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Difference in Results of Simulations

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Old   November 23, 2017, 04:08
Default Difference in Results of Simulations
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Daniel
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Hello there,

i have a little question about my results of two simulations.
These two simulations are nearly the same. The only difference is the blade profile and therefore the Boundary Conditions. But they differ not that much. Everything else is the same, like the CFX Pre Setup.

I've attached 4 Pictures. 2 compare the Temperature Contour and the 2 shows the convergence.
I checked CFX Pre so many times whether there is any big point i missed out. For me, I don't understand why there is such a big difference in the Contour.
I mean they both reached convergence.
Is there anything that could cause this difference?

Thank you for your time and help!

Daniel
Attached Images
File Type: jpg Case 1 RMS.JPG (78.4 KB, 4 views)
File Type: jpg Case 1 Temp.JPG (64.5 KB, 6 views)
File Type: jpg Case 2 RMS.JPG (71.6 KB, 4 views)
File Type: jpg Case 2 Temp.JPG (61.5 KB, 5 views)
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Old   November 23, 2017, 05:19
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Maxim
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Hi,
did you do a mesh independence study and a sensitivity study? Have you read the FAQ section about that? https://www.cfd-online.com/Wiki/Ansy..._inaccurate.3F

Do you judge the different results just by the color of the two screenshots? Because the legend is different. Set them to the same limits to compare.

Which turbulence model are you using? Maybe share your *.ccl file and/or your *.out file.
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Old   November 23, 2017, 05:44
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Daniel
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Thanks for your response Maxim!

No, I didn't do a mesh independence study. I imported the blocking of the first case into the second case and only modified it at the blade.

Yes, that was my first action, just to check if there are any difficulties.
Even when I change the scale, it doesn't look much more similar.
I'm using the SST Model.

I attached a ZIP-Folder with the .OUT and .CCL Files!

Thank you!
Attached Files
File Type: zip CCL and OUT File.zip (59.7 KB, 1 views)
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