Study on the Influence of Position Error of Fan Blade Root Bolt on Its Connection Stiffness

Pre-embedded bolt connection is one of the main forms of large wind turbine blade root connection. During the assembly process of blade, the complex stress state caused by position error of blade root bolt leads to decrease in the connection stiffness and produces structural failure. To address the above problems, firstly, the blade root multi-bolt hole positional error model is established; secondly, the influence factors of single high-strength bolt connection stiffness and hole edge stress are analyzed through the Abaqus software; then, the blade root bonding surface stress changes caused by different positional bolt hole errors in the blade root are studied, and the influence law of the radial positional error in the blade root on its connection stiffness is found out; lastly, the effect of the bolt positional error on the connection stiffness of the blade root is simulated. Finally, simulation experiments on the effect of leaf root bolt position error on its connection stiffness are carried out; the results show that the maximum tolerance to meet the leaf root bolt connection stiffness is 0.06 mm, which provides theoretical guidance for the digital manufacturing of blades.