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lakeat December 12, 2012 18:00

Engrid, why surface mesh is always rendered as tet mesh even though it is hex?
1. For a simple channel flow, totally structured and hex, imported into engrid, and I am wondering why the surface mesh is always rendered as tet mesh even though it is hex? How can I change this?
2. How can I turn off the mesh, and only choose to view the surface?


atg December 14, 2012 09:25

I have only seen one mention of importing a hex mesh to engrid:

I am currently experimenting with the "create hex core mesh" function, but so far it just deletes my entire existing mesh. I think I may need to be more specific with the starting point - not sure what it is looking for.

lakeat December 14, 2012 13:56

Im going to write my own mesh generator from scratch

atg December 14, 2012 17:34

Ok but if you can do that why not just make a plugin for engrid that will do what you want? Seems like this would be easier than starting from scratch?

lakeat December 14, 2012 17:45

haha, I know, but it seems to me that Engrid has involved too many functions.

I am planning to write a light weighted and more focused on external aerodynamic flows mesh generator.

Just like, since we have the nopad++, why use notepad still? :)

wyldckat December 15, 2012 13:00

Greetings to all!

  1. AFAIK, up to enGrid 1.4 it still handles meshes the way it does best: tetrahedral and prism cells. So it pretty much does what ParaView and foamToVTK usually do: convert everything to the common/simplified mesh denominator: prisms and pyramids ;)
    I think there are plans and already some code for the next version of enGrid to start fully supporting visual display of polyhedral meshes.
  2. If you want to start creating a (yet another) mesh generator... have you taken a look at the already existing ones that are open-source? Besides OpenFOAM's core mesh generation system, enGrid and NETGEN, there's also Discretizer, which I believe is in need of some help coding-wise. It's made in Ruby and it has great potential to go even further...
    A scripted version of enGrid is also welcomed by many, but very few have the time to even look into it...
Best regards,

lakeat December 15, 2012 15:14

Hi again, Bruno

For a single channel mesh, it looks different between importing it in engrid and converted it to vtk and view it then in engrid. And the latter is correct.
Honestly, I have collected more than 30 opensources mesh apps. As I remember one guy once said, mesh generation is easy in a certain sense, however people all want to make it universal and that is the problem.

Have a great weekend!

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