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UDF for thermal conductivity relation of nano fluid |
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April 21, 2016, 03:41
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#21 |
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Senior Member
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Idea: Initialize your problem, load the UDF, and (without doing any iterations) plot your thermal conductivity and viscosity. Analyze the values that you see, are they what you expect?
If you see NaN or -1e30 or 1e30, it is obviously wrong. Then, find the error in your code. |
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September 26, 2016, 08:41
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#22 |
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NGP
Join Date: Mar 2016
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Hi
thanks for your help I have the following massages from fluent solver: divergence detected in AMG solver: temprature -> increasing relaxation sweeps! you may try the enhanced divergence recovery with( rpsetvar ' amg/ protective -enhanced? #t) i attached the picture of massages. I need your advice. many thanksAttachment 50718 |
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September 26, 2016, 08:49
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#23 |
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Look at my message from April 21, 2016 08:41.
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September 26, 2016, 09:39
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#24 |
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NGP
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hi
plot ? where is this ''plot command'' for conductivity"? is it in Result bar of fluent"? |
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September 26, 2016, 09:58
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#25 |
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You should know that you can show results in Fluent...
Did you never make a picture of velocity??? Did you never make a picture of pressure??? If you did not: please follow some tutorials first. If you did: do the same, but then with viscosity in stead of velocity. |
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September 26, 2016, 11:23
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#26 |
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NGP
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1) yes. the the thermal conductivity is zero ... every where!!
and viscosity has a constant value 8.9e-4 2) when checking the case topology... -this case has both inlet and outlets -pressure information is not available at the boundaries. are these 2 issues makes any problem for my set up? |
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September 26, 2016, 11:44
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#27 |
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NGP
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Hi
this is what i try to write in my code: ImageUploadedByCFD Online Forum1474900809.891608.jpg the 2nd picture is what i wrote: ImageUploadedByCFD Online Forum1474900978.125366.jpg this code is for conductivity. i may have some problem in the code writing please help me thanks navid |
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September 26, 2016, 11:44
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#28 |
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Senior Member
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Your problem is the thermal conductivity. It is zero. So that is why your temperature calculation immediately goes wrong.
The problem is in your udf. It gives zero as a value. Fix that! |
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September 26, 2016, 11:47
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#29 |
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NGP
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yes Pakk
there is a problem with the code. |
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April 1, 2017, 04:02
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#30 | |
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New Member
HASAN
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Quote:
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