The quadrilateral surface mesh modification method based on dual cycle operations shows promising advantages in hexahedral mesh generation. However, as only simple cycle eliminations are considered, the existing methods can not handle complex surface meshes. In this study, an improved method based on cycle elimination is proposed for high-quality hexahedral mesh generation from a given quadrilateral mesh. For complex cycles, the dual cycles of a quadrilateral mesh are classified into different types, i.e., concave cycles, flat cycles and convex cycles, and processed accordingly. Then, a novel reversible chord removal operation is proposed to transform the concave cycles into convex cycles. Besides, the interlocked convex cycles are also split to new cycles suitable for elimination with the proposed chord removal operation. After that, the convex cycles can be eliminated. To find the best cycle for elimination, the convex cycles are ranked with geometric and topology information and the cycle with the highest rank is chosen to be eliminated. The above steps repeat until only a hexahedron exists and the final hexahedral mesh can be obtained by reversing the order of the surface modification operations. The effectiveness of the proposed method is validated with dozens of surface meshes.

中文翻译：

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改进了从四边形曲面网格生成六面体网格


基于双循环操作的四边形表面网格修改方法在六面体网格生成中显示出良好的优势。然而，由于只考虑了简单的循环消除，现有的方法无法处理复杂的表面网格。在本研究中，提出了一种基于循环消除的改进方法，用于从给定的四边形网格生成高质量的六面体网格。对于复数循环，四边形网格的双循环分为不同的类型，即凹循环、平循环和凸循环，并进行相应的处理。然后，提出了一种新的可逆和弦去除操作，将凹形环转换为凸形环。此外，互锁的凸循环也被分成适合通过建议的和弦移除操作消除的新循环。之后，可以消除凸循环。为了找到最佳消除循环，使用几何和拓扑信息对凸循环进行排序，并选择排名最高的循环进行消除。重复上述步骤，直到只存在六面体，并且可以通过颠倒表面改性操作的顺序来获得最终的六面体网格。所提出的方法的有效性通过数十个表面网格进行了验证。