Gear tooth surface fatigue is one of the most common failure modes of gears. Surface fatigue manifests on two principle phenomena, namely spalling and pitting. Spalls are localized cavities on the teeth surface with relatively important depths, whereas pits are distributed cavities on all the teeth surface with small depths. Generally, spalls and pits appear with nonuniform shapes, making their modelization difficult for researchers. Therefore, common methods assume specific geometries (rectangles, triangles, circles, etc.) to consider surface defects on the gear mesh stiffness evaluation process. In this paper, a new method has been proposed to accurately calculate the gear mesh stiffness of spur gears with surface defects based on the potential energy method. A double discretization of the tooth surface was performed to consider defect depth variation in both width and length directions of the gear tooth. A contact detection algorithm is developed to detect actual contact points during meshing process. Simulation results showed that the deformation of the gear mesh stiffness due to irregular shaped spalls and pits was completely different to those of regular shape and depends on the defect severity. In addition, results showed that the spall size and position have an impact on the final deformation of the gear mesh stiffness. The proposed method allowed remedying to multiple problems exposed by researchers in modeling gear mesh stiffness of gears with tooth surface defects.

齿轮齿表面疲劳是齿轮最常见的故障模式之一。表面疲劳表现为两个主要现象，即剥落和点蚀。剥落是在牙齿表面上具有相对重要深度的局部空腔，而凹坑是在所有牙齿表面上具有较小深度的分布空腔。通常，剥落和凹坑的形状不均匀，这对研究人员来说很难建模。因此，常用方法采用特定的几何形状（矩形，三角形，圆形等）来考虑齿轮啮合刚度评估过程中的表面缺陷。本文提出了一种基于势能法的具有表面缺陷的正齿轮正齿轮刚度的精确计算方法。进行齿面的双重离散化以考虑齿轮齿在宽度和长度方向上的缺陷深度变化。开发了一种接触检测算法，以在啮合过程中检测实际接触点。仿真结果表明，由于不规则形状的剥落和凹坑导致的齿轮啮合刚度的变形与规则形状的完全不同，并且取决于缺陷的严重程度。此外，结果表明，剥落的大小和位置会影响齿轮啮合刚度的最终变形。所提出的方法可以解决研究人员在建模带有齿表面缺陷的齿轮的齿轮啮合刚度时面临的多个问题。开发了一种接触检测算法，以在啮合过程中检测实际接触点。仿真结果表明，由于不规则形状的剥落和凹坑导致的齿轮啮合刚度的变形与规则形状的完全不同，并且取决于缺陷的严重程度。此外，结果表明，剥落的大小和位置会影响齿轮啮合刚度的最终变形。所提出的方法可以解决研究人员在建模带有齿表面缺陷的齿轮的齿轮啮合刚度时面临的多个问题。开发了一种接触检测算法，以在啮合过程中检测实际接触点。仿真结果表明，由于不规则形状的剥落和凹坑导致的齿轮啮合刚度的变形与规则形状的完全不同，并且取决于缺陷的严重程度。此外，结果表明，剥落的大小和位置会影响齿轮啮合刚度的最终变形。所提出的方法可以解决研究人员在建模带有齿表面缺陷的齿轮的齿轮啮合刚度时面临的多个问题。结果表明，剥落的大小和位置对齿轮啮合刚度的最终变形有影响。所提出的方法可以解决研究人员在建模带有齿表面缺陷的齿轮的齿轮啮合刚度时面临的多个问题。结果表明，剥落的大小和位置对齿轮啮合刚度的最终变形有影响。所提出的方法可以解决研究人员在建模带有齿表面缺陷的齿轮的齿轮啮合刚度时面临的多个问题。