離岸風機新穎桁架式支撐結構之設計分析與驗證

Novel Jacket Structure of Offshore Wind Turbines: Design, Analysis, and Experiment

林育鴻(Yu-Hung Lin)

指導教授 ： 林輝政

共同指導教授 ： 黃心豪(Hsin-Haou Huang)

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01592

摘要

離岸風力發電塔架的支撐結構分為數種，主要依據水深以及海床土壤狀況而定，目前全世界風力發電的需求量不斷提升，所以越來越多離岸風力發電塔架也往更深的海域發展。目前較多的離岸風力發電都集中在水深25-50公尺之間，主要的支撐結構以單樁式為主，但是很多國家已經開始針對桁架式支撐結構進行研究與建設，故本研究的目的是希望針對台灣離岸風況還有海況去對5MW桁架式支撐結構進行設計、分析和驗證，希望可以藉此改善並提升台灣離岸風力發電的效率。
本研究參考了很多桁架式支撐結構相關的文獻後，針對目前現有的桁架式支撐結構進行改良，並自行設計出新型的三腳桁架式支撐結構。本文一共設計了14種支撐結構模型，這些模型的建構是使用SOLIDWORK工程繪圖軟體。而數值模擬分析的部分則是使用ABAQUS有限元素分析軟體。本文的數值模擬是針對建構出來的支撐結構模型進行梁元素分析，薄殼元素分析以及挫曲分析。
實驗部分是利用拉伸試驗機對縮小尺寸的試體進行載荷-位移曲線的量測，一共有2部分的實驗，第1部分是進行實心結構的挫曲實驗，試體的部分是採用自行設計出的新型三腳桁架式支撐結構。第2部分是進行空心結構的挫曲實驗，試體部分是採用圓柱狀空心鋼管結構。最後再將這2個實驗結果與數值模擬進行比對，驗證模擬數據的準確性。
由梁元素與薄殼元素分析的結果可看出本文自行設計出來的0°新型三腳桁架式支撐結構在相同負載狀況下會比其他桁架式支撐結構承受較小的應力，而挫曲分析的結果則顯示90°新型三腳桁架式支撐結構是4種新型三腳桁架式支撐結構中最好的。另外，從模型設計的角度上來探討，新型三腳桁架式支撐結構的桿件數量以及焊接點數量都是遠低於現在普遍使用的傳統四腳桁架式支撐結構，這可以減少施工上的麻煩也可以剩下不少的建構成本。

關鍵字

離岸風力發電機塔架 ； 桁架式支撐結構 ； ABAQUS ； 有限元素分析 ； 挫曲分析

並列摘要

There are several types of support structure in offshore wind turbine tower. How to choose them depends on water depth and soil situation of sea bed. Nowadays the demand of wind energy is increasing, so the development of offshore wind turbine has further expanded to deeper water depth region. Large fraction of wind turbine towers is built on the sea bed where the water depth ranges from 25 to 50 meter. Although most of the wind turbine tower structures in the world are monopole supported, many countries start to research on jacket structure. The purpose of present study is to design and analyses the most suitable support structure for 5MW offshore wind turbines in Taiwan.
Based on reviewed literature, different types of general jacket structures model are built. New types of jacket structures are successfully designed, known as modified tripod jacket structures. In this thesis, 14 types of jacket structures models have been constructed using SOLIDWORK design software. The finite element analysis (Beam Element Analysis and Shell Element Analysis) and buckle analysis are performed using ABAQUS/CAE package software.
In the experiment, MTS machine is used to perform the buckle test on small-scaled specimens. The experiments are conducted in two stages, first is to execute buckle test on the modified tripod solid structure. Second is to execute buckle test on steel hollow tube. The force-displacement data is measured and compared with the simulation results to evaluate the validity of the numerical method.
CAE result shows that, 0°modified tripod jacket structure has better behavior under stress loading. In buckle test, 90°modified tripod jacket structure is good performed. These four designs of modified tripod jacket structures simplify the process of construction and reduce the construction cost. This is because modified tripod jacket structures have less braces and less welding points.

並列關鍵字

Offshore Wind Turbine Tower ； Jacket Structure ； ABAQUS ； Finite Element Analysis ； Buckle Analysis

參考文獻

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