Fluid flow in coat-hanger die of melt blowing process: comparison of numerical simulations and experimental measurements

The coat-hanger die is an important part in the melt blowing process, the performance of which is characterized by the flow uniformity at its outlet. The primary objective of this study is to validate the finite element method applied in the simulation of fluid flow in the coat-hanger die, so as to search for the optimal flow channel geometry based on simulation and optimization algorithms. The fluid flow in the coat-hanger die is simulated through three-dimensional finite element method in this paper. Simulation results are experimentally verified qualitatively and quantitatively using particle image velocimetry. Good agreements are obtained in the flow patterns and velocities calculated at the die outlet, which suggests that the numerical methodology can reliably predict the details of fluid flow in the coat-hanger die.