Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Suction Absolute Pascals (Pa)

Required number input.

Vapor Pressure Pascals (Pa)

Required number input.

Density Kg Per M3 (kg/m³)

Required number input.

Gravity Meters Per Second Squared (m/s²)

Required number input.

Suction Speed Meters Per Second (m/s)

Required number input.

Available pump NPSH from absolute suction pressure head plus velocity head minus vapor pressure head; supply losses are already reflected in suction pressure. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Npsh Meters (m)

The resulting npsh meters returned as a number.

• Fan, pump, turbine, and propeller performance varies with speed, flow, head, density, efficiency map, cavitation margin, installation, control, and off-design operation. Similarity or ideal-power equations do not replace manufacturer curves.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Bernoulli Total Head

  Total ideal-flow head as elevation plus pressure head and velocity head; excludes friction and pump terms.

• Pump Head Total Dynamic

  Total dynamic pump head from signed static lift plus positive friction, discharge-pressure and velocity heads.

• Cavitation Number

  Cavitation number (p−pv)/(½ρv²) using local absolute pressure and vapor pressure.