Theory 62/Engineering & infrastructure/Pump efficiency
Efficiency Peaks at the Design Point
The claim
Pump efficiency is set by the ratio of operating flow to best-efficiency flow, so throttling a pump costs more than running a smaller one.
01Mechanism
Impeller geometry optimises at one flow; the ratio measures the departure.
02Prediction
Efficiency should fall as the ratio departs from one.
03Refutation
Efficiency tracking head alone would remove flow matching.