A Simplified Laminar Flow Model for the Pultrusion of Glass Fiber/Polyethylene Terephthalate Commingled Yarns

The pultrusion process is a well‐established and promising technology for the continuous production of high‐performance composite profiles. Accurate modeling of this process, particularly in the heating and cooling zones, is essential for improving product quality, especially in terms of thermal‐field homogeneity and void content. However, existing models often rely on complex multiphysics formulations, such as Brinkman‐based porous‐media approaches describing the polymer matrix flow through the fiber reinforcement, which increases the computational cost. This work presents the development and validation of a simplified and computationally less expensive model for glass fiber/polyethylene terephthalate (GF/PET) commingled‐yarn pultrusion, based on a laminar‐flow formulation combined with an effective homogeneous composite approach. Instead of modeling the polymer matrix separately from the fibers as a flow through a porous medium, the proposed approach identifies an equivalent homogenized material made of matrix and fibers, with effective thermal and rheological properties. Validation is performed by direct comparison with temperature‐field data available in the literature, leading to an error below 5% while reducing computational time by a factor of approximately 3.1. This faster formulation facilitates parametric studies, surrogate‐model development, digital‐twin implementation, and potential industrial real‐time feedback control, process scale‐up, and optimization driven by temperature‐gradient reduction or mass‐flow rate increase.