This study aims to investigate the thermal environment of Carbon-Ceramic (C/C–SiC) brake discs during high-speed emergency braking and assess its impact on surrounding bogie components. A coupled fluid–solid–thermal simulation model, together with full-scale bench testing and thermocouple measurements, was employed to characterize the temperature distribution of brake discs and surrounding air and structural components. Results reveal that the post-braking phase presents the most severe thermal risk, with air temperatures above the axle disc reaching 142.7°C. Under 400 km/h emergency braking, disc temperatures peak at 819–831°C, heating nearby air to 194–209°C at 50 mm distance. Operational risks are identified through measured temperatures of 160°C on critical components, with analysis indicating potential peak exposures reaching 230°C. Critically, the thermal response of the surrounding environment is weakly and non-linearly correlated with distance and highly dependent on measurement methodology. These findings provide bench-based engineering guidance for component layout, suggesting minimum safety clearances of 100 mm for standard components and 200 mm for temperature-sensitive materials. By clarifying the heat dissipation characteristics of C/C–SiC brake discs across the full speed range, this study establishes a validated assessment methodology and offers practical guidance for thermal safety management in high-speed train bogies and other high-speed friction braking applications.
Zheng et al. (Fri,) studied this question.