Revision as of 12:24, 1 July 2024

Abstract

High speed and lightweight are the development trends of high-speed trains in the world. Air braking technology is the last line of defense to ensure the safety and reliability of trains. The complex working environment and huge braking power put forward higher requirements for brake disc configuration and material. Carbon-ceramic composite materials have the characteristics of large specific heat capacity, thermal shock resistance, lightweight and high temperature resistance, and are considered to be high-performance friction materials. By imitating the distribution of animal and plant nutrients transportation pipelines, a carbon-ceramic composite brake disc structure with #-shaped heat dissipation ribs was designed that take into account the anisotropy of the thermal conductivity of carbon-ceramic composite materials. The branched rib structure realizes rapid heat transmission in the disc material, thereby achieving high efficiency and uniform temperature distribution, prevents the concentration of heat generated by friction, which can reduce the maximum temperature value under braking conditions. Then combined with the shape optimization and size optimization design of the local heat dissipation ribs of the brake disc. Further research on the uniform temperature performance and heat dissipation under emergency braking conditions of 400km/h was carried out. The LSR model was used to analyze the different outlet angle, inlet angle and number of the cooling ribs in the same reference flow field. By comprehensively considering parameters as the average maximum temperature, convection heat transfer coefficient, an optimal design that balances cooling efficiency and aerodynamic loss is obtained.