pressure drop with few knowns

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Joined: Thu Mar 04, 2010 9:50 pm

pressure drop with few knowns

Post by flowman » Thu Mar 04, 2010 9:54 pm

My customer asked for the pressure drop in the exhaust pipe of his generator. I've found the correct formula, but I don't know some of the required values for constants. Where can I find pipe roughness, viscosity and density?

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Re: pressure drop with few knowns

Post by tsprentall » Thu Mar 04, 2010 11:23 pm

This link will get you your roughness factor; ... d_459.html

Viscosity and density of diesel exhaust at 550-600F may be hard to find. Try soliciting one of the manufacturers like Cummins or Detriot Allison.

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Re: pressure drop with few knowns

Post by admin » Fri Mar 05, 2010 5:10 pm

Here is one table that should be of help:

You will find that it is for certain mixture of flue gas, but it should be of help.

Mixture consist of:

carbon dioxide CO2 - 13%
water vapor H2O - 11%
nitrogen N2 - 76%
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