LINEAR STATIC ANALYSIS for a wing made up of ribs(surface) and spars(solids)
LINEAR STATIC ANALYSIS for a wing made up of ribs(surface) and spars(solids)
(OP)
hello guys,
I was trying to do a linear static analysis for a part of a wing made up from 3 ribs drawn as surfaces and represented as 2D thin shell, on the other hand, the leading and trailing edge as well as the front and rear spar are solid and represented in Patran as 3D solid. I tried first the normal modes analysis and I got reasonable results, but for the linear static analysis, I am not getting any results. Any idea, how to fix this issue? note that the wing was imported from a Parasolid file, I suspected first to be a geometry problem, so I tried to draw a quick sketch on Patran itself having one surface and one solid and I tried to do the analysis with no luck as well. I am not sure if the problem is that I have a mix of surface and solid together.
I attached a picture of the model.
I would really appreciate your help!
Thank you in advance!
Regards
I was trying to do a linear static analysis for a part of a wing made up from 3 ribs drawn as surfaces and represented as 2D thin shell, on the other hand, the leading and trailing edge as well as the front and rear spar are solid and represented in Patran as 3D solid. I tried first the normal modes analysis and I got reasonable results, but for the linear static analysis, I am not getting any results. Any idea, how to fix this issue? note that the wing was imported from a Parasolid file, I suspected first to be a geometry problem, so I tried to draw a quick sketch on Patran itself having one surface and one solid and I tried to do the analysis with no luck as well. I am not sure if the problem is that I have a mix of surface and solid together.
I attached a picture of the model.
I would really appreciate your help!
Thank you in advance!
Regards





RE: LINEAR STATIC ANALYSIS for a wing made up of ribs(surface) and spars(solids)
Open the F06 file in a word processor (Notepad or Wordpad etc.) and search for the word "Fatal". If errors are found, it should also list the error codes which will tell you further about issue Nastran encountered during the run.
Also AFAIK, there will be displacement incomptability between shell & solid elements. Solid elements only support the 3 translations (TX, TY & TZ) but not rotations while shell elements support all 6 DOFs. One way to overcome this is to use glue contact between shell & solid elements. The other way is to use Rigid elements to connect between shell & solid elements. I am assuming you are aware of the above and used appropriate procedures since your 103 run did not throw up any discrepancies.
RE: LINEAR STATIC ANALYSIS for a wing made up of ribs(surface) and spars(solids)
It was a contact problem, I made all the parts deformable and in the contact table I made the corresponding parts touch, and that solved the problem.
I finally got my results, thanks for pointing out on the contact issue.
I really appreciate your help!