风电齿轮齿根弯曲应力及裂纹特性分析

以风电齿轮为例,利用有限元分析软件ABAQUS,建立了太阳轮简化力学模型,并进行了齿根弯曲应力的分析计算。分析结果与传统计算方法得出的结果基本一致,从而验证了简化模型的正确性。在此基础上,研究了齿轮齿根裂纹特性,分析了初始裂纹长度和外加载荷对应力强度因子(SIF)的影响。结果表明,随着初始裂纹长度的增加,应力强度因子也随之增加,并且应力强度因子与载荷等比例增加。在初始裂纹长度和载荷相同的情况下,应力强度因子KⅠ远大于KⅡ和KⅢ,即在弯曲应力作用下张开型裂纹为风电齿轮轮齿折断失效的主要原因。

Bending stress and crack characteristics at the tooth root of a wind power gear

A simplified model of the sun gear in a wind turbine gearbox is established by finite element analysis software ABAQUS,and the bending stress at the tooth root is calculated. The result is consistent with that obtained by traditional method,and thus validated the simplified model. Based on the result obtained,properties of the crack at the gear tooth root is studied,the influence of initial crack length and load on stress intensity factor( SIF) is analyzed. The results indicate that stress intensity factors increase with initial crack length,and also increase with the load proportionally. With the same initial crack length and load,stress intensity factor KⅠ is much larger than KⅡ and KⅢ,which means that opening mode crack is the main reason of tooth breakage in a wind turbine gearbox.