Abstract. This paper presents methods for calculating the parameters of the porous medium in unidirection-al composite materials (CMs) with various types of regular (hexagonal and tetragonal) and irregular fibrous structures. The porous medium is represented as a system of inter-bundle and intra-bundle pores. These calculation methods can be considered as elements for describing the initial and current structure of CMs when modeling chemical vapor infiltration (CVI) processes of fibrous preforms during the fabrication of composite materials with carbon and ceramic matrices.

Keywords: unidirectional composite material, porous medium modelling, gas-phase processes, hexagonal struc-ture, tetragonal structure, irregular structure

For citation: Nilov A. S., Butorina I. A., Mokhova E. A. Computational determination of parameters of evolv-ing porous media in unidirectional composite materials. Aerospace Engineering and Technology. 2025. Vol. 3, no. 4, pp. 654–671. https://doi.org/10.52467/2949-401X-2026-3-4-654-671; https://elibrary.ru/TIUGLD (In Russian)

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