Prediction Model of Brake Drum Temperature on Continuous Downgrade Segments in High-altitude Environment

To study the temperature rise law of the brake drum in the continuous downgrade section of the plateau environment, a theoretical model of the brake drum temperature suitable for the continuous downgrade section of the plateau environment was constructed by introducing the altitude correction coefficient. Using the VBOX 3i as the data acquisition equipment, the Dongfeng Tianlong semi-trailer as the experimental vehicle, the continuous downgrade segments in the Bayan Har Mountain (up to about 4 800 m above sea level) and Ri-yue Mountain (up to about 3 400 m above sea level) on G214 in Qinghai Province as the test sections, by embedding temperature sensors in the brake pad, the relevant parameter data required by the temperature prediction model were collected, such as the slope and length of the test section, the operating speed of the vehicle, the RPM of the diesel engine, the temperature of the diesel engine water tank, and the temperature of brake friction disc and environment. The rolling friction coefficient, heat transfer coefficient and braking force distribution coefficient required by the prediction model were obtained from the experimental data. By comparing the predicted temperature with the measured temperature, the accuracy of the temperature prediction model reaches 94.7%, which verifies the accuracy of the model. The revised brake drum temperature prediction model meets the brake temperature prediction requirements of large trucks at different altitudes, and provides a theoretical basis for the establishment of escape lanes on continuous downgrade sections in plateau areas.