale truck model attached a wind deflector (various front and rear angles) on its truck container was measured using small-scale wind tunnel. Moreover, the drag force, flow patterns and pressure distributions were calculated by a Computational Fluid Dynamics. As the result, it was confirmed that the drag force could be reduced by wind deflector an attached on the container. That is because it was reduced a size of wake flow and be increased a static pressure behind the truck model.
