a comprehensive review of fatigue behavior and fatigue design of heavy section wind turbine castings made of ductile iron en-gjs-400-18-lt is performed. common metallurgical defects that are affecting fatigue behavior of this material were studied. review of different researches on quantitative effect of chunky graphite and micro structure on fatigue behavior of en-gjs-400-18-lt was performed. ...

Natural wind is stochastic, being characterized by its speed and direction which change randomly and frequently. Because of the certain lag in control systems and the yaw body itself, wind turbines cannot be accurately aligned toward the wind direction when the wind speed and wind direction change frequently. Thus, wind turbines often suffer from a series of engineering issues during operation,...

Boundary-layer wind tunnel provides a unique platform to reproduce urban, suburban and rural atmospheric boundary layer (ABL) by using roughness devices such as vortex generators, floor roughness, barrier walls, and slots in the extended test-section floor in the contraction cone. Each passive device impacts wind properties in a certain way. In this study, influence of various passive devices o...

in order to restrain the potential of wind energy, the first step is to determine the wind energy potential. in this study the wind data was used from the three-hour frequency recording of 10-year period (2002-2011). to predict the occurrence probability of each wind speed, the two-parameter weibull function was used. the goodness of fit test by chi-square test showed that the wind speed distri...

In above rated conditions, wind turbines are often subjected to undesirable high structural loading. We investigate two feedback control techniques in combination with a feedforward control method for reducing blade flap bending loads in above rated wind conditions. The feedback controls studied include both disturbance accommodating/tracking and integral augmented/repetitive types that incorpo...

Wind generation is hectic by nature, making wind power forecasting highly challenging, particularly for short time frames. Forecasting of wind power is becoming progressively more important to power system operators and electricity market.Wind power is variable and irregular over various timescales as it is weather dependent. Thus precise forecasting of wind power is acknowledged as a major con...

The assessment and validation of the quality of satellite scatterometer vector winds is challenging under increased subcell wind variability conditions, since reference wind sources such as buoy winds or model output represent very different spatial scales from those resolved by scatterometers (i.e., increased representativeness error). In this paper, moored buoy wind time series are used to as...

The blades of a wind turbine have the most important job of any wind turbine component; they must capture the wind and convert it into useable mechanical energy. The objective of this work is to determine the mechanical power of single big C-section of vertical wind turbine for wind car in a two-dimensional model. The wind car has a vertical axis with 3 single big C-section blades mounted at an...