Fan Power
Fan Power
A fan’s power follows from the air flow it moves against the pressure rise it produces, divided by its efficiency.
The power is P = ΔP·Q/η. where ΔP is the pressure rise, Q the volume flow and η the fan efficiency.
Inputs
dP := 500 Pa=500 Pa
Q := 2 m^3/s=2 m^3/s
eta := 0.7=0.7
Divide the air power by the efficiency.
P := dP·Q/eta=1428.57 W
Results
The pressure×flow product is the useful air power; dividing by efficiency gives the shaft (motor) power. Lower duct resistance cuts the pressure rise and the energy bill.
Assumptions & limitations
- Incompressible air.
- Constant efficiency.
- Steady operation.