Robust Numerical Simulation of Porosity Evolution in Chemical Vapor Infiltration: II. Two-Dimensional Anisotropic Fronts

A mathematical model is developed to study formation and evolution of pores during the chemical vapor infiltration (CVI) process. In this model the evolving fiber–gas interface is described by a level-set function with growth rate determined by the vapor precursor concentration and the local geometry. The vapor precursor, solely driven by diffusion, is described by a boundary value problem of the Laplace equation. We then numerically solve this model using the immersed interface method and a fast searching method developed by the authors for pore detection. This model is able to numerically advance the fiber–gas interface and automatically handle fiber merging and pore formation. Numerical experiments are conducted to validate this model and the corresponding numerical algorithm.