Learning Forum

[las1234]

Hello everyone ,

i want to simualte tyo different part with difeerent pressure but i don'T GET IT .. like yoiu can see it in the photos below

Thank you

[peteroznewman]

Please use the Windows Snipping Tool to capture images from the screen to paste into your posts. Also, clean your monitor!
Under Analysis Settings, turn on Auto TIme Stepping. Set the Initial and Minimum Substeps to 10, and Maximum Substeps to 100. Change Large Deflection to On. When you solve, you might get a better result.

[las1234]

thank you for your answerSir .
i can't run it i have this message this message
Max.Geometric gap 3.32869534 has been detected between contact
element 56948 and target element 60918.
WARNING: The geometric gap/penetration may be too large.Increase
pinball radius if it is a true geometric gap/penetration.Decrease
pinball if it is a false one.
can you please clarify this ? Thank you

[peteroznewman]

Under the Connections folder there is one Bonded Contact and two Contacts. What are theses for? If you didn't create them, delete them. If deleting the unnecessary contacts fixes the problem, great.
If you need these contacts, what type are they? Show the contact side and the target side of the contact pair.
There is a line in the Contact Details called Pinball radius. That is what you either need to make bigger is smaller, depending on what you are trying to do with the contact.

[las1234]

hello , yes i need the contact between the membrane and the ring . i made the membrane and the walls a single part to make the simulation easier . i thougnt it's will not seperate from the membrane but it did . should i do contact for the walls and the membrane too ?
Thank you very much Sir

[peteroznewman]

Open the Geometry in SpaceClaim, go to the Workbench tab and click the Share button.
Don't use any Contact.

[las1234]

hello Sir ,
Thank you .
i have another question . i have a maximum Stress of 18 MPA . how can i know the Permissible Strain ?
Thanks

[peteroznewman]

When you say you have a maximum stress of 18 MPa, do you mean the material allowable stress is 18 MPa or do you mean the stress result had a maximum value of 18 MPa?
It you mean allowable stress, then for a linear material, the allowable strain would be allowable stress / Young's modulus.
But for a nonlinear material, the allowable strain would be a material property that the manufacturer would provide. For metals and rubbers, that is often called the Elongation at Break or just Elongation.

[las1234]

i mean the Stress result had a maximum value of 18 Mpa .
should i compare this maximum Value with the tensile Strength or yith something else ? Thank you Sir im little bit confused

[peteroznewman]

Stress is a tensor, so in 3D, there are six components of stress. In a thin fabric, that has no bending stiffness, there are only three stress components in the plane of the fabric, two normal directions and a shear stress. Those can be converted to a Maximum Principal stress which you could compare with the Tensile Strength.

[las1234]

Hello Sir , Thank you a lot .

i have another question please . I want to put pressure on the top and I want the bottom to stay fixed so I can see the deformation of the inner walls and the top. Here is the photo you can understand what I mean.
Thank you @peteroznewman

[peteroznewman]

You can set the bottom face to Fixed Support. That is like gluing it to the table. This will have a better chance of converging than the next suggestion.
It would be more involved to add a table surface and use contact between the table and the bottom.

[las1234]

i hope you are well.
I have another question please. I want to simulate the same thing with a different material but it won't simulate I just changed the emodulus and poisson number.
Thank you

[peteroznewman]

What was the error?

[las1234]

Thesolverenginewasunabletoconvergeonasolutionforthenonlinearproblemasconstrained
The unconverged solution (identified as Substep 999999) is output for analysis debug purposes. Results at this time should not be used for any other purpose.
Thank you

[peteroznewman]

Please read some of the links in this Google Search of this site that describe many ways to address this problem.
https://www.google.com/search?q=site%3Aforum.ansys.com+%22unable+to+converge%22