Colebrook White v.s. Manning Equation for Pipe Flow

[xkybb]

Hello!

I know that both Colebrook White Equation and Manning Equation are commonly used for the design of gravity pipe flow.

However, it is more common in my country for people to use:
1. Colebrook White Eqaution for gravity pipe flow
2. Manning Equation for open channel flow

Does anyone know the reason behind? Is it just a matter of common practice?

 

[xkybb]

Does anyone know please? : [

 

[cvg]

its not common practice

 

[jgailla]

I've never used Colebrook-White for gravity pipe or open channel, only Manning.

 

[xkybb]

So no one would use Colebrook White Equation for gravity pipe design?

 

[cvg]

it is used, but it seems more often used for pipelines than for drainage.

http://www.eng-tips.com/search.cfm?q=Colebrook+White+&action=search

 

[fel3]

I use Mannings for water flowing outdoors in open channels, water/sewage flowing in non-pressure pipelines (gravity flow in pipes is just another type of open channel flow), and water flowing under pressure in large diameter irrigation and storm drainage piping. I use Hazen-Williams for water flowing under pressure in transmission mains and distribution systems. I use Colebrook-White mostly for natural gas and I used to use it sometimes for pumping station piping. However, all three of the formulas I cite can be adapted for any of the water flow situations I mentioned.

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