Semi-empirical model of internal pressure for a high-speed train under the excitation of tunnel pressure waves

Abstract

To study the transmission of air pressure from external to internal carriage of high-speed trains, an internal pressure model excited by tunnel pressure wave is established. Firstly, factors affecting the air pressure transmission are analysed. Then, the semi-empirical models of the internal pressure caused by a single factor are established based on both the theoretical analysis and experimental data: (1) by applying the finite element method, effects of carbody deformation are studied; (2) based on the static air tightness test, the transmission from the gaps is modelled and (3) the model of the air ducts are surveyed on the base of the characteristics of the ventilation fans and valves. Finally, three routes are comprehensively considered and a coupling model of the internal pressure is established. Simulation results shows the model is adaptable in predicting the internal pressure under excitation of tunnel pressure waves. Besides, the effect of the factors on internal pressure are studied based on the models. Among the factors, the deformation has the least effect. Meanwhile, the air ducts are the dominant factor that affects the internal pressure at high opening degree, while the gaps will become the dominant factor when the opening degree of air ducts is relatively low.