Make meshing more efficient

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1

Hello!

Is there a way to force the mesher to have a mimmium edge length outside a geometry primitive?‘’

I feel like alot of cells are wasted in refinement of the empty regions in the corners of the flow region.

Or is there a way I can make the simulation more efficeint? Each sim currently costs around 100 core hours

I’m using the hex dominant mesher with fine meshing,

Thanks in advance for any help!

Project link is here https://www.simscale.com/workbench/?pid=1541821772631747284&mi=geometry%3A516&mt=GEOMETRY

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2

Hi there,
Thank you for posting on the forum and sharing your project!
We will go through the project and get back to you soon :slight_smile:

3

Hi there,
Can you tell me why are you using hex dominant mesher as opposed to the standard algorithm mesher? It’d be helpful to know this in order to proceed :slight_smile:
Using the standard mesher gives you almost the same quality mesh with any refinements and takes up only a few core hours.

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I’m sure the mesh quality can be improved by adding refinements in the geometry primitive regions as well.

4

You have to use the Hex-Dominant Parametric meshing algorithm.

  1. What I recommend is that you set your Background Mesh Box (BMB) sizing to integer values in meters.
  2. Then you set the Bounding Box Resolution in the HexDomPara parameters to the number of meters your BMB is in each direction.
  3. Now, all your mesh refinements will have cell sizes for their levels that will start at Level 0 is 1m, Level 1 is 0.5m and so on down in a binary progression.

I find this helps greatly because you can make your BMB quite large to reduce BMB wall interactions at very small cell count penalty.

Here is a current project which uses that process: LazairFoil by DaleKramer | SimScale

I am not saying the the Standard mesher does not have any value as it is simple to use but I personally still have concerns about the precise accuracy of using TET cells for CFD based projects AND I did answer your exact topic query :wink:

1 Like
5

The standard mesher is very inefficeint at preserving the geometry at high fineness, these are supposed to be vortex generators but they got mangled by the mesher

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I might add a region refinement there

6

Hey Dale!

Would the mesh settings for the Foil project you posted work for a larger scale simulation? I have to simulate a vehicle around 5mx1.8mx1m and its pretty difficult getting good meshes

7

Yes absolutely, 1m level 0 is great even for large aircraft.

You will be able to precisely mesh you vortex generators too :slight_smile:

I have never needed past Level 11.

1mLevel0-expanded to level 11

Here are a couple great links that could help you: