×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Bolt Shell to Solid

Bolt Shell to Solid

Bolt Shell to Solid

(OP)
Trying to formed a bolted connection between a shell and a solid. The stresses aren't important in the shell model, it is only present as a type of compression only boundary surface for the solid element. I have rigid body motion in my model using RBE2's on washer surfaces and a beam element connecting.

I created a smaller sample model to demonstrate my issue. Is there something I am doing wrong, or is it inherently impossible to connect shells and solids in this matter? If so is the model attached "solid bolt surface" with a small solid element glued into the shell an appropriate work around (this doesn't work either as the solid element can't transfer rotation) to not have to solid mesh the entire boundary surface, which would result in roughly an additional 1 million nodes.

Thanks

RE: Bolt Shell to Solid

you`re right, solids have only 3 dof at each node. So I`d make the solid end with a vertical face, with pairs of nodes (at least nodes on the upper and lower surface, yes).

then glue the 2D shell to the 3D solids, and you should get moment continuity.

another day in paradise, or is paradise one day closer ?

RE: Bolt Shell to Solid

Hello!,
Your model is wrong defined, then the error.

First at all when posting a FEMAP model not any reason exist to post as NEUTRAL (*.NEU), simply post your FEMAP model with the regular file extension *.modfem.
We use NEUTRAL file feature when the model need to be exported to an older FEMAP version, for instance we run currently FEMAP V2020.2, then if other user still running old version of FEMAP V12 then exporting NEUTRAL will allow to write the model in version V12 format and will be possible to open in FEMAP V12, but this is not the case.

Back to your model: when you define a BOLT PRELOAD you must be aware that a contact between plate & solid should be defined, if not error for sure: the bolt is preloaded, and the plate is free to move in any direction, then if not contact exist then error, the plate will move as a rigid body, understood?.

Also, the RBE2 should have activated only DOF TX, TY, TZ, the rotations should be free, this is a bolted joint, not welded joint.



Also, mesh your componentes with quality mesh, cost the same effort doing correct mesh or bad mesh.
Also, when solving use integrated solver of Simcenter Nastran, not need to use the option LINKED SOLVER.

This is the model info tree:


And finally, if you define separate load caseS, ONE the SERVICE LOADS and other the BOLT PRELOAD


This is the animation of displacement results with bolt preload + service loads:


Best regards,
Blas.

pd
To learn more visit my FEMAP support page:
http://www.iberisa.com/soporte/femap/tornillos_pre...

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48004 BILBAO (SPAIN)
WEB: http://www.iberisa.com
Blog de FEMAP & NX Nastran: http://iberisa.wordpress.com/

RE: Bolt Shell to Solid

(OP)
Thank you Blas! Do you think you could quickly show how you created that mesh? I'm not quite able to create such a nice mesh outside of the washer using the mesh by surface command. It seems you are able to use an additional control that I am not aware of.

RE: Bolt Shell to Solid

Hello!,
Is very easy: simply prepare the surface geometry splitting in regular regions and the QUAD mesh will be immediate!.
Next copy the 2-D CQUAD4 mesh to the solid face as PLOT PLANAR, and use it a SEED MESH to generate the HEX mesh using command MESH > SWEEP > ELEMENTS using 5 layers, and finally associate the HEX mesh to the solid automatically and you are done!



Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48004 BILBAO (SPAIN)
WEB: http://www.iberisa.com
Blog de FEMAP & NX Nastran: http://iberisa.wordpress.com/

RE: Bolt Shell to Solid

(OP)
Great! Thanks Blas

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper - Implementing a Multi-Domain System
IoT systems are multi-domain designs that often require AMS, Digital, RF, photonics and MEMS elements within the system. Tanner EDA provides an integrated, top-down design flow for IoT design that supports all these design domains. Learn more about key solutions that the Tanner design flow offers for successful IoT system design and verification. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close