Concept of Fan & Blower
How to Recognize Fan & Blower Types
There are two primary types of fans: Centrifugal fans, and Axial
fans.
Centrifugal fans use a rotating impeller to move air first radially
outwards by centrifugal action, and then tangentially away from the blade tips.
Incoming air moves parallel to the impeller hub and it turns radially outwards
towards the perimeter of the impeller and blade tips.
As the air moves from the impeller hub to the blade tips, it
gains kinetic energy. This kinetic energy is then converted to a static
pressure increase as the air slows before entering the tangential discharge
path.
Centrifugal fans are capable of generating relatively high
pressures. They are frequently used in ‘‘dirty’’ airstreams (high moisture and
particulate content), in material handling applications and in systems operated
at higher temperatures.
For more click on below link...
http://mechanical-engineerinterviewquestions.blogspot.in/2014/10/fan-blower-and-capacity-control-methods.html
