# Blog Archives

## Closed Conduit Hydraulics – Hazen Williams Equation

Hazen-Williams can be used to determine the flow characteristics in closed conduits (pipe systems).

### For Velocity

$$ V = 1.318CR^{0.63}S^{0.54} \text{ (US)}$$

$$ V = 0.849CR^{0.63}S^{0.54} \text{ (SI)}$$

S = slope, in decimal form. This is equivalent to \( h_f/L\)

R = hydraulic radius, \(\text{(Area of flow)}/\text{(wetted perimeter)}\)

C = Roughness Coefficient, get this from a table (available in both the AIO and CERM) Click here to continue reading