Methods for Reducing Aerodynamic Drag on Cargo Carrying Railcars

In recent years the cost of diesel fuel has increased sharply and this has led to an interest in reducing shipping costs by train. Current manufacturing practices of railcars provide an opportunity for research in methods that reduce the aerodynamic drag. This paper reports on a study which involved collecting experimental data from wind tunnel tests using 1/29 scale train models. Two cargo carrying railcar types were studied. The first were coal carrying railcars and the second were auto carrying railcars. Different features of the railcars were investigated. The largest contributor to drag on the coal cars is the large void space of an empty car. The research investigates several roof structures that cover this space and act to reduce drag. From these structures it is determined that the drag can potentially be reduced by nominally 46%. Similarly, profile features of the auto carrying railcars are also investigated. This research reviewed the roof structure, side panels and chassis structure. From the data, it was determined that drag could be reduced by modifying or covering the roof, side panels and chassis structure by nominally 20%, 5% and 15% respectively.