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#1 |
Senior Member
Hannes Kröger
Join Date: Mar 2009
Location: Rostock, Germany
Posts: 124
Rep Power: 18 ![]() |
Hello,
I have implemented a new boundary condition which is similar to the existing "timeVaryingUniformFixedValue". It allows not only the specification of a uniform fixed value for several time instances but also of full boundary fields. I have used this boundary type to prescribe a boundary velocity to the LES solver (oodles) which has a certain mean value and RMS. When I run the calculation everything is fine and seems to be working well. The problem is with the results from the averaging procedure in the LES solver. I expected to get the same RMS value on the inlet patch as I had prescribed. But what I get is different. Especially the RMS of the patch-normal velocity is factor 2.5 to high. I cannot say something about the RMS in the internal field of the domain, but they may be ok. I was wondering if there is an issue with my time interpolation and I checked, but it is all ok. Furthermore, I have implemented the same averaging procedure (for Umean and R) as in oodles directly into my boundary condition class to average the boundary field without going through the fvPatchField-mechanism. Then I get the expected result! What may be the reason for the different results? Does anyone have an idea? Best regards, Hannes Btw: if someone wants to have a look at the code, it can be found here: http://palamedes.fms.uni-rostock.de/...FixedValue.tgz
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