26-08-2013, 04:19 PM
Frequently Asked Questions on Wind Power Programme (FAQ)
Frequently Asked Questions.pdf (Size: 2.02 MB / Downloads: 216)
1. What is wind?
Wind is air in motion. Wind is mainly formed due to the Earth’s rotation and the
uneven heating of Earth’s surface by sunrays. The sunrays cover a much greater
area at the equator than at the poles. The hot air rises from the equator and
expands toward the poles that cause wind.
Air has a mass and mass in motion has a momentum.
Momentum is a form of energy that can be harvested.
Pwind = Power in the wind (W/m2)
ρ = Air density (kg/m3)
A = Projected area (m2) (wind turbine rotor area)
V = average wind speed (m/s)
the power increases with cube of wind speed
2. What is a wind turbine?
A wind turbine is a system which transforms the kinetic energy available in the wind
into mechanical or electrical energy that can be harnessed for any required
applications. Mechanical energy is most commonly used for pumping water. Wind
electric turbines generate electricity that can be utilized locally or transported to the
desired location through grid.
3. What are the different configurations of Wind Turbines?
There are two basic configurations of Wind Turbines. One is Vertical axis wind
turbine and the other is Horizontal axis wind turbine. The horizontal axis turbine has
seen technological and economical growth and it has become the commonly used
commercial turbines on large scale and the vertical axis turbines are still in the
demonstration purpose and small scale applications.
4. What does wind turbine contains or components of wind turbine?
Rotor:
The blades and the hub together are called the rotor. It is the rotating component
which converts kinetic energy available in the wind to mechanical energy. The rotor
hub connects the rotor blades to the rotor shaft. It is also the place where the power
of the turbine is controlled physically by pitching (A method of controlling the speed
of a wind turbine by varying the orientation, or pitch, of the blades, and thereby
altering its aerodynamics and efficiency) the blades. Hub is one of the critical
components of the rotor requiring high strength qualities.