Automated procedures for the computational modeling of 3D woven composites: From generated models to image exploitation

Numerical prediction of woven composites mechanical properties has been a challenge since decades. Accurate prediction of these mechanical properties lies in the fidelity of the numerical geometries with respect to the real composite microstructure. There are many methods for woven composite geometry generation but they are mostly limited by the residual interpenetrations between yarns which prevent from a discretization conform to the yarns geometries. In a first step of the present research, an automated method for 3D complex woven composites generator is developed. The generation procedure consists of defining an initial situation of yarns made by discretized straight lines with a polygonal cross section attached to each node. A straightening operation consisting of progressive nodal displacement iteratively with a contact management operation is used until the yarns reach their equilibrium position in the RVE. There could remain some minor residual interpenetrations in the obtained RVEs, so a level set based post-processing tool is used systematically after the generation process to suppress the residual interpenetrations, control the yarns volume fractions and insert a thin gap between the yarns for a further discretization conform to the yarns geometry. The discretization tool used subsequently to the geometry generation process uses the analogy to truss structures to generate a high quality tetrahedral mesh for finite elements simulations. Woven composites geometries can also be obtained by exploiting the 3D images of μCT scans. Voxel-based discretizations obtained from image segmentation are nowadays more and more used straightforwardly for mechanical simulations of the behavior of woven composites. The main advantage of this discretization technique is to generate fast regular hexahedral meshes without interpenetrations, that allows producing accurate homogenized elastic properties with acceptable voxel sizes. However, the use of voxel geometries may be que
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished