Available from UMI in association with The British Library.; This thesis investigates the air flow around a proposed geometry for a high-speed electromagnetic suspension (EMS) train.; A numerical technique called the panel method has been applied to the representation of the body shape and the prediction of the potential flow and pressure distribution. Two computer programmes have been written, one for a single vehicle in the presence of the ground at different yaw angles, and the second for two-body problems, e.g. a train passing a railway station or a train passing the central part of another train. Two methods based on the momentum integral equations for three-dimensional boundary layer flow have been developed for use with the potential flow analysis; these predict the development of the three-dimensional turbulent boundary layer on the central section (for the analysis of crosswind conditions) and on the nose of the train.; Extensive wind tunnel tests were performed on four models of the high-speed train to measure aerodynamic forces, moments and pressures to establish ground effect characteristics. Flow visualisation showed that the wake vortices were stronger and larger in the presence of a ground. At small yaw angles ground clearance had little effect, but as yaw increased, larger ground clearance led to substantial increase in lift and side force coefficients. The tests also identified the differences between a moving and a fixed ground plane. Data showed that the type of ground simulation was significant only in the separated region.; A comparison of the results predicted using potential flow theory for an EMS train model and the corresponding results from wind tunnel tests indicated good agreement in regions where the flow is attached.; The turbulent boundary layer calculations for the train in a crosswind condition showed that the momentum thickness along the crosswind surface distance co-ordinate increased slowly at the beginning of the development of the boundary layer but then increased sharply at the side top roof on the lee side. The sharp increase is believed to indicate a tendency for flow separation as the solution procedure exhibits signs of failure in this region. (Abstract shortened by UMI.)
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