Elmer Tutorial 13:Compressible flow passing a step

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Captain Slow
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Joined: 10 Nov 2009, 19:17

Elmer Tutorial 13:Compressible flow passing a step

Post by Captain Slow »

I am trying to re-create the results displayed in the (non-GUI) tutorial 13 using compressible Navier Stokes&the heat equation.

I have followe dthe instruction in the tutorial, and used the step.grd mesh provided, but I do not get the results in the tutorial, in fact I do not get any results at all: the simulation ends (''ERROR:: IterSolve: Failed convergence tolerances.'') in the first iteration of the heat equation (the first NS iteration was carried out succesfully).

I attach my sif and solver log files in the hope of some pointers.
Attachments
case.sif
(2.66 KiB) Downloaded 414 times
SolverLog.txt
(13.06 KiB) Downloaded 380 times
raback
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Re: Elmer Tutorial 13:Compressible flow passing a step

Post by raback »

Hi

Did you take the tutorials files from the nonGUI set in:
http://www.nic.funet.fi/pub/sci/physics/elmer/doc/

-Peter
Captain Slow
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Joined: 10 Nov 2009, 19:17

Re: Elmer Tutorial 13:Compressible flow passing a step

Post by Captain Slow »

I constructed my own sif file from the instructions in the tutorial and the step.grd file I found in the distributio, albeit from the GUI section. In any case my test with a self constructed (in gmsh) step have also failed...
Captain Slow
Posts: 72
Joined: 10 Nov 2009, 19:17

Re: Elmer Tutorial 13:Compressible flow passing a step

Post by Captain Slow »

So, I got a bit futher with this, though I must admit to feeling as though I shouldnt trust the convergence of the heat equation:
Convergence.png
Convergence.png (737.05 KiB) Viewed 5159 times
As an aside, if I set

Code: Select all

Compressibility Model = "Thermal"
what does this do?
raback
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Re: Elmer Tutorial 13:Compressible flow passing a step

Post by raback »

Hi

The convergence shows the relative change and for heat equation this is quite small since there is typically a large offset (which there isn't for the N-S). Hmm. perhaps it would alternatively make sense to compare the change to |x-<x>| rather than to |x|.

-Peter
foadsf
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Re: Elmer Tutorial 13:Compressible flow passing a step

Post by foadsf »

Hi everyone,

Any idea where I can find the FlowStepCompressible folder of example 11 non-GUI on this tutorial? I wish all these examples would be in one place in their own GitHub repository along with the documentation. Or at least the PDF would point to the right folder containing the example folder.

P.S. Nevermind. Found them here.
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