Investigation of train safety domain in cross wind in respect of attitude change

High-speed trains require a lighter weight for speeding up and saving energy; a higher-speed and lighter weight will lead to larger attitude changes for a train travelling in a cross wind, which will threaten its running safety more. This paper presents a new methodology for the assessment on limit safety conditions of High-speed trains subjected to cross wind action while considering the attitude change. The method of defining the stable attitude of a train in cross winds by analysis of fluid-solid coupling vibration is presented. The influence of attitude changes on flow field, aerodynamic loads and running safety of trains is analyzed. The dangerous states and running safeties of a train are analyzed. The safety domain of the train running in cross wind in consideration of the attitude change is defined according to the critical speed of the cross winds of the train running at different speeds. The running safety domain of the train decreases because of changes of aerodynamic loads caused by attitude change. The effect of attitude change on running safety becomes more and more apparent with an increase of train speed and cross wind. Attitude change effects need to be taken into account when calculating aerodynamic loads and the running safety of train.