gas pipeline hydraullics

[UmohEffiom]

Dear Friends

Kindly help with the most appropriate equation for calculating the friction factor in a a gas pipeline under turbulent condition

Thanks

[fucheng]

Colebrook-White equation will work for you case (Nre>4000)

[UmohEffiom]

Mr Fucheng
if i am correct this is the equation you are talking about:F^(-1/2)=-2LN((e/3.7D)+2.51/(Re(F^1/2))
Please Kindly explain how to go about it since we have two F''

[link Point to another website Only the registered members can access]
thanks

[gunnarhole]

If you go to Wikipedia "Darcy Friction Factor Formulae" you will find an description of the Goudar-Sonnad equation which was published in Hydrocarbon Processing in August 2008. This has an explicit solution so an iterative approach is not necessary. Goudar and Sonnad published an earlier paper in the April 2007 issue which covered similar material. Both worth reading if you can find them. The answer you want is at Wikipedia.

Regards

[Grimm]

According to the definition Reynolds number can be calculated using equation:
Re=ωdρ/μ=ωd/ν;
Laminar flow - Re<2300;
Transition zone (or crossover) - 2300<Re<10000;
Turbulent flow - Re>10000.
For a laminar flow (Re<2300) the equation for calculation of Friction Factor ( λ ) is as follows:
λ=64/Re;
For a laminar flow there’s no dependence of λ from roughness of pipe walls.
For a turbulent flow (Re>2300) the equation for calculation of λ is as follows:
λ=0,316/Re^0.25 - this equation can be applied for hydraulically smooth pipes and for the Reynolds number not exceeds Re>100000;
For rough pipes λ can be calculated according the equation:
1/(√λ)=-2lg⌊ε/3.7+(16.81/Re)^0.9 ⌋
in this equation is:
ε - relative roughness, that can be calculated based on the equation:
ε=e/d_e
where is:
e (in mm) - intermediate size of pipe’s hills or hillocks (pipe roughness) can be found in the appropriate theoretical tables;
d_e (in mm) - equivalent diameter of a pipe.
I hope this info will be helpfull

[UmohEffiom]

Thanks Grimm.. Please can you kindly give me a reference

[Grimm]

This info was taken from the Russian book "Pavlov K.F., Romankov P.G., Noskov A.A. "Examples and tasks for the course of processes and apparatuses of chemical technology", pages 21-22, equations 1.38, 1.40, 1.41, 1.42.

[UmohEffiom]

Thanks Mr Grimm.. Please can you upload the book... or send a link where i can download it from.