Quick question: Does this residual plot mean the presence of unsteadiness?

nvarma · April 1, 2015, 11:48

Hi, (see attached image)
This is from a steady state run for natural convection. Does this mean there's a vortex near the boundary or somewhere within the flow field, because of the oscillatory behavior of the residuals?

So should I be doing a transient analysis?

2_steady.jpg

aalzoubi06 · April 1, 2015, 15:00

Please run the case for some few thousands of iterations to see what will happen later.
Besides, it is good to monitor at least one relevant variable with time and see if there is a transient behavior in its value. Please note that in order to say that you solution is converged one should check the mass imbalance (difference between mass flow rate at inlets & mass flow rate at outlets).

All the best and success

April 1, 2015, 11:48	Quick question: Does this residual plot mean the presence of unsteadiness?	#1
nvarma Senior Member nm Join Date: Mar 2013 Posts: 100 Rep Power: 13	Hi, (see attached image) This is from a steady state run for natural convection. Does this mean there's a vortex near the boundary or somewhere within the flow field, because of the oscillatory behavior of the residuals? So should I be doing a transient analysis? 2_steady.jpg

April 1, 2015, 15:00		#2
aalzoubi06 New Member Ahmad Al-Zoubi Join Date: Nov 2013 Posts: 17 Rep Power: 13	Please run the case for some few thousands of iterations to see what will happen later. Besides, it is good to monitor at least one relevant variable with time and see if there is a transient behavior in its value. Please note that in order to say that you solution is converged one should check the mass imbalance (difference between mass flow rate at inlets & mass flow rate at outlets). All the best and success nautilus88 likes this.

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