An improved adaptive finite element method for the simulation of electromagnetic field in PPFDs

Basing on the posteriori error estimation and Superconvergent Patch Recovery (SPR) technology, Elena Zhelezina proposed a fast adaptive mesh refinement strategy which can generate the refined mesh for the required accuracy with only one step of refinement. However, the strategy generates too many elements in PPFDs which is unpractical to simulate the PCBs and IC packages with complicated multiple layers, where the electromagnetic field in PPFDs is calculated, since too many elements lead to the FEM sparse matrices can´t be solved on current machines because of inefficient memory. In this paper, a new formula to estimate the global error is introduced, and then, a new strategy to calculate every element´s refinement degree is presented. Results show that the improved method generates less than half of elements comparing to Elena Zhelezina´s method, but still requires only one step refinement. This mesh refinement strategy was successfully applied to calculate the electromagnetic field in PPFDs for simulating the PCBs and IC packages with high accuracy.