I’m working on meshing a complete aircraft geometry and already have the full fluid domain set up. When I attempt a 1D–2D Netgen mesh on the full setup, it takes an extremely long time and often stalls.
If I instead mesh only the aircraft body (without including the farfield and symmetry), the 1D–2D mesh runs quickly and without issues. However, when I then try to generate the 3D volume mesh out the aircraft surface mesh, I get an error stating that the surface mesh does not cover the entire surface.
Has anyone run into this before or have advice on how to handle it?
Hi you have mentioned that you have only surface-meshed (NETGEN 1D-2D) the aircraft body and not the farfield and symmetry.
Sure the system will be able to generate volume mesh from the surface meshes of the aircraft body. But without surface meshes for the farfield and symmetry, Salome has no way of generating the volume mesh.
You will have to generate the surface meshes for the farfield and symmetry first. Perhaps your meshes are too fine or some setting errors have caused your simulation to stall.
To give more context, here are the different methods I’ve tried to resolve this issue:
Created a well defined surface mesh with farfield and symmetry to generate the volume mesh ( Error: surface mesh does not cover the entire surface.)
Used both the 1D-2D-3D and 1D-2D + 3D Netgen options (in both cases, the process often stalls around 90–99%).
Generated a surface mesh for the main body only (excluding symmetry and farfield), which completed in just a few minutes. However, when I included farfield and symmetry, the process stalled again.
For the first part, could you show how you have defined your surface meshes? Also perhaps, have you checked your face groupings to see if all the faces are selected?
the problem is that your issue commes from your geometry. without sharing it, it is diffucult to help. most likelly is that you have really small edges or faces somewhere on the geometry, so edges of the 1D generated, or the faces of 2D. and one or the other has a big impact after, if you have really small edges you will generate really small faces, and then if you have really small faces you will generate a lot of elements and this will ‘stall’ salome.
without the geometry is highly difficult to say. i would recommend to check the surface mesh generated, also you dont mention if you define any parameters of netgen. if you do try increasing the max size. also if your 2D mesh looks really okey, without a ‘hotspot’ where there is too many elements, would try to use for the 3D gmsh instead of netgen 3D. but I insist, this kind of issues is (from my experience) 90% because you have some reaaaally small edges somewhere or a problem with your geometry. if it is too complex, you might need to simplify it, salome meshing, is conformal to the edges of the geometry itself, so it forces the mesh to repsect this, and this while being great, can generate too many elements if the geometry is not correctly defined.
try setting in netgen 1D-2D big elements and then the 3D most probably will not stall.