Research on the Dynamic Response of High-speed Trains under Different Curve Radii Caused by Wind–sand Flow

To investigate how the curve radius parameter affects the safety of high-speed train operation in a wind–sand environment, researchers used the wind–sand section of the Lanzhou–Urumqi high-speed railway as their research backdrop. The Euler‒Lagrange method was used to discretize the sand particles based on train aerodynamics theory, and the wind–sand flow model of the head–middle–tail three-member formation was established. The accuracy of the model was verified by comparing the data from published papers, and then the train's wind–sand load was calculated and extracted. Subsequently, a dynamic model of a CRH۲ train was created, and the dynamic response of the train was estimated by choosing various curve radii and adding wind–sand loads. The results demonstrated that as wind speed increases, the forces acting on the train due to wind rise. Due to the different shapes and positions of the carriages, the wind–sand load on each car differs; the middle car is subjected to greater lift, lateral force, and overturning moment, as well as lower resistance, nodding moment, and head shaking moment, while the head and tail cars move in the opposite direction and, as a whole, are exposed more adverse forces. The study found that when the curve radius increased from ۷۰۰۰ to ۹۰۰۰ m, the derailment coefficient and wheel-rail lateral force are reduced by approximately ۲۹%~۳۲%, along with an approximately ۲۰%~۲۳% decrease in the wheel load reduction rate. When the radius reaches ۱۰۰۰۰ m, there is a decrease in the derailment coefficient and wheel-rail lateral force of approximately ۵%~۸%, as well as a reduction in the wheel weight load reduction rate of approximately ۳%~۶%.It has been concluded that increasing the curve radius can significantly reduce the safety indices in the wind-blown sand environment, thus improving operational safety. However, it should be noted that a radius of ۸۰۰۰~۹۰۰۰ m is appropriate, and the effect of further increase is not obvious. The results of this study can provide certain guidance for the selection of curve radius and the evaluation of the operational safety of high-speed trains in windy–sandy areas.

کلیدواژه ها:

Lanzhou-Urumqi high-speed railway ، Wind-sand two-phase flow ، Discrete-phase model ، Aerodynamic characteristics ، Dynamic performance