نتایج جستجو برای: wind turbines

تعداد نتایج: 86431  

2002
J. Green E. Muljadi

Most small wind turbines use permanent magnet (PM) generators. The generators are usually direct-drive (i.e., no gearbox is required). Direct-drive PM generators are characterized by low maintenance and high efficiency. Small wind turbines are usually self-starting and require very simple controls. Cogging torque is an inherent characteristic of PM generators and is caused by the geometry of th...

2015
Zijun Zhang ZIJUN ZHANG Yong Chen

Improving performance of wind turbines through effective control strategies to reduce the power generation cost is highly desired by the wind industry. The majority of the literature on performance of wind turbines has focused on models derived from principles versed in physics. Physics-based models are usually complex and not accurate due to the fact that wind turbines involve mechanical, elec...

2014
YUAN Wei TIAN Wei HU Hui

An experimental study was conducted to investigate the effects of relative rotation direction on the wake interferences among two tandemwind turbines models. While the oncoming flow conditions were kept in constant during the experiments, turbine power outputs, wind loads acting on the turbines, and wake characteristics behind the turbines were compared quantitatively with turbine models in eit...

In this paper, configuration of ‘Vestas_V47’ wind turbines in a wind farm is investigated using computational fluid dynamics (CFD). First the geometry of wind turbine has been modeled, then unstructured mesh around the blades, nacelle and tower have been generated and finally the SST k-ω model has been used for modeling the turbulence. Afterward wind’s velocity contour f...

Journal: :international journal of occupational hygiene 0
milad derakhshan jazari msc of occupational health engineering, tehran university of medical sciences, tehran, iran mahdyeh boubehrejh national center of air and climate change, department of the environment, tehran, iran maryam avishan national center of air and climate change, department of the environment, tehran, iran jamshid gholampour [email protected] mohammad reza monazzam esmail pour professor of occupational health engineering, tehran university of medical sciences, tehran, iran mohsen meshkani [email protected]

original article   introduction: wind-turbine noise emission and its environmental impact are considerable issues nowadays. considering the importance of the issue, the purpose of this study was to prepare noise map and wind turbines sound characteristics on the largest wind farm of iran. method: this study was carried out in two phases:1) in order to prepare the daytime sound level (ld) noise ...

2014
Olatz Grande Josune Cañizo Itziar Angulo David Jenn Laith R Danoon David Guerra David de la Vega

The potential impact that offshore wind farms may cause on nearby marine radars should be considered before the wind farm is installed. Strong radar echoes from the turbines may degrade radars' detection capability in the area around the wind farm. Although conventional computational methods provide accurate results of scattering by wind turbines, they are not directly implementable in software...

In recent years, the use of offshore wind turbines has been considered on the agenda of the countries which have a significant maritime boundary due to more speed and stability of wind at sea. The aim of this study is to investigate the effect of wind turbulence on the aero-hydrodynamic behavior of offshore wind turbines with a monopile platform. Since in the sea, the wind turbine structures ar...

2015
V. Churkin M. Lopatin

sales in the US. The forecasting method is based on the application of the Bass model and the generalized Bass model of innovations diffusion under replacement purchases. In the work an exponential distribution is used for modeling of replacement purchases. Only one parameter of such distribution is determined by average lifetime of small wind turbines. The identification of the model parameter...

2016
Hyungyu Kim Kwansoo Kim Insu Paek Carlo L. Bottasso Filippo Campagnolo

In this study, the effect of active induction control of upstream wind turbines is investigated. Two scaled wind turbines having a rotor diameter of 1 m with a spacing of four times of the rotor diameter were used to experimentally validate the concept. Also, an in-house c code was used to simulate the same two wind turbines and see if the experimental observations can be obtained. From the exp...

2017
Karam Y. Maalawi

With the growing demand for cost-effective wind energy, optimization of wind turbine components has been gaining increasing attention for its acknowledged contributions made to design enhancement, especially in early stages of product development. One of the major design goals is the accurate determination of structural dynamics and control, which is di‐ rectly related to fatigue life and cost ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید