the shape of wake behind a wind turbine is normally assumed to have a hat shape for the models used in wind farm layout optimization purposes; however, it is know from experimental tests and numerical simulations that this is not a real assumption. in reality, the results of actual measurements and detailed numerical simulation show that the velocity in wake region has a s-shape profile. the pr...

accurate modeling of the wind energy conversion system is necessary to design and implementation of the control loop for the generator and the frequency converter, in order to extract maximum power from the wind and to investigate the effects of interconnection between wind farms and power system. in this paper the combination of a permanent magnet synchronous generator loaded with a diode rect...

[1] It took the solar polar passage of Ulysses in the early 1990s to establish the global structure of the solar wind speed during solar minimum. However, it remains unclear if the solar wind is composed of two distinct populations of solar wind from different sources (e.g., closed loops which open up to produce the slow solar wind) or if the fast and slow solar wind rely on the superradial exp...

Derivation of sea surface wind direction is a key step of sea surface wind retrieval from spaceborne Synthetic Aperture Radar (SAR) data. This technical note describes an implementation of the Local Gradient (LG) method to derive sea surface wind directions at a scale of a few kilometers from X-band spaceborne SAR TerraSAR-X (TS-X) data in wide swath mode. The 180 ̋ ambiguity in the derived sea ...

Nowadays, power systems, energy generation by wind has been very important. Noting that the production of electrical energy by wind turbines on site is depend on to several factors (such as wind speed and profile site for the turbines, especially off the wind input speed, wind rated speed and wind output speed disconnect) is dependent. On the other hand, there are several different types of tur...

Many stars are known to drive stellar winds of the solar wind type. Thus when moving through the ambient interstellar medium these stars not simply ionize this medium but also interact as moving stellar wind systems. Only neutral interstellar gas components can directly enter the inner stellar wind region and there undergo charge exchange reactions with the supersonic stellar wind protons. Ther...

Nowadays, power systems, energy generation by wind has been very important. Noting that the production of electrical energy by wind turbines on site to several factors (such as wind speed and profile site for the turbines, especially off the wind input speed, wind rated speed and wind output speed disconnect) is dependent. On the other hand, several different types of turbines in the market the...

Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind ...

in a steam power plant, the temperature of the cooling water leaving the condenser for recyclingshould decrease. this is achieved in a cooling tower. the heller cooling tower does not require waterfor operation, thus, it is a suitable system for use in thermal power plants throughout iran. wind is anenvironmental factor that unfavorably affects the performance of a cooling tower. previous studi...

With the expansion of wind farm installations in most countries all over the world, the power generation has already significantly influenced on the stability and security of the power grid after gridconnection. Wind power forecasting is an effective method for guarantees stability of the power output from wind farm. This paper proposed an improved GM(1,1) based prediction method, and focuses o...