This Small Business Innovation Research Phase I project is directed toward the development and validation of a comprehensive computational model for chemical vapor infiltration (CVI). It involves a macro model that describes the transport processes in a porous preform. The macroscopic properties of the preform that are needed in the macro model are determined from a micro model in which detailed calculations are made for fluid flow, heat transfer, and mass transfer in a generalized unit cell comprising of fibers of rectangular cross section. The technical objectives of the Phase I effort will be to demonstrate the validity of the crucial ingredients of the model for two-dimensional infiltration process. The specific topics to be considered are: (a) validation of the equivalent unit cell approach, (b) evaluation of preform properties as functions of the density, (c) validation of the overall model for a two-dimensional preform by demonstrating that the results of the proposed model compare well with those obtained from full numerical simulation that accounts for all geometric details, and (d) a case study to demonstrate the usefulness of the proposed model as a design/optimization tool. Use of the proposed computational model will lead to lower manufacturing cost and increased use of ceramic composite materials.
