Centrifugal Fan Inlet Design
Centrifugal fans often contain a ducted housing to direct outgoing air in a specific direction or across a heat sink.
Centrifugal fan inlet design. Because of their simple design radial fans are well suited for high. Position of inlet box and air entry to inlet box in determined from drive side of fan. Energy balance is established at fan inlet intermediate stage of impeller and outlet stage of volute scroll casing. Volume flow up to 250 000 m h single inlet design up to 500 000 m h double inlet design pressure rise up to 15 000 pa single stage up to 30 000 pa double stage shaft support with overhung arrangement or on both sides.
Fan parts impeller design the centrifugal fans impeller have five basic blade shapes and a number of impeller configurations i e dwdi double width double inlet or swsi single width single inlet. Single inlet single width sisw or double inlet double width didw shaft power up to 200 kw. Radial fans are industrial workhorses because of their high static pressures upto 1400 mm wc and ability to handle heavily contaminated airstreams.
During this process stage velocity pressure and discharge at different stages are calculated. Inlet box positionsfor centrifugal fans amca standard 99 2405 83 notes. The impeller design will depend on the aerodynamic duty and the operating conditions. When the impeller rotates air is allowed to enter the fan around the open space between the impeller and the shaft and is forced to proceed at a right angle to the.
Reference line is the top vertical axis through center of fan shaft. Radial forward curved and backward curved see figure 5 3. The effects of the blade inlet. ρᵢ is the density of the air at the inlet edge of the fan blades.
However in many cases space constraints or other factors prohibit designers to allow for ideal conditions. Fan installations with system effects should be avoided if possible. Fan types typically affected by both inlet and outlet conditions are inline fans both axial and centrifugal and housed single inlet centrifugal fans. A centrifugal fan is a mechanical device for moving air or other gases in a direction at an angle to the incoming fluid.
Such a fan is also called a blower fan biscuit blower citation needed or squirrel cage fan because it looks like a hamster wheel. W is the width of the blades in a centrifugal fan parallel to the axis of rotation of the impeller. Types the major types of centrifugal fan are. In centrifugal fans the air flows at right angles to the inlet air direction and throws the air outward toward the outlet through the action of deflection and centrifugal force.
Pᵢ is the pressure of the air at the inlet edge of the fan blades. Rₐ is the specific or mass gas.