DEVELOPMENT OF AN EXPERIMENTAL SETUP TO DETERMINE THE PERMEABILITY OF A SINGLE TOW

For the optimization of liquid composite molding processes (LCM), the use of filling simulations is widely spread. In these simulations, the porosity of the dry fibrous textiles is usually represented by a homogenized permeability of the textile on a macroscale. In reality, the flow inside the textile can be divided into the micro flow inside the tows and the macro flow between the tows. However, some flow induced defects such as entrapped air between the tows can only be predicted with simulations on smaller scales. Actually, only few experimental studies on the flow inside a single tow have been published. This micro flow is influenced by capillary effects, whilst the interaction of the injection pressure and capillary effects has not been well examined yet. In this study, a new test setup was developed to determine the permeability of a single tow. It can be used to investigate the flow inside the tow. The results show a good correlation with analytical models for permeability estimation from literature. The test rig allows to validate simulation models for the microflow and to further investigate influencing parameters, such as the capillary effects.