operating density in buoyancy driven flow
 

This is a question on the use of the operating density. I have a buyoancy driven flow in an open chemney with heated walls. I always used the incompressible ideal gas density for the air and an operating density equal to the volume average of the density over the whole chemney. However, I just tried to unselect the operating density option and instead of going up, the major part of the flow goes down. The result is therefore very different. Could anyone please explain me which option I should choose ?

Thank you !

Marie-Anne

Re: operating density in buoyancy driven flow
 

Sounds as if you're using a commercial code. Which one?

Re: operating density in buoyancy driven flow
 

Hi, I am using FLUENT6.2.16. But maybe it is the same in every commercial codes ?