Continuous measurement of fiber reinforcement permeability in the thickness direction: Experimental technique and validation

It is an important topic to measure the through-thickness permeability of fiber reinforcements as the resin flow in the thickness direction is widely employed in many composites manufacturing techniques. Continuous techniques for the permeability measurement by simultaneous fabric compaction and liquid flow have been recently proposed as an alternative way to the tedious and laborious conventional permeability measurement techniques. In spite of their efficiencies, these continuous techniques have some limits if the fabric compaction speed or flow rate is relatively great. To address this issue, a new equation for the permeability estimation is proposed. Parametric studies are performed to investigate the influences of the experimental conditions on the validity of the continuous technique. A dimensionless number is proposed as a measure of the relative error of the continuous technique.