Residual Stress as a Boundary Cond.

Altair Forum User

Hello!

 

This should be my last Topic for the next time in which I need advice /emoticons/default_smile.png' alt=':)' srcset='/emoticons/smile@2x.png 2x' width='20' height='20'>

 

Let´s say at example there is a cylinder stress strained in the area of placticity. But the Force stops wide before it reached the tensile strength. After that the cylinder has a residual stress with a different profile and magnitude of tangential- , radial-  and axialstress. How can I type in that status of stressprofile (magnitude included) as a boundary condition for next analysis? 

At example to have a look to the superpoition with the new stress. Or to see the magnitude of the force which breaks the cylinder with the stresses in it.

In my simulation I used an implicit analysis HyperWorks v 12, Hyper Mesh, Radioss Block 110 format.

 

 

Altair Forum User

Hi Fabian,

 

Please refer to  RADIOSS FAQs>> Initial stresses

<?xml version="1.0" encoding="UTF-8"?>

Altair Forum User

Dear Mr. Pagadala,

 

thanks for your advice. It helped a lot. I now have the right files (.sty) in which my results are in Ascii format available. But it´s not obvious for me how to bind in the files.

i normally had the starter and engine file.

I started the analysis with the radioss solver run manager, typed in the path to the starter file (with options - both for engine).

I know I have to use the /inista card. But I have no idea how to continue.

 

Greetings

Altair Forum User

Hi,

 

You should see a file with the extenstion .sta.

 

Please import that file in HyperMesh with the below options checked.

 

Now, apply the material and loads and carry the simulation. The .sta file will have the stress, strain data along with the thickness variations.

<?xml version="1.0" encoding="UTF-8"?>

Altair Forum User

Hey!

 

I actually had no .sta file. Only the sty -files. But I now created a -sta file with /state/dt ....

Okay, there are written the bricks with nodes and coordinates.

But it´s not possible to use the .sty? There are still written every Stresses and strains.

 

It´s a bit confusing to me, why I create everything in HyperMesh, start the analysis, get a .sta file. And then make the whole process with the .sta file?

 

Greetings

 

Edit:

 

In Radioss FAQ:

'It is possible to define an initial stress state by using option /INISTA.

This option uses an OUTPUT file (Runname_0000.sty) describing the structure of the model for which a file Runname_nnnn.sty defines a stress state.'

 

Now at this point there should be written, how bind both files in the analysis!

Altair Forum User

Fabian,

 

Please use .sta instead of .sty.

Altair Forum User

I´m afraid, it did not work

Altair Forum User

Hi Fabian,

 

can you please share your model files?

Altair Forum User

Thanks for sharing the files.

 

I will get back to you asap.

Altair Forum User

Thank you for your help

Altair Forum User

Hi Fabian,

 

Is the material used for the second simulation is same as the first?

 

could you please share the .out file and also the starter and engine file for the simulation 2?

Altair Forum User

Hello Mr. Pagadala, 

 

yes, the material is the same. I uploaded it in your Dropbox.

Altair Forum User

Thanks for sharing the files.

 

I will check and update to you soon.

Altair Forum User

Thanks for helping!