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Questions tagged [wind-power]

For questions related to power (mechanical or electrical) generated from wind.

56 questions
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How to correctly size the blades for a small educational wind turbine?

I want to design a small wind turbine that can be easily carried out of the classroom into the sports field in relatively low-wind conditions (5-15km/h) that can power a small ultra-bright 5V LED - just enough to show that it works. How do I…
jhabbott
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How to calculate Power of motor when used as a generator?

How can you calculate how much power can be generated by a motor when used as a generator (like a motor used in a wind turbine)? Does the power depend on how fast the magnet is rotated? If so, is there a equation that lets you know given the rpm,…
user510
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Why don't we just build a giant wind turbine?

The power generated by a wind turbine is given by: $$\mathrm{Power} = \frac{1}{2}C\rho AV^3$$ Where: $\rho = \text{Air density}$ $C = \text{Coefficient of performance}$ $A = \text{Frontal area}$ $V = \text{Velocity of the wind}$ In other words,…
Chong Lip Phang
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To what degree are wind and water turbines exchangeable?

Assuming maximum efficiency is not the primary concern (but net positive efficiency is), to what extent could a wind turbine operate in water and vice versa? How do the different turbine types fare in this respect? I.e., HAWT / VAWT (Savonius,…
Zubo
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5
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Relationship between wind velocity, turbine rotor diameter, and power output

I'm trying to understand and identify the equations to use in defining the relationship between wind velocity, turbine rotor diameter, and power output for a wind turbine. To simplify my question, let's use the following assumptions: Average wind…
Dwiparna Datta
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Identifying category of wind turbine

I recently saw a wind turbine that I'm trying to identify the type or category of. Basically, the turbine looks like two squirrel cage fans mounted side by side on a fairly tall ~40' pole. The blades of the turbines rotate along the horizontal…
user16
5
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3 answers

Why not design a Wind Turbine like an Anemometer?

Anemometer measures wind speed. It's shaped with little cups---hollow half-spheres. That looks very logical as the cups grab the wind and the other side is rather streamligned to cut through the air as it spins. So why are there no wind turbines…
DrZ214
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5
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Advantages/Disadvantages of two-bladed windmill?

The vast majority of wind turbines I have ever seen feature 3 blades, as shown here: Recently while driving through western new York state, however, I passed by several turbines featuring only two blades, as shown here: What advantages and…
Timpanus
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4
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Why does my model of a wind turbine show high RPM with low power output?

I am designing a wind turbine to generate 1300 W. I modeled the output voltage of an AC generator using the following specifics: Number coil turns = 300. Copper wire gauge = 1.02 mm. Knowing the density of copper, I calculated the weight of the…
user510
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Efficient 3D mesh topology for CFD simulation of turbine blade

I´m developing a tool to generate an openFoam wind tunnel case of a wind turbine. I already have the blade geometry constructed, but I'm really new to CFD and parametric meshing. I found some articles where they mention a C topology to mesh the…
efirvida
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Do 3 blade wind turbines generate more power than a 9 blade, all else being equal?

After doing some research, I have come to the realization that 3 blade design horizontal turbines have the greatest maximum coefficient of performance. Most sources seem to agree a Cp of ~0.45 at TSR=7 is optimal for 3 blade designs. The power…
David_M16
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What is the power and max flow rate required to rotate a 300 W wind turbine?

I have purchased a wind turbine with a power of 300 W, the start up wind speed is 2.5 m/s, rated wind speed is 11 m/s, and the survival wind speed is 45 m/s, and what I'm going to do is to make an educational modeling for how to generate electrical…
Mohamed AbdelAlim
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Why not build a wind turbine like a vertical Kaplan turbine?

Vertical Kaplan turbines are often used for hydropower plants. They can have an efficiency of more than 90%. Why don't we see similar designs for wind power? I mean one could imagine to redirect wind from horizontal to vertical direction and then…
asmaier
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Why wind turbine dont use high lift coefficient airfoils?

All wind turibne use low lift coefficent airfoils from 1.0 to 1.5. Why not use high CL airfoils to get maximum torque? http://airfoiltools.com/airfoil/details?airfoil=s812-nr
user207141
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Is the main goal for wind turbines to take maximum energy for a given diameter?

If you increase the number of blades, that will increase torque, for the same RPM you get more power,...simple logic So why only three blades, is main goal for wind turbine take maximum energy for given diameter?
user207141
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