# Hydraulic Efficiency

on . Posted in Fluid Dynamics

Hydraulic efficiency, abbreviated as $$n_h$$, a dimensionless number, is the ratio of hydrodynamic energy in the form of fluid to the amount of mechanical energy delivered to the rotor.

## Hydraulic Efficiency Formula

$$\large{ n_h = \frac{ Q_a \; 100 }{ Q_t } }$$
Symbol English Metric
$$\large{ n_h }$$ = hydraulic efficiency   $$\large{dimensionless}$$
$$\large{ Q_a }$$ = actual flow rate output $$\large{\frac{ft^3}{sec}}$$ $$\large{\frac{m^3}{s}}$$
$$\large{ Q_t }$$ = theoretical flow rate $$\large{\frac{ft^3}{sec}}$$ $$\large{\frac{m^3}{s}}$$