Numerical modeling of the mechanical behavior of textile structures on the meso-scale for forming process simulations of composite 3D preforms

Abstract

The models for textile structures based on the Finite Element Method (FEM) are diverse. In general, they can be divided into three groups based on their length scale: macro-, meso-, and micro-scale models. The macro-scale models are the simplest approach and require the least computational cost. On the contrary, the micro-scale models are the most realistic and complex, thus involving extremely high computational costs. The meso-scale models stand in the middle with sufficient representation degree at a reasonable computational cost. Every group of models has its own advantageous application field. For the forming process of 3D preforms, macro-scale models have been widely used. As computational costs drop over time, meso-scale models become more and more favorable. Hence, research efforts increasingly focus on meso-scale models. In this paper, the modeling methods of FEM meso-scale models for plain woven fabric made of glass roving and biaxial reinforced weft-knitted fabric made of carbon fiber/polyamide 6.6 hybrid yarns are introduced. The experimental tests are used to characterize the mechanical properties of the yarns and fabrics. Different modeling methods for the geometries of each type of fabric are described. The mechanical behavior of the models is calibrated and validated with the help of a series of test simulations. Examples for the usage of the introduced models are presented.