Hazen Williams Equation
The Hazen–Williams Equation is an empirical equation widely used in practice. It is especially applicable for smooth pipes of medium and large diameters and pipes that are not attacked by corrosion .
For calculating the velocity of flow in pressurized system, hazen william formula is frequetly used and is as below;
For circular conduits, the formula transforms to,
and, the discharge is given by,
Q = Discharge in cubic meter per hour,
d = diameter of pipe in mm,
V = velocity in mps,
r = hydraulic radius in m,
S = slope of hydraulic gradeline,
C = Hazen-Williams coefficient.
Hazen williams coefficient for different pipe materials are as below;
Recommended Values for
|Concrete (RCC & PSC) with socket and spigot joints||150||120|
|Steel, welded joints||140||100|
|Steel, welded joints lined with cement and bituminous enamel||150||120|