Pump Types and Selection Guide

Overview

Engineering reference data for Pump Types and Selection Guide in pumps.

Key Formulas

Pump Power

$P = \frac{Q \cdot H \cdot \rho \cdot g}{\eta}$

Hydraulic power / efficiency.

NPSH Available

$NPSH_a = \frac{P_s}{\rho g} + \frac{v_s^2}{2g} - \frac{P_v}{\rho g}$

Net Positive Suction Head available.

Affinity Laws

$Q \propto n, \quad H \propto n^2, \quad P \propto n^3$

Flow, head, power vs speed.

Variables

Symbol	Description	Unit
$P$	Power	W
$Q$	Flow rate	m³/s
$H$	Head	m
$\eta$	Efficiency	—
$n$	Rotational speed	RPM

References

• Original Source