Mathematical and simulation modelling of normal force for a rail

Description of dynamics occurring during the passage of a rail vehicle is a complex problem, and their mathematical relations are considered in several different aspects such as: interaction of normal force on a beam with fixed and variable cross-section, body, trolley and wheelset displacement and consideration of wheel-rail contact and other phenomena occurring in the contact surface, which include adhesion and creepage. The article presents the effects of work on the issues of normal force at the contact point of the wheel and rail. A mathematical model describing the dynamics of a rail vehicle was defined, determining the normal, transverse and longitudinal force appearing in the wheel-rail contact zone. Variations in the value of the normal force exerted by the wheelset on the rail are the quantity on which the parameters occurring in contact between the wheel and the rail depend. The obtained results from computer simulations show that the normal force is a variable parameter depending on the sign and magnitude of forces occurring between individual blocks of the rail vehicle during the movement. The results obtained will be used in further scientific work devoted to the contact problems.