Numerical calculations of thermal stresses in a railway disk brake at the coupling of temperature, coefficient of friction, velocity, and wear

This article presents a contact 3D thermomechanical finite element model of a railway vehicle disk brake. The distinctive feature of the model is the interdependence of the sliding velocity, coefficient of friction, temperature, contact pressure, and friction material wear, derived from a unified system of equations of heat dynamics of friction and wear. Another important aspect is high geometrical compatibility of the model with physical object. The radial location of the rotation point of the brake pad holder, axis of the mounting plate, and middle of the lining agree with the guidelines of UIC 541-3. All these features allow for a detail study of wear distribution and its further optimization. Based on the recorded experimental data, an analytical form of the coefficient of friction dependent on the sliding velocity and temperature was created. The single braking simulation from initial velocity of 140 km h−1 to a stop, took into account friction material wear based on the generalized Archard's law. The analysis of the results is focused on wear, temperature, contact pressure components of the stress tensor, velocity, and coefficient of friction. The highest average temperature of the six thermocouples was equal to 130.7 °C, while the corresponding calculated value was 128.4 °C.