Abstract:
To date, macroscopic analysis methods have been invariably used to analyse textile
composite structures for forming and mechanical performance. Techniques such as
geometric ‘mapping’ for the draping of textile fabrics and classical laminate analysis
combined with simplified failure criteria to determine mechanical performance have
formed the basis of most of these methods. The limited accuracy of the physical laws
applied is appropriate to macro- analysis methods in which the fibre-matrix composite
is treated as homogeneous medium. Today, however, modern high performance
computers are opening new possibilities for composites analysis in which far greater
detail of the composite constituent materials may be made. This paper presents Finite
Elements techniques for the draping simulation of textile composites, specifically
biaxial Non Crimp Fabrics, in which the complex deformation mechanisms of the dry
tows and stitching may be properly modelled at the individual tow and stitch
mesoscopic level. The resulting ‘deformed’ Finite Element model is then used to
provide a basis for accurate simulation of the impregnated composite structure. The
modelling techniques for both draping and structural analysis are presented, together
with validation results for the study of a relatively large scale hemisphere composite
part.
