Melt blowing dies are used industrially to produce fine polymer fibers. One type of melt blowing die is the Schwarz die, which consists of several parallel rows of polymer orifices that are surrounded by air inlets. Computational fluid dynamics (CFD) can be used to simulate the flow field from a Schwarz die. In this paper, six different multi-hole die geometries were simulated in 3D, and experimental measurements (from previous work) were used to calibrate the simulation. The flow fields from the multiple jet simulations exhibited significant differences from the flow field of a single jet. For example, the velocity maximums occurred closer to the die face for an array of jets. Furthermore, the spreading rates for the center jets of the multi-hole dies were less than half of the spreading rate of a single annular jet. The jet orifice spacing had a significant effect on how the inside column of jets perturbed the outside jets. The turbulence intensity of all the simulated flow fields did not vary as significantly as the velocity profiles.
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