Comparison of wind tunnel tests results on the atm train

Abstract. The paper presents a comparison of the results obtained by experimental campaigns, performed in different wind tunnel plants on the same train model. The comparison will be presented in terms of global forces and pressure distribution on the first vehicle of the train model. Tests have been performed on a flat ground configuration and allow to investigate the effects related to the Reynolds number on the different components of the global aerodynamic force, to the blockage ratio, and to the adoption of open or closed wind tunnel test section. The sharing of the same scaled model and the availability of detailed data regarding the pressure distribution in the different test conditions allow a good insight in the modeling of the train aerodynamics in wind tunnel.. Comparison of wind tunnel tests results on the ATM train by Daniele Rocchi , Martin Schober , Federico Cheli , Alexander Orellano, Gisella Tomasini