https://popups.uliege.be/esaform21/index.php?id=504 Publications of Auteurs Nahiène Hamila fr 0 https://popups.uliege.be/esaform21/index.php?id=3015 In the aeronautic industry, thicker and more complex composite parts are required. Multi-layered reinforcements are widely used to achieve a certain thickness for the composite part. The tufting technology has become one of the most effective three-dimensional (3D) reinforcement technologies to improve the through-the-thickness mechanical properties of multi-layered reinforcements. A finite element model is proposed for the simulation of tufted reinforcements preforming. The textile reinforcement is modelled by shell elements, and the tufting thread is modelled by bar elements. A specific contact algorithm is developed to manage the interaction between reinforcements and tufting threads. This meso-macroscopic approach reduces the number of finite elements and saves calculation time compared to a mesoscopic model. The model shows a good prediction of deformations during the forming on a hemispherical shape. Fri, 26 Mar 2021 16:50:42 +0100 Fri, 02 Apr 2021 17:07:09 +0200 https://popups.uliege.be/esaform21/index.php?id=3015 https://popups.uliege.be/esaform21/index.php?id=496 During the forming stage in the RTM process, deformations and orientations of yarns at the mesoscopic scale are essential to evaluate mechanical behaviors of final composite products and calculate the permeability of the reinforcement. However, due to the high computational cost, it is very difficult to carry out a mesoscopic draping simulation for the entire reinforcement. In this paper, a macro-meso scale simulation of composite reinforcements is presented in order to predict mesoscopic deformations of the fabric in a reasonable calculation time. The proposed multi-scale method allows linking the macroscopic simulation of the reinforcement with the mesoscopic modelling of the RVE through a macromeso embedded analysis. On the base of macroscopic simulations using a hyperelastic constitutive law of the reinforcement, an embedded mesoscopic geometry is first deduced from the macroscopic simulation of the draping. To overcome the inconvenience of the macro-meso embedded solution which leads to unreal excessive yarn extensions, local mesoscopic simulations based on the embedded analysis are carried out on a single RVE by defining specific boundary conditions. Finally, the multi-scale forming simulations are investigated in comparison with the experimental results, illustrating the efficiency of the proposed approach, in terms of accuracy and CPU time. Sat, 20 Mar 2021 00:05:47 +0100 Fri, 02 Apr 2021 17:00:02 +0200 https://popups.uliege.be/esaform21/index.php?id=496