Reply To: Need help with understanding meshing procedures

[peteroznewman]

The reason to turn the spars and ribs into surface geometry is to make them easy to mesh. Deformation results will be comparable to a hex mesh.  Stress results from shell elements will have a lot fewer stress singularities than the hex element mesh which will make evaluating stress simpler.  The skin over the ribs should also be surface geometry and the real pressure distribution can be applied to those surfaces.

I don't understand why you think a surface model would not be appropriate for the spars and ribs. Perhaps you can insert a few images to show an example where only a solid body would work. I can understand if you have detailed fittings to connect thin structures like the skin and the ribs together or a detailed fitting where the spars connect to a solid fitting in the fuselage. There is no problem having a mixed solid/surface model to get both of those.

To have shared topology between some geometry such as spars and ribs, put them in one component below the top level assembly. Open that component and use the Share button.  Then from the top level assembly, add another component and move the solid bodies for fittings into that component. Those will not share topology with the spars and ribs. Once that is read into Mechanical, you can use various methods such as a Beam Connection to simulate a bolt connecting the edge of a hole in the spar surface to the face in a solid representing the threaded hole in a fitting.