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Convergence problem of a thermal stratification tank simulation

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Old   April 25, 2013, 02:22
Question Convergence problem of a thermal stratification tank simulation
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Quentin Hwang
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hey guys,

I have been working on this thing, a small tank with temperature stratification, free surface (free slip boundary in CFX), inlet (opening static pressure), and some contractive outlets (mass flow rate).

water density (varying with temperature), temperature (varying with depth), pressure conditions were set through expressions in cfx-pre. And this simulation is steady.

However, it cannot be converged. See attached pics. I have attempted these time steps: 1 s, 20 s, 50 s, 120 s, 200 s (over flow).

what can I do to get this solved?
Do you guys have any suggestions? Thank u so much for your help.
Attached Images
File Type: jpg 2.jpg (52.8 KB, 16 views)
File Type: jpg 1.jpg (38.0 KB, 10 views)

Last edited by hwangpo; April 25, 2013 at 02:26. Reason: forget something
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Old   April 25, 2013, 08:13
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Old   April 25, 2013, 08:23
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Quentin Hwang
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sorry for this carelessness. thank u so much.
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