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the continuity residual is not converging

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Old   March 18, 2017, 00:23
Default the continuity residual is not converging
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Cakov
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file:///C:/05_AS002BEME5/mecca/mecca02_files/dp0/FLU/Fluent/SYS.2-5-00248.jpg

i am simulating a car park with jet fans. both inlet and outlet of the fans are labeled with fans(boundary condition). the pressure jump at the outlet is 700Pa.
a steady state, standard k-e turbulence, pressure-velocity is coupled.

how to reduce the continuity residuals? pls help me!
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Old   March 18, 2017, 06:25
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Behrooz Jamshidi
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Hi
If your setup is correct then try increasing your mesh density in high gradient regions.
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Old   March 19, 2017, 05:02
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What's your mesh quality like?, I've generally found that continuity is particularly sensitive to the quality of the mesh and won't converge when the other quantities will.

p.s.

With images I find it's best to upload then to a storage website, like Imgur, first and then link them here. I don't think you can directly upload to to here (anymore?).
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Old   March 19, 2017, 06:53
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Quote:
Originally Posted by CFD-fellow View Post
Hi
If your setup is correct then try increasing your mesh density in high gradient regions.
i am not very sure about the setup. most of it i just leave it at default.
But i did increase the number of mesh but the continuity residuals is still at 10^-2
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Old   March 19, 2017, 07:02
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Quote:
Originally Posted by GregCFD View Post
What's your mesh quality like?, I've generally found that continuity is particularly sensitive to the quality of the mesh and won't converge when the other quantities will.

p.s.

With images I find it's best to upload then to a storage website, like Imgur, first and then link them here. I don't think you can directly upload to to here (anymore?).
My mesh size function is proximity.
Relevance center is fine.
Smoothing is high
Transition is Fast
Span angle center is fine

The rest is set as default.
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