Review on melt flow simulations for thermoplastics and their fiber reinforced composites in fused deposition modeling

Fused deposition modeling (FDM) has been one of the most widely used additive manufacturing techniques due to its ease of use and widespread availability. Recent years have witnessed a renaissance of research interest in FDM due to its rapid advances in creating high-performance and industrial-grade parts, e.g., fiber-reinforced polymer composites. Considerable efforts have been made to model the FDM process to reveal the underlying mechanisms that are not yet well understood. This study aims to provide a comprehensive review of recent progress on the melt flow simulations of polymers and their fiber-reinforced composites in FDM. Specifically, analytical and numerical methods for modeling the polymer melt flow in the extrusion and deposition are summarized and discussed. Additionally, the FDM process simulation for short and continuous fiber-reinforced polymer composites as an emerging research field is outlined and discussed. Finally, the outlook of future work on the numerical simulation of FDM is provided.