How To Build Wind Turbine Blades
What makes the 3 thin blades on wind generators more efficient then say, a decorative country windmill?
If you look online for wind generators you’ll find a truck load of pictures of windmills that are mounted on thin poles that only have 3 thin blades. I’ve taken it up as a hobby to find how & to build myself one. But I’m retro. I don’t get why those 3 thin blades hooked up to a rotary engine sort of machine could be more efficient then then the nice homely country windmills that are composed of 6-10 blades inside a metal ring with of course the wind vein mounted on the back. I can understand this with those gigantic wind turbines on wind farms but i just want a smaller one based off one i could buy at a farmers market or something like that. I don’t want to stick it on a 30′ pole but instead plant it right on the roof of my home & run it like that.
Okay random wind physics genius who just happens to see my dilemma, tell me what I’m not putting together here please.
It’s actually not (just) efficiency that causes most wind turbines to only have 3 blades instead of 6 or 10 or such. Increasing the number of blades does increase the aerodynamic efficiency, but the increase gets smaller each time. For instance, increasing blade number from 1 to 2 ups efficiency by 6%, while 2 to 3 ups it by only 3%. The fact that more blades also mean smaller blades – so they can all fit – mean that eventually the efficiency benefit gets so small that the lack of stiffness and amount of materials becomes simply too much. Also, the fewer blades allow higher angular momentum (rotation speed) and decreased cost.
How to Build a Wind Turbine with PVC Windmill Blades.flv
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Windmax HY1000-5 1,000 Watt Max 24-Volt 5-Blade Residential Wind Generator Kit $1,099.00 Advantages of 5-blade wind turbines over 3-blade wind turbines 1) 5-blade wind turbines will greatly improve annual energy production in low wind conditions. For areas with average wind speeds of 11 MPH (5m/s). If you compare annual energy output to conventional 3-blade wind turbine, there is an increase of annual energy output of more than 60%. 2) 5-blade wind turbines will dramatically improve t… |
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Windmax HY400 500 Watt Max 12-Volt 5-Blade Residential Wind Generator Kit $649.00 Advantages of 5-blade wind turbines over 3-blade wind turbines 1) 5-blade wind turbines will greatly improve annual energy production in low wind conditions. For areas with average wind speeds of 11 MPH (5m/s). If you compare annual energy output to conventional 3-blade wind turbine, there is an increase of annual energy output of more than 60%. 2) 5-blade wind turbines will dramatically improve … |
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LEGO City Limited Edition Set #7747 Wind Turbine Transport $58.88 Transport and build a spinning wind turbine! LEGO® City is going wind-powered! Transport the wind turbines blades and motor on the trucks trailer, then extend it to carry the entire tower to the building site with the help of an escort vehicle to guide you through traffic. Put it all together and let the citys new wind turbine spin! # Contains extendable truck that fits the wind turbine parts! # … |