风机12.9级叶根螺栓极限及疲劳承载影响因素分析  

Analysis of factors influencing ultimate and fatigue capacity of grade 12.9 root bolts for wind turbine blades

作　　者：罗胜曦 谢东洋 解轲 彭宁 LUO Shengxi;XIE Dongyang;XIE Ke;PENG Ning(China State Shipbuilding Corporation Haizhuang Windpower Co.Ltd.,Chongqing 401120,China)

机构地区：[1]中船海装风电有限公司,重庆401120

出　　处：《华中科技大学学报(自然科学版)》2025年第1期86-91,106,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家重点研发计划资助项目(2022YFB4201103).

摘　　要：为揭示风机叶片12.9级高强度叶根螺栓极限及疲劳承载特性,建立了叶根螺栓预埋螺栓套连接完整有限元模型,分析螺栓自身设计参数缩颈、不同屈服比例的预紧力对叶根极限承载的影响规律,进而研究不同设计参数下螺栓应力范围.搭建12.9级叶根螺栓疲劳试验平台,测试螺栓疲劳等级,突破现有规范对疲劳等级的取值,以及不同参数取值下螺栓的S/N曲线.基于马尔科夫载荷矩阵研究不同S/N曲线、不同设计参数下叶根螺栓疲劳承载的关联关系.结果表明:螺栓施加同一屈服比例的预紧力时,缩颈越大,极限承载能力越高;疲劳载荷过大时,接触面螺栓附近开口出现,弯矩非线性增加,此时缩颈将不能降低螺栓应力范围;螺栓S/N曲线指数取值越大,疲劳损伤越小;若能突破疲劳等级的取值,螺栓设计参数对疲劳损伤的制约将大幅降低.To reveal the limit and fatigue load bearing characteristics of grade 12.9 high-strength root bolts for wind turbine blades,a comprehensive finite element model(FEM)for the connection of pre-embedded bolt sleeves with root bolts was established,and the influence of bolt design parameters such as necking and the preload force at different yield ratios on the ultimate bearing capacity of the blade root was investigated.Subsequently,the stress range of bolts under different design parameters was investigated,and a fatigue test platform for grade 12.9 blade root bolts was constructed to assess the fatigue rating of bolts,broke through existing standards on fatigue level determination,additionally,the S/N curve of bolts was studied under various parameter values.Then,the correlation between fatigue loading of the blade root bolts under different S/N curves and various design parameters was investigated based on the Markov matrix.The research findings indicate that when applying the same preload force with a consistent yield ratio,greater necking results in higher ultimate bearing capacity.When subjected to excessive fatigue loading,the appearance of openings near the bolt contact surface leads to nonlinear increases in bending moment,under such conditions,necking fails to reduce the stress range of the bolts.The higher the exponent value of the bolt's S/N curve,the smaller the fatigue damage.If it′s possible to exceed the value of the fatigue grade,the constraint of bolt design parameters on fatigue damage will be significantly reduced.

关 键 词：叶根螺栓 预埋螺栓套 极限疲劳承载 马尔科夫矩阵 有限元模型 

分 类 号：TB332[一般工业技术—材料科学与工程]