Engineering Fundamentals of Boiler Feed Pump Sizing
A boiler feed pump is a critical component in steam thermal power generating stations and industrial boiler plants. It receives treated feedwater from the deaerator storage tank and boosts pressure above operating boiler pressure to inject fluid safely into the boiler drum.
Total Dynamic Head (TDH) Formula
The total dynamic head must overcome the static elevation difference, boiler operating pressure, and cumulative friction losses through the feedwater piping system:
TDH = Static Head + Friction Head Loss + Pressure Head + Velocity Head
Net Positive Suction Head Available (NPSHa)
To prevent damaging cavitation in high-temperature feed water pumps, NPSHa must strictly exceed NPSH required by the pump manufacturer:
NPSHa = (P_atm / (ρ × g)) + H_suction - H_friction - (P_vapor / (ρ × g))