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Computer simulation is helpful for understanding the manufacturing of pultruded advanced composites. This research involves a three-dimensional examination of the temperature and thermochemical aspects for the manufacturing of cartesian fiberglass-epoxy composite materials. Comparison of the computer generated predictions were made with experimentally measured temperature profiles and the degree of cure obtained using a Differential Scanning Calorimeter (DSC). A numerical model employing Patankar's [1] control volume based finite difference technique was employed for solving the governing energy and species equations used to model the entire heating (moving and non-moving) sections of the pultruder. This computer model can be utilized to establish functional relationships between combinations of pull speed, fiber volume, and die temperature profiles and can be employed to refine the pultruder for manufacturing composites, indicating the importance of controlling the processing parameters in producing quality pultruded products. Since this computer simulation is independent of predetermined laboratory values in generating results, it can establish the guidelines in the design of an advanced pultrusion machine itself, and in orchestrating the future development of advanced composite materials.

Injection pultrusion is a continuous process for manufacturing composite materials. To produce good quality parts it is essential that complete wet out of the reinforcement fibers is achieved in the injection chamber. To achieve good wet out of the fibers, the magnitude of the resin injection pressure is extremely important. The present study is focused on the effects of pull speed, fiber volume fraction, resin viscosity and compression ratio (taper) of the injection chamber on resin fiber wet out within the injection chamber for polyester-glass roving composites. The recommended injection pressures for complete wet out are predicted for a wide and comprehensive variety of processing variables; this work is novel in that it has new and comprehensive results not available in the existing literature. Darcy's law is used to model the fiber/resin system of injection pultrusion. The Gutowski [Gutowski, T.G., Morigaki, T. and Cai, Z. (1987). The Consolidation of Laminate Composites, Journal of Composite Materials, 21(7): 172-187.] permeability model is used to determine the transverse permeability and the Kozeny-Carman [Carman, P.C. (1939). Flow Through Granular Beds, Trans. Int. Chem. Eng., 15: 150-166.] model is used to predict the longitudinal permeability. The finite volume method is used to predict the resin pressure field, resin velocity field, and resin moving flow front location.