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Problem in fireFoam - Co vs. T_max

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Old   June 5, 2017, 14:16
Default Problem in fireFoam - Co vs. T_max
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Hello,

i'm trying to get used to the fireFoam solver in OF 4.X. I created a small test case of a rectangular shape. I used the 3Dfirepool tutorial test case files and set it to laminar. Now if i simulate 5 sec of real time and try different maxCo, i get different T_max temperatures at the end of the run (=5 sec).
In total the variance is almost 380K between my max Co of 0.5 and the min Co of 0.01. (see graph) Also i get non strictly growing temperatures T_max with decreasing maxCo, which i think is odd.

1) Can anybody suggest why the difference in combustion temperatures exists?
2) Why is there "hole" around maxCo 0.1 and 0.03?
3) Most importantly, which Time step should i choose?
Attached Images
File Type: jpg fireFoam.jpg (88.8 KB, 20 views)

Last edited by BlnPhoenix; June 14, 2017 at 05:24.
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Old   June 12, 2017, 12:32
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Have you tried a more refined mesh or running it to 10s to see if that changed anything?

Disclaimer, I have very little experience with fireFoam. I find this interesting.

Joshua
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Old   June 12, 2017, 13:35
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Thanks for your suggestion, Joshua! I will try to refine the grid and check back.
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