头部主型线变化对列车隧道交会气动性能的影响

Numerical simulation method based on the three-dimensional, compressible, unsteady N-S equations and k-ε double-equation turbulence model was used to study the influence of head outlines on aerodynamic effect of two trains intersecting in a tunnel, and the changes of the side force, resistance force and pressure on tunnel wall were obtained. The results show that the pressure values obtained by the present numerical method are in good agreement with those of the model-scaled test and full-scale experiment, and their relative error is both less than 5%. The aerodynamic effect caused by the single-arched train is slightly better than that of the double-arched train. The outline of head longitudinal section has a large impact on the aerodynamic forces induced by two trains passing by each other in a tunnel. When it changes from concave to convex, the side force amplitude coefficients of head car, the middle car and tail car are increased by 11.2%, 14.0% and 23.7%, respectively, and the maximum total resistance force coefficient is increased by 7.2%. When the outline of head horizontal section changes from the wide shape to the narrow shape, the side force amplitude coefficients of head car, the middle car and tail car are increased by 3.4%, 2.4% and 4.6%, respectively, but the maximum total resistance force coefficient is reduced by 4.0%. The change of head outlines has little effect on the tunnel wall pressure variations, and the maximum difference is 1.7%.