Pipeline Toolbox
Function Reference Manual
Early Public Release DD-00011-000

3.5.1 hazen_williams_p - Hazen-Williams pressure drop P
r = hazen_williams_p(q,d,c,sg=1)

Calculate the Hazen-Williams pressure drop across a pipeline. Common values for the roughness factor of the pipe C by material are provided in table 3.5.1.

Material Range for C
Asbestos-Cement 140
Cast iron new 130
Cast iron after 10 years [107,113]
Cast iron after 20 years [89,100]
Cement-Mortar Lined Ductile Iron Pipe 140
Concrete [100,140]
Copper [130,140]
Steel [90,110]
Galvanized Iron 120
Polyethylene 150
Polyvinyl chloride 150
Fibre-reinforced plastic 150
Tin 130
Lead [130,140]

Arguments

q

Volumetric flow rate Q (m3/h).

d

Pipe internal diameter D (m).

c

Roughness factor of the pipe C, see table above.

sg

Liquid specific gravity Sg.

Returns Pressure drop due to friction P (kPa /km ).

Possible Errors

Hazen-Williams factor must be >0

A negative or zero Hazen-Williams factor was supplied.