Boundary layer issues
 

Hello, foamers


I'm having trouble adding boundary layers to my mesh. I've been tinkering with the layer controls as well as reading related threads in here, but I wasn't able to create the boundary layer. I tried attaching my sHMDict, blockMeshdict and the outputs but it didn't let me, for some reason, so I've put them on pastebin.

sHM: https://pastebin.com/BSfdWWkv
blockMesh: https://pastebin.com/ub3iKxNC
layer output: https://pastebin.com/tvAqjd3t


Does anybody know what's wrong? Thanks in advance.


Lucas

Hello Lucas,


You already have alotof cells having pyramid volume less the 1e-13. Try to use a much smaller value for pyramid volume (may be like 1e-20). Also you are using relative size false. Are you sure your mesh cell size is in the same range?


Regards

Hello! Thanks for the reply!

I was using "relativeSize True" before so I decided to try it the other way. My geometry is an aneurysm about 5cm long.

I tried out your suggestion and unfortunately it didn't yield any different results.

Here's the output: https://pastebin.com/theQhMTX

Also I have attached what a slice of my geometry looks like after snap, but before layers. (After I run with addLayers on i get that exact same result)


Regards,

Lucas

How is your mesh quality before adding layers with pyramid volume <1e-20. May be you can try with relative size true starting with one layer. If you like, you can upload your case here and I can try myself (I will be able to test on manday).


Regards

Hi,


I've uploaded my case here: https://www.dropbox.com/s/1x24dhqtig...urysm.zip?dl=0


I ran checkMesh and it didn't give me any errors. I'll try changing other settings. Thanks for the help!

Use default meshQualityDict for castellation and snap.
Try to use following meshQuality settings for only 'layer generation process'

maxNonOrtho 180;
maxBoundarySkewness -1;
maxInternalSkewness -1;
maxConcave 180;
minVol 0;
minTetQuality -1e30;
minArea -1;
minTwist 0.002;
minDeterminant 0.001;
minFaceWeight 0.05;
minVolRatio 0.01;
minTriangleTwist -1;