Summary: | 碩士 === 國立臺灣大學 === 工程科學及海洋工程學研究所 === 103 === In this thesis, a complete set of process of dynamic flow-induced resonance analysis is established, through application of large-scale offshore wind turbine blades, which provides industry and academia with a set of method of flow-induced resonance analysis.
First, geometric shape of 3.6-MW and 5-MW large-scale wind turbine blades are designed, plotted. After that, steady flow field analysis is performed to calculate rated power to confirm accuracy of the model.
Second, modal analysis is performed by using finite element analysis software “COMSOL Multiphysics”. Through simulation verification, we confirm accuracy of the simulation compared with references and theory. After that, we study the natural frequency of two blades for different rotor speed, and then study if blades are resonant with operating frequency. Moreover, we perform modal analysis for 5-MW wind turbine tower, and then study if tower is coupled with blade.
Third, wind-induced vibration analysis is performed by using finite element analysis software “COMSOL Multiphysics”, too. Through simulation verification, we confirm accuracy of the simulation compared with references. After that, we choose 6 sections of each blade to calculate Von Karman vortex shedding frequency for normal wind conditions and extreme wind conditions, and then study if blades are resonant with vortex shedding frequency.
Finally, determination and application of wind-induced vibration damage is performed. Through a variety of references, we obtain the range of resonance wind speed for 6 sections of each blade. After that, we select experimental data of the wind speed per second for 2 days, determine whether there is wind-induced vibration damage on blades.
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