Fluid flow in the coat-hanger die: Validation of the fluid velocity at the die outlet

The melt blowing process has become one of the most important material processing methods due to its ability to produce a wide range of fabrics with a very fine fibrous structure. The design of the coat-hanger die is of the great importance in the melt blowing process, since the quality of the final product depends primarily on the flow homogeneity inside the die. The major objective of this study is to validate the reliability of the computational fluid dynamics technique when computing the velocity field at the die exit. Three-dimensional simulation of the fluid flow in the coat-hanger die was carried out using the Ansys Polyflow. The outcomes of the comprehensive simulation model were verified by the experimental results obtained by Meng et al. (2011). The simulation results showed good agreement with the experimental results of the melt velocity at the die exit. This implies that computational fluid dynamics modelling can accurately predict the behaviour of the polymer melt when properly utilized.