Pumps, fans and ventilation

Measured or manufacturer curves and declared fluid conditions.

flow, head or pressure rise, efficiency → hydraulic, shaft and electrical power

pump curve, static head, resistance curve → operating flow and head

baseline curve, speed or impeller change → scaled flow, head and power, similarity limits

surface pressure, vapor pressure, suction losses, elevation → available NPSH, comparison input

flow, pressure rise, efficiency → air power, shaft power

fan curve, duct resistance → airflow, static-pressure operating point

duct geometry, airflow, roughness, fittings → pressure loss, velocity

room volume, target air changes per hour → required volumetric airflow

clean and loaded curves, flow, replacement criterion → system pressure allowance, conditional replacement threshold