Model for Calculating the Mean Temperature on the Friction Area of a Disc Brake

— The calculation scheme for determining the temperature mode of the disc brake taking into account the change of the contour contact area during braking was proposed. For this purpose, the exact solutions of the initial problem of motion and the corresponding heat problem of friction were obtained. On their basis, formulas were obtained in the analytical forms for calculating the evolution of the sliding speed, specific power and work of friction, and the mean temperature on the contact area. The thermal sensitivity of the friction pair materials was taken into account by introducing into the calculation the values of the thermal conductivity and the specific heat capacity at the volumetric temperature. Numerical analysis was performed for a brake with discs made from Termar-ADF carbon composite friction material. The values of such characteristics as speed, braking duration, and maximum and volumetric temperatures, found with and without taking into account the change in the contour contact area, were compared. The performed comparison analysis allowed us to determine the influence the contour friction area has on the evolution of mean temperature during braking. It was found that the level of the temperature calculated with consideration of the friction contour surface increases during braking is higher. Despite the fact that the average contact area is equal and the compared braking processes take place at practically the same time. During analysis, the influence of the change of the apparent contact surface area on the temperature time profile was also examined. It was noticed that a larger apparent area of contact causes a decrease in the value of the maximum temperature achieved and the time of reaching it.