What is Fan Power: Fan power defines the amount of energy required to operate the fan to produce a specific amount of Air flow. Fan power depends upon the air flow and static pressure.
How do we calculate the Power of a blower or fan:
Power = (Air Flow * Static Pressure) / (6356 * η)
where,
- Air flow in Ft³/min,
- Static Pressure in inH₂O (Inch of Water)
Affinity Law for Fan: Affinity law for fans and centrifugal pumps defines the changes in volume capacity, head (pressure) & power consumption because of the following:
- Change in Wheel Speed, RPM (Revolution per minute).
- Change in Impeller diameter.
Air Flow or Capacity(Ft³/min) varies as indicated in the equation: Q₂ = Q₁ * (N₂/N₁) * (D₂/D₁)³
Static pressure varies (inH₂O) as indicated in the equation: Sp₂ = Sp₁ * (N₂/N₁)² * (D₂/D₁)²
Power consumption (hp) varies as indicated in the equation: P₂ = P₁ * (N₂/N₁)³ * (D₂/D₁)⁵