# Discharge Velocity

Written by Jerry Ratzlaff on . Posted in Geotechnical Engineering

Discharge velocity, abbreviated as q, is the rate of water through a porous medium per unit of total area perpendicular to the direction of flow.

## Discharge Velocity formulas

 $$\large{ q = V_t \; A_c }$$ $$\large{ q = k \; i \; A_c }$$

### Where:

 Units English Metric $$\large{ q }$$ = discharge velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$ $$\large{ A_c }$$ = area cross-section $$\large{ft^2}$$ $$\large{m^2}$$ $$\large{ i }$$ = hydraulic gradient $$\large{dimensionless}$$ $$\large{ k }$$ = permeability coefficient $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$ $$\large{ V_t }$$ = total volume of soil $$\large{ft^3}$$ $$\large{m^3}$$