Thermoelastic analysis of carbon/carbon composite brake disks

Abstract

This paper presents a modeling analysis of transient thermoelastic effective investigation of the transient thermoelastic analysis to investigate the thermoelastic behaviors in Carbon/Carbon composite brake system. Aircraft brake systems are usually composed of multiple disks and are subjected to considerable thermal loading by the frictional heat. The heat problem concerning frictional heat and the elastic problem dealing thermomechanical deformation are coupled each other with brake contact problem. Therefore, the coupled heat equation and elastic equation including the contact conditions should be solved simultaneously. The coupled heat and elastic analysis was done using the finite element method differently from other previous researches. Also, the fully implicit transient scheme for the thermoelastic analysis was implemented to improve the accuracy of calculations at every time step. Since the heat capacity of Carbon/Carbon composite is very large, the high temperature of the brake disk system was confined to only the narrow regions near friction surfaces. Therefore, Carbon/Carbon composite brake disk system had little dependence on the thermal boundary conditions of the system. The composite multiple brake disk system showed the larger contact region of the friction surfaces than the elastically isotropic brakes, the more smoothly heat flows through the contact interfaces. The more uniform and lower temperatures and the milder pressure distribution along the friction surface was caused than the elastically isotropic brake system. Carbon/Carbon composite brake disks have excellent thermal characteristics as a brake friction material with the comparison of the isotropic metal brake disk system. The effects of material properties on the thermoelastic behaviors in Carbon/Carbon composite brake disks were investigated to facilitate conceptual designs of the brake system. The maximum temperature history and the global contact ratio were selected as criteria t...