CFD Online Discussion Forums - [snappyHexMesh] Motobike benchmark case

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Motobike benchmark case

Hi FOAMers!

I am working on Ubuntu 18.04 OF6, and am trying to run the motobike benchmark case, which can be downloaded here. When I run, the output log.snappyHexMesh reads

Code:

Create time



Create mesh for time = 0



Read mesh in = 0.01 s

[0] 

[0] 

[0] --> FOAM FATAL IO ERROR: 

[0] Cannot open etc file "caseDicts/meshQualityDict" while reading dictionary "/home/josh/Downloads/bench_template/run_16/system/snappyHexMeshDict.meshQualityControls"

[0] 

[0] file: /home/josh/Downloads/bench_template/run_16/system/meshQualityDict at line 18.

[0] 

[0]     From function static bool Foam::functionEntries::includeEtcEntry::execute(Foam::dictionary&, Foam::Istream&)

[0]     in file db/dictionary/functionEntries/includeEtcEntry/includeEtcEntry.C at line 127.

[0] 

FOAM parallel run exiting

[0] 

--------------------------------------------------------------------------

MPI_ABORT was invoked on rank 0 in communicator MPI COMMUNICATOR 3 SPLIT FROM 0

with errorcode 1.



NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.

You may or may not see output from other processes, depending on

exactly when Open MPI kills them.

--------------------------------------------------------------------------

I've searched these forums and it appears someone had a similar issue here with a solution in post 5. However, my meshQualityDict (or any other files in that directory) look nothing like what the person describes, so their fix does not work for me.

Any idea how to get the benchmark to run? I really need to check the benchmark for my machine, so any help is so so so appreciated! Also, the motobike tutorial works if I go into tutorials and run ./Allrun.

Hi,

You can also copy directly the content of the meshQualityDict in your snappyHexMeshDict like :

Code:

meshQualityControls

{

maxNonOrtho 65;

maxBoundarySkewness 20;

maxInternalSkewness 4;

maxConcave 80;

minVol 1e-13;

minTetQuality 1e-15;

minArea -1;

minTwist 0.02;             

minDeterminant 0.001;

minFaceWeight 0.02;      // Corrected to 0.02 for the motorBike tutorial

minVolRatio 0.01;

minTriangleTwist -1;

nSmoothScale   4;

errorReduction 0.75;

}

cheers,

Quote:

Originally Posted by john myce (Post 763040)

Hi,

You can also copy directly the content of the meshQualityDict in your snappyHexMeshDict like :

Code:

meshQualityControls

{

maxNonOrtho 65;

maxBoundarySkewness 20;

maxInternalSkewness 4;

maxConcave 80;

minVol 1e-13;

minTetQuality 1e-15;

minArea -1;

minTwist 0.02;             

minDeterminant 0.001;

minFaceWeight 0.02;      // Corrected to 0.02 for the motorBike tutorial

minVolRatio 0.01;

minTriangleTwist -1;

nSmoothScale   4;

errorReduction 0.75;

}

cheers,

Wow, thanks it worked!

Last question: I'm kind of new to OpenFOAM: are these results for the 2 million cell count like the benchmark? I don't want to give bad information, you know?

Well for the motorBike tutorial I think you cannot use it as a benchmark since I do not know if there is actually "reliable" data for it (drag, downforce, ...).

I suppose (but maybe I am wrong) that it is just an example of a case setup for the solver and helps you to understand how it works.

I think it is better to analyse for instance an airfoil where you are sure to find proper data.

Quote:

Originally Posted by john myce (Post 763052)

I'm referring to hardware benchmarking. I recently built a computer and want to see how fast it stacks up to other rigs. One realistic case I am running is very VERY slow (I think it's a BC issue, but uncertain) and so wanted to check my speed against others.

My bad ! I have just found this thread so I think you can do it.

https://www.cfd-online.com/Forums/ha...-hardware.html

Quote:

Originally Posted by john myce (Post 763077)

My bad ! I have just found this thread so I think you can do it.

https://www.cfd-online.com/Forums/ha...-hardware.html

Exactly! Thanks again for your help! You have no idea how much stress it saves me!