Some Studies on Water Permeability of Nonwoven Fabrics

In this paper we report on the water permeability behavior of nonwoven fabrics produced from flax fibers. Three different types of needle punched nonwoven fabrics are produced by varying the depths of needle penetration during the needle punching process. The pore size and its distribution in the nonwoven fabrics are measured by liquid extrusion porometry. Water permeability is measured by the water permeability testing instrument working on the principle of failing hydraulic head method. A finite element analysis is employed to predict the flow velocity through the nonwoven fabrics, A good correlation is achieved between the average velocity data obtained from water permeability test and theoretical prediction based on finite element analysis. The pore size and its distribution play an important role in water permeability characteristics.