General Contact- Abaqus Standard

[Kushagra2892]

Hello All,
I am simulating contact between a fabric (consisting of membrane elements) and a stick (consisting of Analytic rigid body) using Abaqus/Standard. The overall assembly detail I have attached below:

The stick falls over the fabric and rotates to twist the cloth. Here is the image showing the overall aim of the simulation :

Now I will come directly to my query. The fabric consists of membrane elements,so I have basically double sided surface. For Fabric and Stick interaction, I am using surface to surface contact and for interactions within the Fabric, I am trying General contact. I have tried 3 cases with General Contact definition and result for all the 3 cases is same. I cannot understand why is it so? It would be really helpful is someone can explain why it is happening.

Aforementioned 3 General Contact cases are :

1st case : All* with self.
2nd case : Selected surface pairs.

Surfaces 5 and 6 are the two surfaces of the Fabric respectively

3rd case: Selected surface pairs.

[tt]I have the understanding that all 3 cases are different because in the 2nd and 3rd case, I am choosing specific surface pairs while in 1st case I am choosing all surface pairs. Why the results are still same?[/tt]

Thank you all in advance.

 

[FEA way]

By default general contact domain includes all exterior element faces apart from those belonging only to cohesive elements. It also accounts for self-contact. Contact inclusions are used in some (rather rare) cases to speed up the analysis by specifying only selected regions that are expected to experience contact during the analysis.

 

[Kushagra2892]

Thanks a lot for your input. I did not know this. I thought it will only deal with the included surface pairs.

So to select individual surface pairs , I need to go with surface to surface contact? But I am not sure if its possible to select two different sides of same surface in Surface to surface contact.

 

[FEA way]

You can use contact inclusions if the analysis solves faster. But in this case, I think that the default setting of the general contact should work fine.