none

• Main Authors: Chun-Chieh Hung, 洪浚傑
• Other Authors: Jiun-Ren Hwang
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/477qt5

碩士 === 國立中央大學 === 機械工程學系 === 107 === This study consists of two parts. In part one, we investigated the wind-induced loads on the NREL Phase VI wind turbine. We noticed that if the inputs of simulations were the 2D airfoil aerodynamics coefficients only, the results will be apparently different from the experimental results due to rotating effect of blades. So, we used two different 3D stall delay correction models, which were derived by Snel and Lindenburg, to account for the rotating effect of blades. After modification of aerodynamics coefficients, the results showed well agreement between experiment and simulation. Furthermore, we discussed the wind-induced loads under different pitch angles or rotor speeds. The results showed that raising pitch angle or rotor speed increased the Low Speed Shaft Torque due to A.O.A was far from stall range. In part two, the stresses of NREL 5MW OWT tower were investigated. We studied six design load cases (DLCs) which should be processed ultimate load analysis according to the IEC 61400-3 standard. The ocean parameters of Taiwan west coast were adopted as the inputs of DLCs. The output loads of GH-Bladed software were transformed and imported to ANSYS Workbench. The results showed that the safety factors of tower under DLC 1.6b and 6.3b was lower than those recommended in IEC 61400-3. It indicated that the original design of NREL 5MW OWT may not afford the extreme wind and ocean conditions at Taiwan west coast. Therefore, we modified the thickness of tower to make the safety factor of tower higher than the suggestion.