Friction factor (Cs)
 

What is the value of surface roughness Cs (Friction factor for walls) for Brick wall in a Flue stack.

Is there a correlation between the Surface roughness Cs in fluent and the actual surface roughness E. For cement the actual E is 0.9 to 9 (mm), while for steel it is 0.05.

In Fluent the Value of Cs can be varied from 0 to 1 only.

To Add More, it is Flue gas flow analysis of a boiler chimney with a apporximate height of 200 meters. The Chimney is brick lined and cemented.
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