Find connectivity

Hi,

In did a connectivity check on my model and found some parts that are not connected, even though a contact is modeled that should connect this part to the other parts. How can that happen?

(I attach my model file )

Thanks!

Unable to find an attachment - read this blog

Find more posts tagged with

English

Radioss

Accepted answers

All comments

Altair Forum User

Hi,

Please check the springs in the model. Since they were not properly defined the connection was not established.

I deleted all the spring elements and just created three and you can see that now connectivity has been established between L1 and L2 solid components. Please check the attached file. Always recommend you to run the model checker (Tools>Model Checker) once the model is set up so that it will show the modeling errors and the user can rectify it.

Unable to find an attachment - read this blog

Altair Forum User

Hi George!

Cool!! Thanks a lot for your help!

Just two question to understand it: L2-solid is also connected by the contact L2. Shouldn't L2 then show connectivity due to that contact even the spring elements are not connected? and 2nd: What was the reason that spring elements were not connected? I created it by 1D>springs>option: spring2 and selected the nodes. Is something wrong with that?

Thanks, Regards

Jonas

Altair Forum User

And maybe 1 futher question: Why does it create a '^faces'-component at the contact_L1 elements when I test connectivity?

Altair Forum User

Hi Jonas,

By defining contacts the solver will check for any penetrations between the master and slave and it will not show connectivity between parts. The steps mentioned for creating spring is correct, but I think you may not have properly selected the nodes for defining the spring.

Altair Forum User

So it only shows connectivity when there are penetrations? Sounds wired.

Altair Forum User

Hi,

No.I was just telling how contact works. That is, once the master slave sets are identified by the solver, the algorithm will check these locations for potential penetration of a slave node through a master segment, and this check is done in every time step. This is how contacts works. It will not create connectivity between parts.

Regarding the '^faces'-component, can you please tell which option you have used to check the connectivity?.

Altair Forum User

Ah ok! I understand it now!

I did it this way: userprofile: Radioss => tools>find connectivity>right click 'Find connectivity'> Select all components > check.

Altair Forum User

Hi,

I just tried with the same option and in my case no ^faces collector was created.

This collector will be created only when user use Faces panel which is used to find the free faces in a group of elements. In that case all of the elements created during a find are placed into a component called ^faces which is created by the find faces command.

Altair Forum User

Ah sorry, i just realize it does not happen when i check connectivity but when I use the model checker (Model Checker>Radioss Block). Since I always did both I thought it comes from connectivity check.