[medaouarwalid]

Originally Posted by FMDenaro

The temperature will initially increase but then you will get a statistically energy equilibrium (you don't have a room with adiabatic walls). At that point the statistical steady state is a good approximation.

Thank you for your precious help. I will be back 😁

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[medaouarwalid]

Hello professors, i hope you remeber me, i took a period of rest and i am back now. I did some changes on the boundary conditions also for the mesh, i am using the default mesh generating by ansys software with little modification on the size of the elements. I used the kepsilon, k omega and RSM models. Here the results on the axial velocity . Numbers of elements was 3.2 million. What can you Say about the results


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[FMDenaro]

Not bad, the discrepancy is more relevant for increasing z/D. But one should be sure about the experimental measurements.

[BlnPhoenix]

Looking good so far. I think with RANS you can obtain a good solution. As FMDenaro said maybe check measurements again, check the reproducibility of experimental data. From there you can try to make a mesh study. I would say apart from k epsilon the turbulence models look simliar. I would stick to one an try to optimize further. Are you happy so far with the results?

[medaouarwalid]

Originally Posted by BlnPhoenix

Looking good so far. I think with RANS you can obtain a good solution. As FMDenaro said maybe check measurements again, check the reproducibility of experimental data. From there you can try to make a mesh study. I would say apart from k epsilon the turbulence models look simliar. I would stick to one an try to optimize further. Are you happy so far with the results?

Yes i am happy with the results, I will do a mesh study for the three turbulence models . For the experimental data, from the begining i was afraid of the last points because i felt that the mesurements was not so good far away because of some experimental difficulties. After the mesh study i will decide what to do

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[medaouarwalid]

Hi , this is the mesh study for the three turbulence models . Should i do an Other mesh ?


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[medaouarwalid]

As you see velocities results were acceptable, my problem now is with the temperature, all points are the same there is no difference or decrease . Any help please !!

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