Numerical simulation of densification of carbon/carbon composites by ICVI process

In order to investigate the process of the isothermal chemical vapor infiltration(ICVI) and the distribution of velocity and temperature for fabricating carbon/carbon composites, a multi-physical fields coupling models were developed through COMSOL, including the mass and heat transportation, and the variation of porosity in the densification process. Taking Methane as the precursor, the momentum and energy equations were solved. The results indicate that the temperature rises rapidly to the setting point at the beginning and the distribution of temperature was uniform in the reactor. According to above results, the temperature was set as the constant value in the next step. Then the coupling equations of the mass and momentum conservation and the changing porosity equation were calculated to obtain the variation of preform density. The results show that the region of maximum density is distributed in the middle of preform and this region move towards the edge during the densification process. After the preform is infiltrated for 150h, the bulk density of simulation agrees well with the experimental data, which demonstrate that the densification model is reliable.