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February 23, 2011, 02:05 |
residual oscillations
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#1 |
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hi im relatively new to cfx, and im trying to model a can combustor flow with a mixture of propane and butane as the fuel. im getting steady residual oscillations in the solver after a 100 hundred iterations. im using EDM, k-e for turbulence. can anyone tell me why this is happening - i've tried changing to physical timescale, increasing the timestep, decreasing it,but nothing is working. id be really grateful for any help. thanks.
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February 23, 2011, 16:45 |
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#2 |
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Glenn Horrocks
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February 24, 2011, 13:43 |
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#3 |
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Did it converge without combustion?
What does the mesh quality report in the outfile say?
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February 28, 2011, 01:34 |
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#4 |
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@ghorrocks, i ve read through that already.. and though the timescale alteration works for some curves, the others are still steadily in a straight line. is it possible i have to change my boundary conditions? i have converged similar models with the same BCs.
@joey: i havent tried running it without combustion. i will do that now and see. |
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February 28, 2011, 06:36 |
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#5 |
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it doesnt converge without combustion either - what does that mean?
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February 28, 2011, 16:42 |
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#6 | |
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Glenn Horrocks
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Quote:
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March 1, 2011, 14:25 |
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#7 |
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If it does not converge without combustion, something basic is wrong. Follow the recommendation from Glenn.
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