Conceptual basis of thermo-controllability in railway braking tribo pairs

Gorbunov, M. I.; Fomin, O. V.; Prosvirova, O. V.; Prokopenko, P. M.

Nowadays, the problem of insufficient braking power is solved by increasing the number of friction pairs, resulting in an increase in resource and labor intensity, unsprung mass, resistance to movement, and low resource efficiency. Also acute is the problem of reducing the noise level when using friction brakes. The analysis of the problems of existing brake equipment led to the choice of a promising direction of research on the effectiveness of braking - control of the temperature of the brake friction surfaces. Purpose. To create a method for increasing the efficiency of the braking system by controlling the cooling of the friction surfaces by adaptive air supply; to create a mathematical model of air pressure supply to the brake frictional contact in order to obtain the optimal diameter of friction lining holes and the air feed rate. Methodology. During the research, the analysis of leading modern studies and patents of technical solutions aimed at improving the frictional properties of brake devices, methods of decision-making theory and expert evaluation of methods for improving the operational characteristics of railway braking systems is conducted. Mathematical modeling of air pressure supply to the zone of relevant frictional contact is applied. Findings. A concept of adaptive energy consumption management at self-ventilation of a brake disc plate using the improved mathematical model which considers geometric parameters of air courses. A method for assessing the influence of the factors on brake equipment operation while supplying the compressed air to the frictional contact is suggested. Originality. The mathematical model of air pressure supply to brake frictional contact is developed in order to obtain the optimal diameter of the friction lining holes. Application of the suggested technique for cooling will allow advancing efficiency of operation of frictional braking elements of rolling stock, increasing the adhesive coefficient, stabilizing the temperature in the tribo-contact, decreasing the wear of brake surfaces of friction and increasing safety of operation. Practical value. As a result of the conducted research complex, the method of adaptive forced cooling of the friction surfaces of the brake was proposed and scientifically substantiated for the first time, which will provide effective characteristics of the cooling process, will allow reducing significantly the dependence of the coefficient of friction on the temperature in the contact zone of the working elements during braking. The application of the proposed developments will allow: using the compressed air, which is drawn from the brake cylinders, effectively; cooling the contact area of "brake pad - wheel", "brake pad - disk", by supplying compressed cooled air into the holes of the brake pad or formation in the contact zone of the active gaseous medium; increasing braking efficiency and reducing the intensity of wear of the brake pads due to the timely removal of friction wear from the contact area; increasing the rail traffic safety by enhancing the reliability of braking.


	Наукова періодика України		Naukovyi visnyk Natsionalnoho Hirnychoho Universytetu