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Old   August 30, 2012, 20:12
Default convergence problem
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navid
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Hi all,

I have problems in getting convergence for an unsteady simulation. the continuity residuals do not fall down below 4*10^-3.
changing URF's does not make a difference. what surface monitors can I use to check convergence? since there is no steady state solution for my problem, every quantity like pressure and velocity will change in domain. how can I deduce convergence from surface monitors? Below is the picture of the residuals.
any ideas?
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Old   August 31, 2012, 15:48
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Jared Brewer
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It is going to depend on your simulation. Typically, I monitor mass/volume flow rates across boundaries. Unsteady simulations are usually a little more difficult to judge convergence based on residuals.
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Old   September 1, 2012, 03:07
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navid
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I don't have any mass flow rate. my problem is a bubble collapse simulation. I cannot check pressure or velocity in domain since it is changing constantly. I don't now if my simulation is converged or not?
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