Regional train aerodynamic performance study

With the continuous growth in global energy demand, many industrial sectors are seeking effective strategies to reduce energy consumption. The transport sector is no exception. In railway applications, aerodynamic resistance represents one of the main contributors to energy consumption. Although most railway lines worldwide are dedicated to conventional trains, aerodynamic research has largely focused on high-speed vehicles. This study aims to address this gap by providing a methodology for estimating the aerodynamic resistance of conventional railway vehicles. The approach combines wind tunnel experiments on a scaled model with CFD simulations, enabling the extension of the analysis to full-scale open-air conditions and different train configurations. The results show good agreement between experimental and numerical data, supporting the reliability of the proposed approach. At full scale, the aerodynamic drag is found to be influenced by train configuration, travel direction, and pantograph arrangement. A comparison with running resistance measurements, based on the Davis formulation, indicates that the numerical predictions remain within the experimental uncertainty bounds, with a maximum deviation of approximately 8%. Overall, the study demonstrates that validated CFD simulations can provide reliable estimates of aerodynamic resistance and support design improvements. The results highlight a significant potential for enhancing the aerodynamic performance of conventional railway vehicles, with consequent reductions in energy consumption.