MEASUREMENT OF THE 3-DIMENSIONAL PERMEABILITY OF FIBER PREFORMS USING EMBEDDED FIBER OPTIC SENSORS

An experimental technique is described which can be used to measure simultaneously the three principal permeabilities of fiber preforms made of continuous or short fibers. The technique utilizes embedded optical fibers for detecting the position of the liquid front inside the preform. Expressions were derived for calculating the permeabilities from the three-dimensional measurement of the liquid front. Permeabilities measured by the present fiber optic and by the conventional, pressure drop and dow visualization techniques were compared. Good agreements were found between the results of these techniques.