I drew a fuselage section as a flat multi-body/surface part and used the flex command to get the correct radius. This model is being sent into ABAQUS for analysis as a Parasolid (x-t). To help aid in the placement of rivets once in ABAQUS I am using the split curve to create lines to seed my mesh with. Rivets are placed at mesh vertices and with the split line + seed intervals I can force the mesh to have nodes in the correct locations. I am able to create all the correct rivet lines on my flat part but once I use the flex command the surface becomes single faced. I tried using the wrap command but haven't gotten it to work on anything other than the skin surface. I've attached some screen shots of the model. The third image appears to be multi-faced but it is not.... some kind of graphical error due to the close separation of the skin surface to the stringers and frame. Thanks in advance.
- Mike
If I were doing the analysis I would spend the time to get the CAD right before handing it off to Abaqus. Abaqus and all FEA packages are very picky with geometry being dead-on. Since you called out that the report only states a radius for the panel I believe the geometry is simply an extrude and a revolve without merge bodies.
Alternatively in Abaqus you could model the flat panel with tied constraints between the stringers in addition to the rivets and then conform it to a cylinder by utilizing a pressure load and contact. Then use an anneal step to remove any residual stresses. Then apply the loads you intended and remove the tied constraint.
Personally the first option sounds much easier to me and I'm sure this forum can help. If you choose the latter option I suggest asking for help here http://www.eng-tips.com/threadminder.cfm?pid=799.
I hope this helps.
Rob Stupplebeen