Longitudinal aerodynamic force of vehicles in wind area

In order to determine the number of vehicles using hand brake in the stations of wind area, and to prevent the vehicles runaway, wind tunnel tests and three-dimensional numerical calculation were used to analyze the influence of wind speed, wind direction, wind-break facility and vehicle composition on longitudinal aerodynamic force. The results show that the longitudinal aerodynamic force is proportional to the square of the wind speed, and it is the largest when the wind angle is about 30°. Vehicle composition is different, the longitudinal aerodynamic forces of head car, middle car and end car are approximate, and the maximum relative difference is 4.7%, thus, the number of intermediate cars can be reduced to improve the calculation efficiency. Longitudinal aerodynamic force of vehicle behind wind-break wall is less than that of no wind-break wall, and the protective effect of the concrete wind-break wall is better than the embankment wind-break wall. The results of wind tunnel test and numerical calculation are almost the same. Longitudinal aerodynamic force analysis can provide aerodynamic loads for vehicle anti-slip calculation and determination of the number of vehicles using hand brake.