LAUSR

Structural representative volume unit (RVU) has been extensively used to characterize the real effective elastic properties (EEPs) of fiber-reinforced composites (FRCs). The focus of this study is to optimize the optimum mesh size of a multiscale unidirectional RVU (UD-RVU) model to precisely characterize the EEPs of unidirectional FRCs (UD-FRCs). First, a variety of mechanical properties test experiments are carried out to obtain the real EEPs of UD-FRCs for the preparation of the optimization analysis. Then, a microscopic structural UD-RVU is established according to the fiber distribution of the UD-FRCs, and the corresponding ABAQUS/Python code that is used to characterize the EEPs is developed based on asymptotic homogenization theory. Finally, a complete optimization analysis, which is used for balancing simulation time and characterization accuracy, is performed to obtain the optimum mesh size of the multiscale finite element model. The optimized results reveal that the global mesh size of approximately 0.7 μm is the most optimal mesh, which has high accuracy and high simulation efficiency for characterizing the EEPs of UD-FRCs. The maximum error is close to 4.23% compared with experiments, which has a higher precision than the conventional calculation model, and the characterization model is reported in the literature.