What is the function of the fan blade?
Five can lookout "cut" more small, quiet is better. Because of the "cut" the wind is more uniform, with five fans not only brought the silencing effect from the comfort of view is also much more choice, fan blowing can achieve a wider range than block adjustment
Most of the fans are three blades. In addition, the three blades have better dynamic balance, not easy to oscillate, thus reducing the wear of the bearings, prolonging the service life and reducing the maintenance cost
The number of blades of a fan is often odd number, because it is easy to make the system resonance if the fan with even shape is used and the balance is not adjusted
Fewer leaves are likely to produce greater wind pressure, but the noise is greater, while the number of leaves is the opposite
