Aerodynamic Optimization of Freight Wagons and Containers: An Approach for Alternative Design Configurations

Abstract

The design of existing freight wagon fleets gives little consideration to aerodynamics. The entire contour is determined by the laws of traditional steel construction and UIC (International Union of Railways) compatibility also greatly restricts the options for drag reduction in case of the air flow both underneath and along the sides of the vehicles. In terms of wind resistance the freight transportation devices incl. locomotives and containers can be characterized as bluff bodies with their sharp edges and straight vertical surfaces. The high penalty due to their poor aerodynamics provides a lot of potential for any exterior design optimizations. Their velocities can reach 115 km/h with an aerodynamic drag contribution of up to 80 % of the total drag. Expectations to increase the top speed of freight trains up to 160 km/h in near future are forcing the industry to put aerodynamics more in focus whereby safety aspects considering roll, pitch and yaw moments will also play an important role, especially in case the train is exposed to cross-winds. In the framework of the EU-FR8RAIL project, a conceptually new approach offers some options with regard to innovative aerodynamic optimization of single wagons and freight trains in contrast to previous approaches. Within this work it is aimed at investigating exterior geometry of alternative concepts for a single freight wagon with a container.