关键词: 熔喷, 计算流体力学, 熔喷流场, 聚合物拉伸

Abstract:

Melt-blown non-woven fabric has many excellent uses in filtration, bacteria resistance, adsorption, waterproofing and so on, with the potential for a vast future market. The stretching process of polymer to produce melt-blown non-woven fabric is too complex and rapid to be observed experimentally. Therefore, a computational fluid dynamics (CFD) method is widely used in the analysis of this process including the analysis of the flow channels in the dies and the jet flow field under the spinneret. The jet flow field analysis is the most extensively examined, which provides solutions for optimizing the spinneret structures and the jet flow field. This article briefly introduced the principles and characteristics of melt- blowing, and reviewed the research progress of CFD simulations in this area. Currently, the CFD simulations of melt-blowing processes were generally based on airflows in the jet flow field without considering the effect of viscous polymer fibers on them. However, the viscous polymer fibers vibrated under conditions of high velocity and high-temperature airflows, and these effects on the jet flow field should not be neglected. The key problem in melt-blowing was to reduce the diameters of the polymer fibers and improved the quality of the melt-blown non-woven fabric. Consequently, the research should concentrate on the fibers flow field and not the airflow field. The viscous polymer fibers that flow in the melt-blowing process were effected by the high velocity and temperature of the airflows in the jet flow field as the phase was changed from liquid to solid. Although CFD simulations were widely utilized in modeling the melt-blowing process, the study of the flow field simulation of polymer fibers in a molten state had not yet been carried out. This problem remained and should be studied in the future.

Key words: melt-blown, computational fluid dynamics, jet flow field, polymer stretching