necking analysis with patran and md nastran 1

[Charoenpon555]

Hi
I tried to analysis necking of specimen by using patran and md nastran. I modeled its material as elastoplastic and set solution type as nonlinear static with default data in its solution parameters. But not work! Could anybody guide me how to solve this type of problem by patran and md nastran.
Thank in advance
Charoenpon

 

[ZeroExperience]

What version of Nastran are you using? MD Nastran 2010, MSC Nastran 2010, etc? Which Solution Sequence are you using, SOL 106, 400 or 600?

I saw a tutorial on this somewhere, I'll try to dig it up.

 

[ZeroExperience]

I found an old workshop that walks you through a very similar problem. This problem uses SOL 600 I believe, but I would try to use SOL 400 later on since it is the preferred SOL for nonlinear analysis in MSC/MD Nastran.

https://docs.google.com/presentation/d/1ALjySIGL7T1MQNrqa5w-Ru-_gHaviWlC1SNP_krzteo/edit

 

[Charoenpon555]

Thank a lot ZeroExperience
I currently use md nastran 2008, for sol600 is good for me to solve this problem type, sol106 (default of nonlinear static) is not work but i have never try sol400 before. Is sol400 better than sol600 for inplicit nonlinear?

 

[ZeroExperience]

For this case, both SOL 400 and SOL 600 will do fine. SOL 600 starts another solver called Marc to perform the nonlinear analysis. SOL 400 is genuine Nastran, Nastran does the number crunching and not Marc, and contains many of the technologies found in SOL 600. SOL 400 will be sufficient for numerous applications.

I would stay away from archaic SOL 106 unless your boss makes you learn it. Trying to do contact analysis in SOL 106 is a pain from what I heard. I am sure with a lot of time you can pick up SOL 106.