CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   Main CFD Forum (https://www.cfd-online.com/Forums/main/)
-   -   Mean Age of Air Convergence (https://www.cfd-online.com/Forums/main/127509-mean-age-air-convergence.html)

msmith December 12, 2013 19:09

Mean Age of Air Convergence
 
Hi all,

I've searched the forum and it seems this is a stupid problem to have, since no one else has it....

I've set up mean age of air in CFX using an additional variable and subdomain etc, however it isn't converging. The age essentially just increases as the iterations increase, even if the momentum residuals have converged...

Ideas?

msmith December 16, 2013 22:59

Ok so advice from support was that MAA equation needs quite a long time to converge because it relies on convecting all the flow from teh inlet through to the outlet. For flows with dead spots, this will take a long time to track the entire fluid path. This can be sped up by using a larger timestep or timescale factor (eg factor of 10).


All times are GMT -4. The time now is 17:25.