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Old   April 30, 2004, 05:11
Default problem withcontinuity residual
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bob
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I have a questions.

First I did simulation and was monitoring the residuals. Contuinty equations reached 10^-5 and epsilon and k recahed 10^4 after say 2000 iterations then I did another 2000 iterations, what I found was the continuity residual suddenly becomes strted incresing 10^-4 and k,epsilon was 10^-6. The question is why does continuity residual increased.
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Old   April 30, 2004, 05:36
Default Re: problem withcontinuity residual
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bob
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Now I have another problem where the continuity,epsilon is flutuating periodically with no sign of convergence at all.

bob

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Old   April 30, 2004, 05:50
Default Re: problem withcontinuity residual
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Tom
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Explain what you are trying to model. Are you modelling steady state?
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Old   April 30, 2004, 07:10
Default Re: problem withcontinuity residual
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bob
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Yes I am modelling steady State. Its about flow around abstacles. bob
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Old   April 30, 2004, 07:17
Default Re: problem withcontinuity residual
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Tom
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Have you tried running this with the transient solver.
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Old   April 30, 2004, 07:40
Default Re: problem withcontinuity residual
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bob
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Hi

why should I run transients when the case is steadyState? Will it be helpful.

Pratap
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Old   April 30, 2004, 15:06
Default Re: problem withcontinuity residual
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CFD Rookie
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Is there any seperation zone (or recirculation zone) after the abstacles? Did you get to check which node produces the highest residual? Is that node located inside the recirculation zone?
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Old   May 10, 2004, 09:52
Default Re: problem withcontinuity residual
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zachi
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Is your case realy steady state or highly turbulent?

At high rates of turbulence a unsteady scheme should be used, because of fluctuation velocities and possible swirls!

regards

zachi
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