It is possible to verify the performance of a spinneret design by simulating the flow and temperature of the non-Newtonian polymer. The accuracy of the CFD analysis depends on the proper choice of viscosity model for the polymer, along with grading the computational mesh to resolve the thin boundary layers. The analysis reveals the existence of hold-ups, dead spots, recirculations, and high temperature regions.

Further detailed analysis of individual fibers with state of crystallinity is also possible.

Flow pathlines shown inside a spinneret. Contours of pressure are plotted on the hole surfaces near the exit.