Efficient numerical simulation method for three dimensional resin flow in laminated preform during liquid composite molding processes

We propose an efficient simulation method of three-dimensional (3D) resin flow in laminated preform composed of multiple layers with different permeabilities at each layer. Because of the small thickness of each layer, a huge number of nodes are needed for 3D flow simulation if solid elements are adopted and full 3D simulation takes extremely long even by parallel computing. Instead of 3D solid elements, we propose multi-layered shell elements for 3D flow simulation with a short computing time. We describe the numerical formulation of multi-layered shell element method to consider the through-thickness flow as well as the planar flow. The accuracy and efficiency are evaluated by new dimensionless parameters defined in terms of preform permeability ratio and of the ratio of shell element size to the distance between the adjacent layers. Some simulation results are presented to demonstrate the advantages of the multi-layered shell element method for 3D flow simulation. © 2019 Elsevier Lt

In-plane permeability characterization of engineering textiles based on radial flow experiments: A benchmark exercise

International audienceAlthough good progress was made by two international benchmark exercises on in-plane permeability, existing methods have not yet been standardized. This paper presents the results of a third benchmark exercise using in-plane permeability measurement, based on systems applying the radial unsaturated injection method. 19 participants using 20 systems characterized a non-crimp and a woven fabric at three different fiber volume contents, using a commercially available silicone oil as impregnating fluid. They followed a detailed characterization procedure and also completed a questionnaire on their set-up and analysis methods. Excluding outliers (2 of 20), the average coefficient of variation (cv) between the participant’s results was 32% and 44% (non-crimp and woven fabric), while the average cv for individual participants was 8% and 12%, respectively. This indicates statistically significant variations between the measurement systems. Cavity deformation was identified as a major influence, besides fluid pressure/viscosity measurement, textile variations, and data analysis

In-plane permeability characterization of engineering textiles based on radial flow experiments: A benchmark exercise

Although good progress was made by two international benchmark exercises on in-plane permeability, existing methods have not yet been standardized. This paper presents the results of a third benchmark exercise using in-plane permeability measurement, based on systems applying the radial unsaturated injection method. 19 participants using 20 systems characterized a non-crimp and a woven fabric at three different fiber volume contents, using a commercially available silicone oil as impregnating fluid. They followed a detailed characterization procedure and also completed a questionnaire on their set-up and analysis methods. Excluding outliers (2 of 20), the average coefficient of variation (cv) between the participant’s results was 32% and 44% (non-crimp and woven fabric), while the average cv for individual participants was 8% and 12%, respectively. This indicates statistically significant variations between the measurement systems. Cavity deformation was identified as a major influence, besides fluid pressure/viscosity measurement, textile variations, and data analysis