High-order three-scale computational method for dynamic thermo-mechanical problems of composite structures with multiple spatial scales

In this paper, a novel high-order three-scale (HOTS)computational method is presented to analyze the dynamic thermo-mechanical performance of composite structures with multiple spatial scales. The heterogeneities of composite structures are taken into account by periodic distributions of representative unit cells on the mesoscale and microscale. By virtue of multiscale asymptotic analysis, a new unified micro-meso-macro HOTS approximate solutions are successfully constructed for these multiscale problems. Two classes of auxiliary cell functions are established on the mesoscale and microscale, respectively. Also, two kinds of equivalent material parameters are calculated by up-scaling procedure on the mesoscale and microscale, and the homogenization problems are subsequently defined on global structure. Then, the comparisons of approximate performance are obtained in the pointwise sense for the conventional two-scale solutions, low-order three-scale (LOTS)solutions and HOTS solutions, which illustrate the necessity of developing HOTS solutions for simulating the dynamic thermo-mechanical performances of composite structures with multiple spatial scales. Furthermore, the corresponding HOTS numerical algorithm based on finite element method (FEM)and Finite difference method (FDM)is brought forward in details. Finally, some numerical examples are reported to demonstrate the usability of our HOTS computational method to simulate the dynamic thermo-mechanical behaviors of composite structures with multiple spatial scales. This study offers a unified three-scale computational framework that enables the simulation and analysis of dynamic thermo-mechanical problems of composite structures with multiple spatial scales.