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Old   September 21, 2015, 08:22
Default Residuals vs convergence
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So i've implemented residuals (rms residuals) and also convergence between two iterations (rms convergence). I get oscillating residuals but all below 1e-5 whereas my convergence is monotonically decreasing. The velocity profiles predicted look okay. So which should i use as my stopping criteria, the residuals or the convergence?
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Old   September 21, 2015, 08:53
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Originally Posted by kabz View Post
So i've implemented residuals (rms residuals) and also convergence between two iterations (rms convergence). I get oscillating residuals but all below 1e-5 whereas my convergence is monotonically decreasing. The velocity profiles predicted look okay. So which should i use as my stopping criteria, the residuals or the convergence?
difference bewteen two iterations is not meaningful for the real convergence
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Old   September 21, 2015, 09:03
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difference bewteen two iterations is not meaningful for the real convergence

Can I use both? If i was to rely on residuals alone, my algorithm would stop within 2 or 3 iterations (since they are always below 1e-5)
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Old   September 21, 2015, 10:31
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Can I use both? If i was to rely on residuals alone, my algorithm would stop within 2 or 3 iterations (since they are always below 1e-5)
the residual must diminuish below such value
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