| Abstract: | Profile development and dimensional change in the melt-spinning process of hollow fibers were studied using a finite element method, and a numerical simulation was compared with experimental results. The numerical simulation of a hollow-fiber spinning process was carried out by considering the changes in inner and outer boundaries. Initial dimensions of inner and outer radii were obtained by measuring the dimensions of extrudate at the extrudate swell point using a capturing device. Extrudate swell plays an important role in determining the initial dimensions of the inner and outer radii, but has less effect on the hollow portion at the die swell point. The effects of spinning variables on the hollow portion show that spinning temperature is the most critical variable in controlling the hollow portion, followed by mass throughput rate. Take-up velocity has relatively less effect. As the mass throughput rate and take-up velocity increase and the spinning temperature decreases, the hollow portion of as-spun fiber increases. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1209–1217, 1998 |
