Wind Flow and Various Propellers

Press the button and point the stream of air to the different propellers. The display will show their efficiency. We might be led to think that a wind turbine would be more efficient if the rotor had more blades. In reality three blades increase the efficiency by a mere 3 % compared to a propeller with two blades. By adding more blades the relative increase in efficiency will decrease even further. Turbines with more blades are often used for pumping water. It is easy to start rotating this type of turbine even at low wind speeds but at higher speeds its efficiency drops.