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Old 11-03-2015, 05:44 PM   #25 (permalink)
aerohead
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Quote:
Originally Posted by jamesqf View Post
Not so - see the link I posted. Under the right conditions, you can extract more energy from the wind that it takes to propel the vehicle. Of course that's actual wind, not relative, so it doesn't work in calm conditions. Otherwise, how's it logically different than powering a car hooked to a stationary wind turbine?
The article I looked at was about a turbine-propulsed vehicle running downwind,which would not be germane to a discussion about a turbine generator on the front of an I.C.-powered car.
*Turbines cannot have over-unity efficiencies when extracting work from a working fluid.
*Generators cannot have over-unity efficiencies when converting shaft work to electrical power.
*The theoretical maximum mechanical efficiency for a turbine is in the 80% range.
*The turbine nacelle will add drag
*The support structure which holds the turbine unit in the airstream will add drag.
*The amount of energy harvested from the turbine will always be less than the energy entering the system,or you're violating the 2nd-Law of Thermodynamics and into unicorn territory.
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