Wind-induced Dynamic Response Of Lattice Towers Using Concrete-filled Steel Tube For Wind Turbines

At present, more and more studies are focusing on the properties of design method andthe stress distribution of lattice tower using Concrete-Filled Steel Tube (CFST) for windturbine, but the issue that the tower structure vibration caused by wind effect whose responseover the tower bearing capacity can make destruction of the wind turbine structure is ignored.Thus the study on wind-induced dynamic response of lattice tower using CFST for windturbine appears particularly important.Based on ANSYS Workbench15.0simulation platform for multi-physics field, thewind-induced dynamic responses of the lattice tower using CFST for wind turbine areanalyzed considering fluid-structure coupling. Details of the study are as follows:(1) According to the specifications and previous research at home and abroad, this paperdiscusses the design method of lattice towers using CFST for wind turbines. By choosing theexample of a practical project of3MW wind turbine, adopting the unified theory of CFST andthe simplified method of space truss, provides the design of the lattice tower using CFST forwind turbine that meets performance requirements and also gives structural design of thelimbs, web members and nodes. Under the condition which the mechanical properties arebasically identical, steel dosage of lattice tower using CFST and the one of tapered cylindricalsteel tower are compared. The result shows that the steel dosage of a lattice tower with threelimbs using CFST for wind turbine reduces by about16%, and it has stronger economy.(2) Establishes whole wind turbine model based on the design, including the latticetower using CFST, blade, hub and nacelle. The whole tapered cylindrical steel tower model isalso established for comparative analysis. By using the Mesh module in the ANSYSWorkbench software, choosing different physical fields due to the fluid and structure, takingthe unstructured grids, mesh generation required by fluid-structure coupling calculation iscompleted.(3) Simulates the steady wind field in the FLUENT software, calculates and analyzes thewind load of the whole wind turbine structure in various running conditions. Based on StaticStructure module, the static behavior of the lattice tower using CFST and tapered cylindricalsteel tower are analyzed and compared after steady fluid-structure coupling. The result shows that the design of a lattice tower with three limbs using CFST for wind turbine is feasible, andit has better mechanical properties.(4) Using UDF in FLUENT software to simulate the gust wind field, wind load of thewhole wind turbine structure under the variable wind speed is calculated and analyzed.Based on Transient Structural module, the dynamic behavior of the lattice tower using CFSTis analyzed using the System Coupling module to realize transient fluid-structure coupling.The results show that lattice tower using CFST for wind turbine meets the designrequirements of strength and deformation in the analysis of wind-induced vibrationresponse.This paper can be read for reference of design and analysis of lattice towers using CFSTfor wind turbines.