Ultimate Bending Capacity of Wind Turbine Tower Structures: A New Empirical Formulation Based on the Geometric and Material Factors

Abstract

Wind energy is emerging as the most promising sustainable energy source due to its abundant resources and environmental benefits. One of the most essential parts of a wind turbine system is the tower, as it is responsible for supporting the weight of the tower top and the loads given by its environment. The preliminary design of the tower section of the wind turbine system is crucial to ensure the system's safety, and a simplified formula is needed to make it more practical. A comprehensive series of ultimate strength analyses on tapered pipes was performed to optimize the tower design, involving the variation and cross-combination of numerous geometric and material parameters. A total of 900 tapered pipe configurations were assessed using finite element method (FEM) analysis via the ABAQUS/CAE program. In the case of tapered cylindrical shells length variations, there was an increase in bending moment from the plastic deformation phase to the critical phase of 29%, 31%, and 39% for pipes measuring 50 m, 30 m, and 10 m, respectively, with the highest ultimate moment of 278.7 kN·m achieved at a pipe length of 50 m. The ultimate bending moment values were then formulated through regression analysis, resulting in a derived formula to predict the ultimate bending capacity of tapered pipes for wind turbine structures. The findings revealed that varying multiple parameters significantly impacted the ultimate strength and critical failure modes of the tapered pipe. The newly developed formula showed good accuracy, providing a reliable tool for design predictions