In this paper the Fourier series is used to evaluate mode I Stress Intensity Factors (SIF) in three-dimensional planar flaws based on a distortion transformation of a reference disc. Under the hypothesis of an isolated crack, the SIF at each point of the crack border is calculated to assess the crack shape after propagation according to the crack growth rate equation of Paris and Erdogan. The contour is moved along the outward normal to the crack shape. Many examples are proposed with the aim of predicting the final shape of different types of embedded planar flaws.

中文翻译：

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平面三维裂纹的疲劳裂纹扩展

在本文中，傅立叶级数用于基于参考圆盘的变形变换来评估三维平面缺陷中的模式 I 应力强度因子 (SIF)。在孤立裂纹假设下，根据Paris和Erdogan的裂纹扩展速率方程，计算裂纹边界各点的SIF，评估裂纹扩展后的形状。轮廓沿裂纹形状的外法线移动。提出了许多示例，目的是预测不同类型嵌入式平面缺陷的最终形状。