A new energy-conservative projection method for heterogeneous meshes of electromagnetic-thermal-stress simulations

Multiphysics coupling simulations are of great importance and challenge in engineering and industrial applications. A new efficient full-wave energy-conservative projection method between two heterogeneous meshes is proposed in this article, for the analysis of electromagnetic-thermal-stress coupling in the printed circuit boards (PCBs) and antenna arrays. The projected variables are directly chosen as the electric fields instead of conventional thermal sources, and a scalable domain decomposition method is used to solve the projection problems. In addition, a bounding-box algorithm and the spatial K-dimensional Tree searching algorithm are developed for physical quantity projection between the two heterogeneous meshes. A series of numerical analysis of the electromagnetic-thermal-stress coupling process are conducted. In particular, a realistic PCB example is presented, where 144 CPU cores are used and two heterogeneous meshes of over 20 million grids are constructed. A realistic antenna array with 10 000 units is also presented, where 1200 CPU cores are used and two heterogeneous meshes of over 100 million grids are constructed.