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Regarding the contact settings for interference fits in Optistruct

I currently have two parts with an interference fit of 0.55mm. When modeling the actual model, it was through penetration, and the mesh division was also through penetration. I set Clearance=-0.55 in the optistruct contact, but the mesh nodes remained through. Is this correct? Or do we need to manually move the grid nodes to not penetrate, and then set Clearance=-0.55? Which of these two modeling approaches is correct?

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Accepted answers

Rajashri_Saha

Yes, the grids need to be penetrated from beginning. You can see the example file I shared.

All comments

Jin1

And my working condition is a plug-in condition, an interference fit insertion condition, so I turned on continuous sliding and activated it in contparm as well

Rajashri_Saha

Hi,

If you are doing interference fit, let the components be in penetrated stage (the actual outer component should be penetrated inside inner component with required distance which in your case 0.55mm). As stated by you give clearance= -.55 in PCONT card.

Refer the attached example for a detailed explanation.

Interference_fit.fem

Thanks

Rajashri

Jin1

Did I understand correctly? Are you saying that the grid also penetrates 0.55mm, and the PCONT card is also set to -0.55? If my working condition is to insert one part into another (continuous sliding), is that also the case?

Rajashri_Saha

Yes, the grids need to be penetrated from beginning. You can see the example file I shared.

Jin1

No, I tested the case you uploaded. As long as Clearance is set, the spatial position of the nodes is not important. Even if the grids do not overlap, as long as the clearance distance is negative, the two boards will be pushed apart. Additionally, I checked the help documentation and found another sentence: Using overrides the default contact behavior of calculating initial gap opening from the actual distance between Secondary and Main.