On the Problem of Assessing the Stability of Freight Train Cars in Crosswind

Study objective. Assessment of the stability of freight train cars in mountainous and transshipment areas under the influence of crosswinds using modern computer modeling methods. Task. Determination of the values of aerodynamic forces and drag coefficients acting on train cars in various wind directions ranging from 0 to 180 degrees, and assessment of the effect of these forces on the margin of stability against tipping, especially in difficult mountainous conditions. Research methods. In Solidworks Flow Simulation software package, an aerodynamic calculation was performed using computer simulation method. Detailed 3D computer models of cars (tank cars, gondola cars, covered cars) have been developed, taking into account their structural elements and geometric dimensions. The obtained aerodynamic results are used in specialized software for calculating the safety margin coefficients of each carriage. The novelty of the work. Quantitative patterns of distributing aerodynamic forces along the length of the train, depending on the angle of the wind flow, are found out. The dependence of the coefficient of aero-dynamic drag on the position of the car in the train (depending on the type of car and the wind direction by more than 2 times) is determined. The effect of accelerating the air flow in the surface layer in mountainous terrain and its effect on the stability of the train is studied. Study results. During the study, the greatest transverse force of the air flow acting on the wind at normal wind direction (900) is determined. In mountainous conditions, the wind speed at the surface can increase by 3 times, creating critical loads. Conclusions. Reducing the speed of the train makes it possible to increase the stability margin to standard values, and the data obtained can be used to optimize train operating modes in difficult weather conditions.