Nusselt number

Fun_Doge · October 4, 2016, 03:57

Hi!

I am working with the postprocessing of a case, where I follow a paper and compare my results with their. Our meshes are somehow similar but the total Nusselt number does not agree. Mine has a higher value so I was going to ask what's behind this. Any comment will be helpful since I'm a beginner.
Thanks!

Chris_321 · October 17, 2016, 02:06

Hi,

check the Nu parameters for equivalence in your simulations and the paper:

characteristic length
thermal conductivity

If they are the same you have a problem with the convective heat transfer. Next thing to do would be check if your mesh is convergent, to do this plot the Nu Number in dependence of the global mesh refinement.

If your mesh is convergent and your parameters are equal it could be a problem with the boundarys or your residuals.

October 4, 2016, 03:57	Nusselt number	#1
Fun_Doge New Member Sarah M Join Date: Oct 2016 Posts: 8 Rep Power: 9	Hi! I am working with the postprocessing of a case, where I follow a paper and compare my results with their. Our meshes are somehow similar but the total Nusselt number does not agree. Mine has a higher value so I was going to ask what's behind this. Any comment will be helpful since I'm a beginner. Thanks!

October 17, 2016, 02:06		#2
Chris_321 Member Christian Join Date: Sep 2013 Location: Germany Posts: 88 Rep Power: 12	Hi, check the Nu parameters for equivalence in your simulations and the paper: characteristic length thermal conductivity If they are the same you have a problem with the convective heat transfer. Next thing to do would be check if your mesh is convergent, to do this plot the Nu Number in dependence of the global mesh refinement. If your mesh is convergent and your parameters are equal it could be a problem with the boundarys or your residuals.

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