MODELING OF MECHANISMS OF MICROSCOPIC FLOWS OF LIQUIDS IN NONWOVEN FIBROUS STRUCTURES

摘要

Nonwoven fibrous structures contain capillaries of different shapes and sizes formed by fibers arranged at different angles. Liquid droplets in the form of sprays, or bubbles in the form of foams, form films on the fibers which subsequently break to form droplets. These droplets move along the fibers between crossover points and are often pulled to the junction of fibers forming bigger droplets. When the angle between the fibers is small the liquid droplets drawn to the intersection form bow-tie like structures. Chen and Kamath showed that the tendency to form either beads or bow-tie like structures was a function of the angle between the fibers and the surface energy of fibers. In this work we have investigated the behavior of multicomponent liquids and their flows in open capillaries formed by the assemblage of fibers. We have investigated the role of precursor films in the slow spreading of liquids in fibrous structures. We have also investigated the horizontal and vertical spreading of liquids in high-loft nonwovens.