الفهرس | Only 14 pages are availabe for public view |
Abstract The main objective of this thesis is to study the dynamic behavior of an optimized composite wind turbine blade of a previous research. This thesis employs methodologies using classical theory, as well as probabilistic and numerical techniques for the study of the wind turbine blade. Blade Element Momentum theory (BEM) is used for the aerodynamic simulation, Sandia method (also known as Veers method) is used to generate a turbulent wind field. Euler Beam theory is used for the rotor blade structure analysis, and a rainflow cycle counting technique and Miner{u2019}s sum are used to estimate the fatigue life of the blade. Modal analysis of the turbine blades showed that the natural frequency of the turbine blade first mode is 3.37 Hz. The dominant frequency in the wind is 0.83 Hz, which means the blade is safe from resonance. Fatigue analysis for the blade results showed that the service lifetime of the blade until failure is about 17 years for the turbine operating speed of 36 rpm, and about 15.8 years for the operating speed of 47 rpm, which are less than the expected service life of 20 years by 14.7% and 20.9% respectively |