CFD analysis of flow patterns induced by high-speed and freight trains in tunnels and their impact on platform regions
Year: 2026
Type: article
Abstract: This study investigates the aerodynamic slipstream generated by high-speed and freight trains inside tunnels, with a focus on passenger exposure along the platform. Using CFD simulations validated against unique full-scale measurements within railway tunnel, the work compares two train types operating in the same double-track tunnel with platform. Results reveal distinct slipstream topologies: high-speed trains exhibit wake-dominated flow with localized peaks in the near-wake region, while freight trains produce stronger, front-loaded gusts due to flow separation at the locomotive and inter-car gaps. Spatial distributions of longitudinal, lateral, and horizontal velocity maxima are analyzed across multiple platform zones and lateral distances, highlighting the asymmetric exposure patterns between near and far tracks. The study provides new insight into the aerodynamic risks associated with different train designs and demonstrates the utility of CFD in complementing experimental measurements for safety-oriented tunnel and platform assessment. While not a substitute for full statistical analyses, the approach offers valuable flow-based metrics for evaluating local gust intensity and supports infrastructure design choices for mixed traffic rail corridors.
Authors: S. Negri, G. Tomasini, C. E. Araya Reyes, D. Rocchi
Institution: Politecnico di Milano
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7134134119