Hydraulic conductivity and pore sizes of nonwoven filter fabrics

This paper presents a method of determination of hydraulic conductivity and equivalent pore size of nonwoven synthetic filter fabrics. Piwowar's relationship for hydraulic conductivity, checked by Piwowar for glass and basalt fibres is given, and, on the basis of the transformation of Hagen-Poiseuille's formula, values of the empirical coefficients present in these formulae, the investigations on hydraulic conductivity and pore size of nine nonwoven filter fabrics were carried out. The numerical values of these coefficients and, after their substitution, the simplified formulae obtained for hydraulic conductivity and equivalent pore size of nonwoven synthetic filter fabrics are given.