Dynamic instability and discomfort of high-speed trains due to aerodynamics in tunnels

Researchers

• Professor Mats Berg (Project leader)
• Dr. Ben Diedrichs
• Siniša Krajnović

Sources of funding

• Banverket/Trafikverket

Research Direction

In this project, high-speed train aerodynamics inside tunnels was mainly studied. Through computational fluid dynamics and multibody vehicle simulations, it has been found that the rear coaches of high-speed trains can start oscillating laterally when negotiating tight and long tunnels. This has also been confirmed in Japanese measurements. The oscillations are annoying and discomforting. Careful design of the train tail geometry can mitigate the discomfort. Crosswind stability of rail vehicles was also studied through simulations and wind tunnel measurements, for instance considering track embankments.

Publications

• Diedrichs B, Krajnovic S and Berg M: On the aerodynamics of car body vibrations of high-speed trains cruising inside tunnels. Journal of Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, Vol. 2, No. 1, pp. 51-75, 2008.
• Diedrichs B, Berg M, Stichel S and Krajnovic S: Vehicle dynamics of a high-speed passenger car due to aerodynamics inside tunnels. Proc. Instn Mech. Engrs, Part F: J. Rail and Rapid Transit, 221 (F4), 527–545, 2007.
• Diedrichs B, Sima M, Orellano A and Tengstrand H: Crosswind stability of a high-speed train on a high embankment. Proc. Instn Mech. Engrs, Part F: J. Rail and Rapid Transit, 221 (F2), 205–225, 2007.
• Diedrichs B: Studies of two aerodynamic effects on high-speed trains: crosswind stability and discomforting car body vibrations inside tunnels. Doctoral Thesis, Report TRITA AVE 2006:81, KTH Rail Vehicles, 2006.
• Diedrichs B, Berg M and Krajnovic S: Large eddy simulations of the flow around high-speed trains cruising inside tunnels. European Congress on Computational Methods in Applied Sciences and Engineering. ECCOMAS. P. Neittaanmäki, T. Rossi, S. Korotov, E. Oñate, J. Périaux, and D. Knörzer (eds.) Jyväskylä, 24–28 July, 2004.
• Diedrichs B, Berg M and Krajnovic S: Large eddy simulations of a typical European high-speed train inside tunnels. SAE 2004-01-0229, 2004.
• Diedrichs B, Ekequist M, Stichel S and Tengstrand H: Quasi-static modelling of wheel–rail reactions due to crosswind effects for various types of high-speed rolling stock. Proc. Instn Mech. Engrs, Part F: J. Rail and Rapid Transit, 218 (F2), 133–148, 2004.
• Diedrichs B: On computational fluid dynamics modelling of crosswind stability for high-speed rolling stock. Proc. Instn Mech. Engrs, Part F: J. Rail and Rapid Transit 217(F3), 203–226, 2003.