Optimal Design of Composite Wind Blades of A VAWT for Water Pumping

• Main Authors: Yao, Min-Heng, 姚旻亨
• Other Authors: Kam, Tai-Yan
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/43811806452290071239

碩士 === 國立交通大學 === 機械工程系所 === 103 === In this paper, an optimization technique is proposed to design the layer distributions of the composite blades of a vertical-axis wind turbine (VAWT). The VAWT is a hybrid wind turbine, which is composed of lift- and drag-type blades. The drag-type blades have same semi-circular cross-section. These two types of blades are sandwich structures. Composite materials have been used to manufacture the blades. The finite element code ANSYS is used to perform the stress analysis of the blades during the optimal design process. The accuracy of the finite element model has been verified using the experimental results obtained in a static test. The end forces of each blade extracted from the finite element analysis of the rotor structure are used in the local finite element model of the blade for designing the optimal layer distribution of the blade (termed as the Local Model). In the local optimal design process, the Genetic Algorism which can deal with discrete design variables is used to search for the optimal layer distribution of each blade. The optimal layer distributions of all the blades obtained at the local design stages of the blades are then used in the finite element analysis of the whole wind turbine rotor structure (termed as Global Model) to check whether the safety factors of the blades satisfy the safety factor constraints. If not, the end forces of each blade determined in the Global Model are again treated as the external forces of the blade in the Local Model to repeat the local optimal design process. The optimal design will be performed iteratively until the design variables (number of layers) converge. The proposed optimal design method can make the rotor structure of the VAWT reduce 26% of its initial weight.