A coupled FEM-FFT concurrent multiscale method for the deformation simulation of CFRPs laminate

Carbon fiber reinforced polymer composites (CFRPs) laminate is increasingly used in aircraft structures and its assembly deformation has great influence on the aircraft aerodynamic profile and mechanical performance. Due to the inherent multiscale nature of CFRPs, the traditional macroscopic models are unable to incorporate their true microstructural details, resulting in them being unable to provide both the macro and micro deformations simultaneously. To address this issue, this work proposed a coupled FEM-FFT concurrent multiscale method for the deformation simulation of CFRPs laminate, where the mechanical response of each macro point of CFRPs laminate was from the corresponding unidirectional representative volume element (UD RVE). The FEM (Finite Element Method) was used for the analysis at the macroscopic scale, while the FFT (Fast Fourier Transform) based method was employed in the UD RVE to speed up the calculation. The elastoplastic behavior of resin matrix in the UD RVE was modelled with the parabolic yield criterion. The proposed concurrent multiscale method was validated respectively by the tension, compression and shearing experiments of CFRPs laminate. The results show that there is a good agreement both for the full strain field and load–displacement curve, demonstrating the effectiveness of the proposed concurrent multiscale method.