The flow pattern on the surface of

The flow pattern on the surface of train at different yawangles is performed by the form of surface streamlinesfilled in pressure, sketched in Figure 9. The results revealthat the flow begins to detach from the leading nose tothe tail of the train. As approaching the exposed largeangles, a larger separation angle is apparently observedon the top of the train, which indicates the flow aroundthe train is characterized by three-dimensional structuresthat mainly result from the combination between naturalwind and train-induced wind on the zone of train nose.The flow, blowing over the train nose and detaching fromthe windward roof corner, is deflected along the train axiswith a certain angle. It can be deduced that the larger yawangle mainly dominated by the incoming wind velocity