Development of a Novel Spinneret Design for Improved Melt Extrusion Performance: A Computational and Empirical Study

This study presents a comprehensive evaluation of a novel spinneret design to enhance polymer melt extrusion performance in fibre spinning production. Computational fluid dynamics (CFD) simulations using ANSYS Polyflow 2024 R2 are employed to analyse flow behaviour, pressure distribution, and shear profiles within the die. The novel design demonstrates improved flow uniformity, reduced pressure fluctuations, and minimized high-shear regions compared to a baseline spinneret. Experimental validation is conducted through side-by-side extrusion tests using polypropylene and thermoplastic polyurethane, confirming the simulation results. Throughput efficiency tests further reveal that the novel spin pack design significantly reduces residence times by 16% and accelerates purging cycles, indicating fewer polymer stagnation zones and enhanced material changeover efficiency. The computational parametric study conducted on PP shows that the novel design demonstrates improved flow uniformity and a significant reduction in operating pressure, achieving an 11% decrease in die-head pressure compared to the baseline spinneret. Additionally, the optimized geometry successfully minimizes high-shear regions while maintaining a manageable maximum shear rate increase of approximately 19% at the walls, which aids in preventing wall slip. These enhancements lead to lower extrusion pressures and more consistent processing across various polymers. By minimizing material waste and improving process reliability, the new spinneret design contributes to a more sustainable, cost-effective manufacturing process. Overall, these improvements provide a valuable framework for advancing extrusion technologies and optimizing spinneret geometries for high-performance polymer extrusion. The novelty of this work lies in introducing a spinneret geometry specifically optimized to minimize melt residence time, an outcome directly linked to reduced material degradation and waste.