slow convergence of bounded CDS

CFDnerd · August 4, 2018, 17:22

Hello fellow CFD users,

I am running a transient analysis in CFX with SAS SST. During my experimentation, I have observed that the bounded CDS results in a very slow convergence compared to the run "un-bounded" CDS option. I would like to understand reasons of such behavior.

ghorrocks · August 4, 2018, 20:14

This is unexpected. I cannot explain that.

But each simulation is different and issues as nebulous as stability are never simple. Your case might be a rare situation where the general rule does not apply.

August 4, 2018, 17:22	slow convergence of bounded CDS	#1
CFDnerd New Member CFDnerd Join Date: Aug 2018 Posts: 5 Rep Power: 7	Hello fellow CFD users, I am running a transient analysis in CFX with SAS SST. During my experimentation, I have observed that the bounded CDS results in a very slow convergence compared to the run "un-bounded" CDS option. I would like to understand reasons of such behavior.

August 4, 2018, 20:14		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	This is unexpected. I cannot explain that. But each simulation is different and issues as nebulous as stability are never simple. Your case might be a rare situation where the general rule does not apply. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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