Horizontal axis wind turbines suffer from aerodynamic inefficiencies in the blade root region (near the hub) due to several non-aerodynamic constraints. Aerodynamic interactions between turbines in a wind farm also lead to significant loss of wind farm efficiency. A new dual-rotor wind turbine (DRWT) concept is proposed that aims at mitigating these two losses. A DRWT is designed that uses an e...

Operating horizontal axis wind turbines create large-scale turbulent wake structures that affect the power output of downwind turbines considerably. The computational prediction of this phenomenon is challenging as efficient low dissipation schemes are necessary that represent the vorticity production by the moving structures accurately and that are able to transport wakes without significant a...

Many challenges exist for the operation of wind turbines in an efficient manner that is reliable and avoids component fatigue and failure. Turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, possibly causing component fatigue and failure. Wind turbine manufacturers are highly motivated to reduce component fatigue and ...

The majority of studies on the effects of wind energy development on wildlife have been focused on birds and bats, whereas knowledge of the response of terrestrial, non-flying vertebrates is very scarce. In this paper, the impact of three functioning wind farms on terrestrial small mammal communities (rodents and shrews) and the population parameters of the most abundant species were studied. T...

One part of the solution to the problem of climate change is the use of wind energy for electricity generation. Onshore wind farms usually consist of a number of horizontal axis wind turbines closely spaced in clusters and they are often sited on complex terrain. Various models have been developed in the past to estimate the wake effects and optimize the siting of a wind farm, but they were mai...

Operating horizontal axis wind turbines (HAWT) generate large-scale wake structures that can have considerable impact on downwind turbines. A HAWT exposed to vortices from upwind turbines generally produces reduced power and experiences increased structural vibrations that cause disproportionally accelerated material fatigue. Numerical simulation of the turbulent flow field is a viable approach...

A wind-tunnel investigation was carried out to characterize the spatial distribution of the integral time scale (Tu) within, and in the vicinity of, two model wind farms. The turbine arrays were placed over a rough wall and operated under high turbulence. The two layouts consisted of aligned units distinguished only by the streamwise spacing (∆xT ) between the devices, set at five and ten rotor...

The performance of wind turbines can be negatively affected by the presence of uncertainties. We introduce a comprehensive multi-physics computational model EOLO that enables the estimation of aerodynamic and structural characteristics assiociated with horizontal axis wind turbines, and use it to study the impact of uncertainties on the aerodynamic performance and noise. We consider variability...

Electrical energy control systems for energy storage devices are required for power quality and balance within wind systems. In the context of rapidly expanding of distributed energy sources, the wind energy turbines are in the center of interest. This paper presents a control system for small power wind turbines of 3kW. As practical results are depicted modeling and simulation waveforms for th...

A detailed review of the current state-of-art for wind turbine blade design is presented, including theoretical maximum efficiency, propulsion, practical efficiency, HAWT blade design, and blade loads. The review provides a complete picture of wind turbine blade design and shows the dominance of modern turbines almost exclusive use of horizontal axis rotors. The aerodynamic design principles fo...