New answers tagged energy
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Efficiency = heat moved versus energy consumed. For a heat pump this is either SEER or Coefficient of Performance. Heat moved compared to energy used should be around 2 to 5 in equivalent units (COP). SEER includes USA-standard units so it is a larger number, but more or less means the same thing.
So you need to measure the heat removed/added - mass ...
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to get more power out of the available wind, it is better practice to increase the diameter of the blade disc instead of adding more blades, which greatly increases the size & complexity of the main hub to which the blades are affixed.
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Aside from the efficiency, the blades of wind turbines are basically a wing, aerofoil, the actual upwash and downwash zone are much greater than the wing's cross-section.
If the blades are too close they can interfere with each other flow stream and actually create debilitating turbulence.
The wind turbines are designed to work in a wide range of winds.
The ...
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The function of the wind turbine is to extract as much as possible energy from the moving mass of air. The energy of a mass $m$ of air is
$$KE = \frac{1}{2}m v^2$$
and the power is (because the mass rate is $\dot{m} = \rho A v)$
$$P = \frac{1}{2}\dot{m} v^2=\frac{1}{2} \rho A v^3$$
So, the energy in the air is a function of the velocity. As energy is ...
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