How many blades is best?
These days ceiling fans are available with any number of blades from one to eight, although any number below 3 and above 6 is for novelty or decorative purposes only. Most fans have 4 or 5 blades, some are adaptable to take either. Most people assume that more blades move more air, i.e. a fan with five blades moves more air than a fan with four blades. This, in fact, is incorrect. More blades results in a greater load on the motor, and a greater load on the motor causes it to operate at a slower speed. A fan with less blades operating at a faster speed will more more air than a fan with more blades operating at a slower speed. This is why most commercial fans have three blades and a high speed motor, to provide the greatest amount of airflow efficiently. However, one thing about commercial fans is, noise is less of a factor than in residential situations. A 3 blade fan operating at a high speed is often quite noisy– not a buzz or hum, but the helicopter noise of air moving. The greate
