×
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!

*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

Which nastran can solve surface-surface contact?

Which nastran can solve surface-surface contact?

Which nastran can solve surface-surface contact?

(OP)
The question is the same. Additional: Which is the best?
(Speed, accuracy etc.)

Irwin

RE: Which nastran can solve surface-surface contact?

NEiNastran can.  Their website is the ad above.  They have many examples and animations on their site.  MSC uses MARC which is not bad but NEiNastran is better IMHO (and costs a fraction of what MSC charges).  It is also integrated into FEMAP which MSC's is not.  Check out the NEiNastran website.

RE: Which nastran can solve surface-surface contact?

MSC.Nastran is integrated in FEMAP under the label MSC.Nastran for Windows.

RE: Which nastran can solve surface-surface contact?

(OP)
I heard about NE NASTRAN. I know all NASTRAN is integrated in FEMAP. A question is: MSC, NX etc NASTRAN knows or not the surface-surface copntact. I had seen lots of picture about contact analysis with these NASTRAN, but upto now I did not find element type of it!

Irwin

RE: Which nastran can solve surface-surface contact?

Irwin,

Contact is generally a manipulation of a Truss element for which you can designate a stress-strain curve.  Basically, you define the stress-strain curve in such a way that it has no modulus of elasticity (i.e. a flat stress-strain curve) until you reach a strain nearly equal to the length of the element.  Once you shortened the element to a certain length, the stress-strain curve then indicates a large modulus.  If you manually create this elements, be careful that you don't change this stress-strain curve too rapidly or the problem may not converge.

Many FE packages have incorporated this "curve truss" element and predefined the stress-strain curve renaming the element a "contact" element.  You generally have to be in a non-linear analysis method to use this feature.  I know Algor and NENastran have it.  I'm also pretty sure that COSMOS can do it.  Not sure about MSC Nastran, but do agree that it is in FEMAP.


RE: Which nastran can solve surface-surface contact?

To clarify... FEMAP supports surface to surface contact using arbitrary geometric surfaces or element faces for NEiNastran, ABAQUS, LS-Dyna, and ANSYS.  This form of contact is the most general and the easiest to setup.  MSC and NX support in FEMAP is for gap contact (which does not support general large displacement sliding or multi-body contact) and slide line (which does support large displacement sliding in one plane or direction but is very tedious to set up).

The truss element that is discussed above is simply the gap element in nastran and no stress-strain curve is required.  A simple rod or truss element can be set up this way as described but this is not necessary in nastran.  For undulating surfaces the setup for gaps is very time consuming requiring a different set of parameters for each element.  

Surface contact is the best solution.  It is the easiest to set up and with few exceptions will handle most contact scenarios.  

RE: Which nastran can solve surface-surface contact?

Agreed.

Garland E. Borowski
Borowski Engineering & Analytical Services, Inc.

RE: Which nastran can solve surface-surface contact?

I believe that MSC supports surface-to-surface in the Nonlinear+ module. That is Marc implemented inside Nastran. As for NX I'm sure. NX is based on MSC but before Marc was implemented.

Surface-to-surface with gap elements is possible but not a good solution. It depends a lot on your typical model.

RE: Which nastran can solve surface-surface contact?

Yes, but that MARC interface is not in FEMAP.  It may be added later but I really doubt it.  It would be more likely that NX comes up with something similar to what NEiNastran has and that is added to FEMAP.

RE: Which nastran can solve surface-surface contact?

I can't test the functionality since I don't have the nonlinear+ module. But, there is a surface-to-surface contact functionality in FEMAP that is associated to Marc.

RE: Which nastran can solve surface-surface contact?

Yes, it is there but that is for MARC, not MSC.Nastran 2005.  MSC has hidden the MARC solver in their SOL 600 add on which makes it appear as part of Nastran.  What ever support is in FEMAP is for the original MARC product that existed before MSC aquired them.  

I still recommend NEiNastran because it is easy to set up and works.  Certainly MARC is a capable product as well.

RE: Which nastran can solve surface-surface contact?

OK, like I said I can't test it to verify either way. So I just take your word for it. I know that SOL 600 runs Marc based on a Nastran Bulk data deck, but I got the impression that surface-to-surface contact was included since it is mentioned in the documentation.

Wrong again :-(.

Thomas

RE: Which nastran can solve surface-surface contact?

(OP)
Additional question is the FEMAP itself. The FEMAP was bought by ideas, the ideas was bought by UG. Upto the 8.3 we got always newer and newer version. After 8.3 nothing is happened. Does anybody know why?

Irwin

RE: Which nastran can solve surface-surface contact?

Thomas, to clarify MSC does have surface to surface contact using MARC (now SOL 600) but bulk data entry format to support it is not available in FEMAP.

Irwin, FEMAP v9 will be released shortly (as I am told) and has a lot of new features and a completely new look and feel.  UGS owns FEMAP.

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

eBook - The Future of Product Development is Here
Looking to make the design and manufacturing of your products more agile? For engineering and manufacturing organizations, the need for digital transformation of product development processes just became more urgent than ever so we wanted to share an eBook that will help you build a practical roadmap for your journey. 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