No result for Nastran in CAD 2015 , takes lot of time , iterations are more .

[Anonymous]

Hi ,

I am facing serious problem with Nastran in CAD 2015 , I have Inventor (Version 2014) model with 30-40 parts ( small parts). .

I have assigned all material , physical , constraints & loads, Non continuous mesh is also successful. Provided manual contacts to make sure all contacts are considered. But when we select run option for the Nastran in CAD output , it goes for more than 100 thousand iterations , still then we have not received any output results.  

please find attached URL link to download the model & also the screenshot of progress.

Request your assistance at the earliest .

Many thanks & Regards,

Jagadish Megadi

[Andrew.Sartorelli · Accepted solution]

Hi Jagadish,

I believe this is the same model that my colleague Sachin has shared with me. After examining the model it appears that the contacts in the model are set to separation rather than bonded. Once you change to bonded the model should run rather quickly.

Regards,
Andrew

[Anonymous]

Hi ,

As you have the model already , I request you to send the result or output file for the same.

Many thanks & Regards,

Jagadish Megadi
Assistant Manager – Design
Tenova Delkor India

[Andrew.Sartorelli]

Hi Jagadish,

Because of the size of the FNO file, the result format that we use for Nastran In-CAD, it is not possible to easily send this by email. I simply removed all of the contacts you had manually defined and used the automatic bonded contact you had previously defined.

Regards,

Andrew

[Anonymous]

Hi Andrew ,

Please share some images or drop it on www.dropbox.com

Many thanks & Regards,

Jagadish Megadi
Assistant Manager – Design
Tenova Delkor India

[Andrew.Sartorelli]

Hi Jagadish,

I've attached a zip of the assembly file here. It is only the assembly file, so you will need to place it in the same directory as all the part and project files to review it.

Regards,

Andrew

[Anonymous]

Hi Andrew ,

Thank you for the feedback ,

Please refer 1st attachment wherein we have provided the contact as you suggested .
In Nastran in CAD 2015 , General is equivalent bonded.

Even after providing the Auto contacts , there is no solution . please refer (2nd attachment) .
The iterations are going on as I experienced two days back.

Request your assistance for the same.

Many thanks & regards,

Jagadish Megadi
Assistant Manager – Design
Tenova Delkor India

[Andrew.Sartorelli]

Hi Jagadish,

General contact is not the equivalent of bonded contact, it is the equivalent of separation contact in the newer version of Nastran In-CAD.In Nastran In-CAD 2015 bonded contact may in fact be called welded contact, in which case that would be the appropriate one to use for your model.

Regards,
Andrew

[Andrew.Sartorelli]

Hi Jagadish,

Were you able to run the model with the settings I provided?

Regards
Andrew

[Anonymous]

Hi Andrew ,

We were able to run the analysis . Thank you so much for your regular feedbacks.
However I still feel Nastran in CAD 2015 is very very slow when it comes to big models with more than 50 parts.

Please suggest how to go about large assembly files.

Many thanks & Regards,

Jagadish Megadi

[Andrew.Sartorelli]

Hi Jagadish,

Newer version of the software, Nastran In-CAD 2016 SAP and Nastran In-CAD 2017 have had some improvements made to make working and post-processing models much easier. You will need to update Inventor from 2014 to same version year of Nastran In-CAD that you want to work with however. This is because we've added a lot of improvements to the software, and some of those improvements are dependent on components of Inventor. Because these components could behave differently in future or previous version, we decided to ensure a satisfactory experience by requiring a version of the software the we know will function as expected.

Regards,

Andrew