A Multiphysics Domain Decomposition Method for Transient Electro-Thermo-Mechanical Analysis

This paper presents a novel multiphysics domain decomposition method (DDM) for fully transient electro-thermo-mechanical analysis of complex electronic devices, based on the dual-primal finite element tearing and interconnecting (FETI-DP) framework. The global problem is reduced to a system involving interface and corner degrees of freedom, together with independent subdomain problems, thereby significantly lowering computational complexity. A nodal integration scheme constructs system matrices directly using Vandermonde and differentiation matrices, supporting non-uniform high-order interpolation without Gaussian quadrature. Physics-dependent subdomain partitioning enables tailored discretization for each physical field, enhancing modeling flexibility and algorithmic generality. The method maintains high accuracy in large-scale simulations, supports automatic corner-node selection, and is inherently parallelizable. Several benchmarks validate its accuracy, efficiency, and scalability in simulating challenging transient electro-thermo-mechanical problems.