Abstract: The static and transient dynamics of the whole process of tower dismantling are investigated for the stability issues of the tower dismantling process of wind turbines. The first section of the tower of a2 MW wind turbine is taken as the object of study, and the effects of the position of the hook, the number of slings are considered, and the role of the wind load is considered to explore the reasonable configuration of the tower dismantling program. In this study, the displacement and stress response characteristics of the tower drum under different hook positions and the number of slings are firstly solved by using finite element static analysis. Furthermore, the dynamic characteristics of the whole process of lifting the tower drum with three slings are investigated based on the results of the static analysis. The results show that, in the static analysis, the equivalent force of the tower tube with 3 slings is smaller than that with 2 and 4 slings, while also exhibiting the smallest variation of the equivalent force. The deformation response of the tower tube with 3 and 4 slings has similar variation and trend. Under the consideration of wind load and tower inertia force, the maximum deformation and equivalent force of the tower occur during the acceleration stage of lifting. Additionally, as the hook position moves closer to the top flange of the tower section, the variation amplitude of deformation and equivalent stress increases, demonstrating a strong correlation between hook position and tower section acceleration. The maximum equivalent stress during the accelerated lifting phase reaches 223.26 MPa, which is still a large margin compared with the permissible stress of 313.6 MPa in the tower.

Key words: tower, disassemble, statics analysis, dynamics analysis