The paper gives the results of mathematical modeling of movement of a loaded wagon with elastic suspension under viscous friction force equivalent to the dry friction force. Parameters of vertical relative forced vibrations have been found, which are stipulated by the wave of road irregularity.

The effect of the tailwind on the wagon when it is rolling down from the hump. Study of the movement of the wagon on the profile of the marshalling hump. To provide an incorrect formula for determining the relative velocity and air particles, taken as the absolute velocity of the particles. The article applies the theorem on the addition of velocities in complex motion in vector form. Mathematical substantiated errors in the determination of the specific resistance to movement of the wagon from the air medium and wind, derived from the empirical relationships given the aerodynamic performance of the wagons. The results of the research can be used in the processing of the normative-technical document on the design of hump devices on railways and making adjustments to the dynamics of rolling the wagon in textbooks for universities of railway transport. The results of this study prove the need to revise the practical significance of the formula for finding the specific resistance to the movement of the car from the air and wind in the in the normative-technical document “Rules and regulations for the design of sorting devices on the railways track gauge 1 520 mm ”.

The height of the high-speed section of the sorting slide. Design of high-speed section of the marshalling hump. To prove mathematically the absence of theoretical basis of the formula by which the height of the first profile section of the marshalling hump is calculated in current method of calculation of marshalling humps. The paper uses the theorem on the change of kinetic energy for a non-free material point in the final form, known from theoretical mechanics. The results of the research revealed that the formulas by which the height of the first profile section of the marshalling hump is calculated contradict the theorem on the change of kinetic energy for a non-free material point in the final form. The results of the research can be used in the processing of the normative-technical document on the design of hump devices on railways and making adjustments to the dynamics of rolling the car in textbooks for universities of railway transport. The results of the calculations proved the incorrectness of the derivation of the formula for calculating the height of the first profile section of the marshalling hump in the normative-technical document “Rules and standards for the design of sorting devices on the railways with gauge 1 520 mm”.

In the article, the results of tabular data of previously performed studies of the movement of the car along the descent part of the sorting hump – from its top to the calculated point when exposed to a tailwind of small magnitude are presented in a convenient way for constructing graphical dependencies. For the first time, graphical dependences of acceleration, travel time and rolling speed of the car on the length of the descent part of the hump are constructed.

No abstract