Assessment of structural and transport properties in fibrous C/C composite preforms as digitized by X-ray CMT. Part II : Heat and gas transport
Raw and partially infiltrated carbon-carbon composite preforms have been scanned by high-resolution synchrotron radiation x-ray computerized micro-tomography (CMT). Three-dimensional (3D) high-quality images of the pore space have been produced at two distinct resolutions and have been used for the computation of transport properties: heat conductivity, binary gas diffusivities, Knudsen diffusivities, and viscous flow permeabilities. The computation procedures are based on a double change-of-scale strategy suited to the bimodal nature of pore space, and on the local determination of transport anisotropy. Good agreement has been found between all calculated quantities and experimental data.