Hydraulic Diameter

[Sefrick]

I know that for duct flow Dh=4hb/2(h+b) and that for a pipe the hydraulic diameter is just the ID of the pipe.

What diameter would you use for a hollow pipe? i.e like the outer pipe on a pipe in pipe heat exchanger.

Thanks for any input.

 

[katmar]

Do a search here on "annular flow". This has been discussed many times before.

Katmar Software
Engineering & Risk Analysis Software

http://katmarsoftware.com

 

[zdas04]

I even wrote an FAQ on the subject faq378-1142


David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

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