Hazen-Williams Equation Flow through a Pressurized Pipe

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

The Hazen-Williams Equation can be used for flow through an open channel or through a pressurized pipe.

Hazen-Williams Equation flow through a pressurized pipe formula

(Eq. 1)  \(\large{ p_d = \frac{4.52 \; Q^{1.852}} {C^{1.852} \; d^{4.8704}}  }\)     (US units)

(Eq. 2)  \(\large{ p_d = \frac{10.67 \; Q^{1.852}} {C^{1.852} \; d^{4.8704}}  }\)     (SI units)


\(\large{ p_d }\) = pressure drop over the length of pipe

\(\large{ Q }\) = flow rate

\(\large{ C }\) = Hazen-Williams Coefficient

\(\large{ d }\) = pipe inside diameter (ID)


Tags: Equations for Pipe Sizing Equations for Hazen-Williams