Can someone let me know if these residuals look really odd?

UWBCFD · February 26, 2016, 18:59

My system involves two partially closed cell zones of air with adiabatic boundary conditions. The cell zones are in contact and are allowed to interact at that contact region. Each cell zone starts out at different initial temperatures and is undergoing a transient, density based study with full buoyancy effects and viscid flow.

Any thoughts on these residuals?

LuckyTran · February 27, 2016, 08:38

That is more or less how residuals behave in a transient simulation. What do you think is odd?

Residuals tend to decrease (hopefully) with each iteration. At the next time-step the most recent solution is used as the initial guess (which is not the solution to the new time-step) so residuals jump up on the first iteration of subsequent time-steps.

February 27, 2016, 08:38		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,675 Rep Power: 66	That is more or less how residuals behave in a transient simulation. What do you think is odd? Residuals tend to decrease (hopefully) with each iteration. At the next time-step the most recent solution is used as the initial guess (which is not the solution to the new time-step) so residuals jump up on the first iteration of subsequent time-steps. edd313 likes this.

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