Study on correlation between permeability and structural parameters of non-crimped fabrics

Abstract

It is a challenge to predict the permeability due to the complex correlation between the permeability and structural parameters of fabric preform. In this paper, the correlation between the in-plane permeability and the structural parameters of the non-crimped fabrics is investigated by using the finite element method. The effect of the intra-ply structural parameters and ply orientations on the in-plane permeability of the fabric preform is investigated. In addition, the influence of four structural parameters on the in-plane permeability is analyzed by the Morris method. The results show that the in-plane permeability is most sensitive to the distance between fiber bundles, while the semi-major axis length of the ellipse section of the fiber bundle is relatively insensitive. The order of the in-plane permeability of non-crimped fabrics preform with different ply orientations is as follows: [0]2 > [0/90] > [−45/45]. The present research is helpful to predict permeability and to further simulate resin filling process.

A study on resin infusion and effects of reinforcement structure at dual scales by a quasi-realistic numerical simulation method

“…Under the condition of creeping flow, the classical Darcy's law can be expressed in the below form where u is the averaged superficial fluid velocity, μ is the viscosity of the fluid, P is the pressure and K is the permeability tensor of the tow. K is a second-order tensor, 18 it can be described as …”

“…where u is the averaged superficial fluid velocity, is the viscosity of the fluid, P is the pressure and K is the permeability tensor of the tow. K is a second-order tensor, 18 it can be described as…”

“…where r is the fiber radius, is the contact angle between the resin and fiber surface, is the directional body angle and D is half of the distance between the fibers. For numerical simulation, the equations governing F st (the force of surface tension), implementing phase field method are described as equations (17) and (18)…”

“…While (N) is the mixing energy density. G is the chemical potential, and it connects equations (17) and (18). @f @; is the source of free energy.…”

Study of Compaction Properties and Permeability Prediction of Multilayered Quadriaxial Non-Crimp Fabric in Liquid Composite Molding Process

“…Specifically, NCF reinforcements are deformed when they are compacted into the mold during the preforming process. For multilayered preforms, the interaction between adjacent fabric layers intensifies and the tows in adjacent fabric layers push each other, which directly affects the global permeability [12,[18][19][20][21][22][23][24][25][26][27]. Therefore, permeability computation methods have related the geometry models to the geometrical perturbations due to deformation.…”