Quality-improved local refinement of tetrahedral mesh based on element-wise refinement switching

This paper presents an effective sliver-free and quality-improved local refinement algorithm of a tetrahedral mesh for an adaptive solution strategy. The method proposed is composed of controlled local refinement and a conventional quality improvement process. The new feature of the proposed method is the introduction of element-wise refinement switching between longest side bisection and octasection, to boost the quality improvement process of face swapping and node relaxation. Numerical results show that this refinement switching plays a critical role in improving the quality of poorly shaped elements while preserving the quality of well-shaped elements. The results also show that the proposed method is more effective than the previously known methods, considering both the average and minimum quality.