Numerical study on effective thermal conductivities of plain woven C/SiC composites with considering pores in interlaced woven yarns

•Structures of plain woven C/SiC composites are reconstructed at three scale levels.•A numerical model is proposed to predict thermal conductivities of the composites.•The in-yarn and out-of-yarn porosities are fully considered in the model.•Thermal conductivities with various fiber volume fractions and porosities are obtained.