Th3 equation i liked is w=370×(deltaP ×density ×d^5)^0.5
W=flow in lb÷h
DeltaP=friction loss in lb÷in^2(psi) per 100 ft
Density
D=inside diameter of pipe in inches
This is a form of Fanning or Darcy formula with friction factor=0.0055
This friction factor corresponds to approximately the following
Commercial steel pipes
No. Reynolds=10^5
Williams and Hazen C factor=110
For other friction factors multiply the right sid3 for
(0.0055÷friction factor)^0.5
The friction factor can b3 approximaTed by
Laminar flow f=16÷Re
Commercial pipes f=0.054÷Re^0.2
Smooth tubes f=0.046÷Re^.2
Extremely rough pipes f=0.013
Where Re is the well known. In this case
Friction factor=hl÷(4×(L÷D)×(u^2÷(2g)))
hl÷friction head in feet
L length in Feet
D diameter in feet