Experimental determination of the permeability of engineering textiles: Benchmark II

Abstract

In this second international permeability benchmark, the in-plane permeability values of a carbon fabric were determined by twelve research groups worldwide. One other participant also investigated the deformation of this fabric. The aim of this work was to obtain comparable results in order to make a step toward standardization of permeability measurements of fibrous reinforcements. The procedures used by most participants were according to the guidelines defined for this exercise after the first benchmark. Unidirectional injections in three in-plane directions of the fabric were conducted to determine the unsaturated in-plane permeability tensor. All participants were provided guidelines to the procedure of the experiment to be followed and in addition they were asked to use the same values for parameters such as fiber volume fraction, injection pressure and fluid viscosity to minimize sources of scatter. Unlike benchmark I, results exhibited much less scatter. The scatter between various data obtained correlated to the scatter of the setups themselves. A slightly lower correlation was observed when some parameters differed from the recommended ones.