采用无奇异边界元法将传统常值面元法中原本直接布置在流体计算域表面网格中心上的奇点移至计算域外部，实现无奇异化.为了分析无奇异边界元法的精度，以类似于经典的圆球绕流为例，对去奇异关键参数进行了详细分析，并将数值模拟结果与文献中解析解进行了对比.研究发现无奇异边界元法可以大幅度提高流场在形状突变处的速度分布精度.
Practice has proved that in the process of numerical analysis, the value of the tangential velocity on the boundary is inaccurate upon comparing the results thereof with frequency solutions by desingularized boundary integral equation method (DBIEM), especially at the place where the normal vector is changed rapidly. In this paper, the singularity of the traditional boundary element method, which is directly arranged in the center of the surface of the fluid computing domain, is moved outside the computational domain using the DBIEM. In order to analyze the accuracy of the DBIEM and validate the above conclusion, three-dimensional uniform flow over sphere has been simulated, and the numerical results are compared with the analytical solutions in the literature. It is found that the velocity accuracy of the flow field can be greatly improved on sudden changed surface shape.
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