Statistical characteristics of out‐of‐plane permeability for plain‐woven structure

Abstract

Since out‐of‐plane permeability of fiber preforms is a function of the number and arrangement of stacked layers, either many layers of preforms or numerous experiments are required to obtain an exact out‐of‐plane permeability experimentally. The reason is that there exist nesting and phase shifting when the preforms are laid up. From a statistical viewpoint, the effect of the number of preform layers on the out‐of‐plane permeability was analyzed by adopting an analytical model proposed in this study. Numerical simulation for a unit‐cell constructed based on geometry of the preform was carried out to validate the analytical model as well as experimental measurements of the permeability. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

Research on permeability of satin fabrics based on fractal theory

“…As long as the position of the flow front at the moment of t, namely (x f , y f ), was known, substitute it into equation (16) and then the primary permeability of the fabrics can be figured out…”

Understanding variability in the permeability of non-crimp fabric composite reinforcements

“…Ngo and Tamma (2004) predicted the through-thickness permeability of a three-dimensional orthogonal woven fabric based on a detailed geometrical description of the textile unit cell, and found qualitative agreement with experimental observations. Song et al (2009) developed a unit cell based model and performed stochastic analyses for the example of a plain weave fabric. These showed that at a given fi bre volume fraction, but different numbers of layers, the average value is constant but the standard deviation decreases with increasing number of layers.…”

Measurement System for On-Line Compaction Monitoring of Textile Reaction to Out-of-Plane Impregnation

“…This is realized by an extremely slight suspension of the lower distribution media, which is moveable. At the beginning of a measurement the distribution media is placed on precisely grounded support discs (14), which allow an exact setting of the pre-compaction. The spring force is so small that even at practically no pre-compaction no movement of the distribution media takes place, prior to the measurement.…”

“…During a saturated measurement a continuous flow through the textile is generated and, according to Eq.1, the pressure drop and the flow velocity (respectively the volume flow rate) are measured. Several of these systems have been developed since 1971 [7][8][9][10][11][12][13][14]. The unsaturated principle requires the monitoring of the flow front progression of a liquid injected into the dry resin.…”