Multi-degree-of-freedom aerodynamic self-excited forces model of a high-speed maglev train on guideways

The high-speed maglev train has good running stability and ride comfort. It shows broad development prospects and is advancing toward speeds of 600 km/h and above. Under high-speed operating conditions, in addition to static wind loads, the aerodynamic self-excited forces induced by fluid–structure interaction cannot be neglected. This work first establishes a computational fluid dynamics model of the coupled train–guideway system with a geometric scale ratio of 1:28, and verifies the numerical model using wind tunnel tests. Forced vibrations are then applied at different operating speeds to calculate and identify aerodynamic self-excited forces in five degrees of freedom: vertical, lateral, roll, pitch, and yaw. The time-integration characteristics of these forces are analyzed to quantify the contribution of single-degree-of-freedom motion to the remaining degrees of freedom. A five-degree-of-freedom aerodynamic self-excited force model of the high-speed maglev train is then established. These results show that aerodynamic self-excited effects are particularly significant in the vertical, pitch, and yaw degrees of freedom, and the identified aerodynamic derivatives exhibit a clear dependence on the train operating speed. For the self-excited force model, taking the vertical degree of freedom as an example, the aerodynamic lift induced by the vertical displacement and velocity accounts for the highest proportion among all degrees of freedom, reaching up to 87%, and constitutes a major component of the aerodynamic lift. These findings provide a new technical approach for aerodynamic performance evaluation and vibration control of high-speed maglev trains.