Hello,
Dear I am having problems with my mesh for a simulation of flow on a sphere, the case diverges. .
The number of courant reaches a value of 600 and the visualization in paraview tells me that the problem with the mesh is in the vicinity of the sphere, I have tried to follow several recommendations to solve the problem and I can not find the solution to this problem, I have made different meshes and the one that gave me the least mistakes I will attach it so that if someone wants it I can see it, the mesher that I am occupying is salome.
reviewing the listing the warning tells me this.
Criterion 1: Orthogonality:
Number of bad cells detected: 0 -> 0%
Criterion 2: Offset:
Number of bad cells detected: 7822 -> 1%
Criterion 3: Least-Squares Gradient Quality:
Number of bad cells detected: 89 -> 0%
Criterion 4: Cells Volume Ratio:
Number of bad cells detected: 0 -> 0%
Criterion 5: Guilt by Association:
Number of bad cells detected: 0 -> 0%
any contribution will be very grateful.
Greetings.
Meshing warning
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Meshing warning
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Re: Meshing warning
Hello,
I use you mesh and the case run without diverging. The mesh is very coarse and the check quality criteria report some issues. I think that you have to reduce the time step in order to get a Courant ~ 5 or lower.
You can read some guidelines at https://www.code-saturne.org/cms/documentation/BPG.
Best Regards,
Luciano
I use you mesh and the case run without diverging. The mesh is very coarse and the check quality criteria report some issues. I think that you have to reduce the time step in order to get a Courant ~ 5 or lower.
You can read some guidelines at https://www.code-saturne.org/cms/documentation/BPG.
Best Regards,
Luciano
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- Joined: Thu Mar 28, 2019 7:49 pm
Re: Meshing warning
Thanks Luciano,
I have occupied a time step of 0.08 and of 0.01, if I decrease it the simulation time increases too much, with a time step of 0.001 the simulation time is approximately 30 days for which this solution makes me unfeasible, proble with another geometry and a higher time step where the listing does not inform about any warning and in this case the simulation time is prudent with respect to what I need to visualize.
I'm testing with GMSH to see if the problem can be solved
Greetings.
I upload the listing.
I have occupied a time step of 0.08 and of 0.01, if I decrease it the simulation time increases too much, with a time step of 0.001 the simulation time is approximately 30 days for which this solution makes me unfeasible, proble with another geometry and a higher time step where the listing does not inform about any warning and in this case the simulation time is prudent with respect to what I need to visualize.
I'm testing with GMSH to see if the problem can be solved
Greetings.
I upload the listing.
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Re: Meshing warning
Hello,
I attach an example of the flow past an sphere. I use the geometry that you shared and I have created a new mesh. This case with a coarse mesh (aprox 115.000 cellls) took arround 13 min in a laptop to solve 500 time steps with Courant max around 7. I added the listing file in the zip.
I hope that this case can help you.
Regards,
Luciano
I attach an example of the flow past an sphere. I use the geometry that you shared and I have created a new mesh. This case with a coarse mesh (aprox 115.000 cellls) took arround 13 min in a laptop to solve 500 time steps with Courant max around 7. I added the listing file in the zip.
I hope that this case can help you.
Regards,
Luciano
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Re: Meshing warning
Thank you Luciano,
The little experience I see the account apparently, launch the case and converge, my mistake maybe was to guide me a lot by the visualization in para view and not address the problem separately.
So far everything is going well and the simulation is delivering values according to expectations.
Thank you so much.
The little experience I see the account apparently, launch the case and converge, my mistake maybe was to guide me a lot by the visualization in para view and not address the problem separately.
So far everything is going well and the simulation is delivering values according to expectations.
Thank you so much.