Stiffness analysis of embedded bushing with stud bolt connection in wind turbine blades

doi:10.19936/j.cnki.2096-8000.20231128.012

Abstract

Abstract: Embedded bushing with stud bolt connection is a major method for root connection and segment joint of large wind turbine blades. Accurate computation of clamped member stiffness is a key issue to ensure the safety design of static and fatigue loads of wind turbine blades. Based on the embedded bushing with stud bolt connection used in a real sectional blade, assuming frustum distribution of the stress field of the hollow cone clamped embedded bushing members, the analytical expression of axial member stiffness could be derived. The finite element method was implemented to determine the suitable conical half-angle. The effects of the bolt diameter, the thickness of the bushing, and the grip length on the axial member stiffness were further studied. By comparing the analytic and numerical solutions, the accuracy of the theoretical expression of axial member stiffness was verified. Member stiffness increases with the diameter of the bolt and the thickness of the embedded bushing but reduces gradually with grip length. The results indicated that the preferable conical half-angle for embedded bushing with stud bolt connection is between 15° and 18°.

Key words: embedded bushing with stud bolt connection, axial stiffness analysis, wind turbine blade, FEM, bolted joint, composites

CLC Number:

TB332

GAO Xiang, YU Guang’an, LIU Zhiqiang, XI Zhenzhao, LIU Fangfang, SONG Xiaofei, QIN Zhiwen. Stiffness analysis of embedded bushing with stud bolt connection in wind turbine blades[J]. COMPOSITES SCIENCE AND ENGINEERING, 2023, 0(11): 90-95.

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