When we twist a bar inside a slot bar had contact on slot walls. Problem is bar is penetrating inside the wall. How to avoid. Contacts were made in Hypermesh, analysis done in ansys apdl.
Hi,
you will have interpenetration depending on your contact algorithm and real constants. The penalty (KEYOPT(2)=1) and augmented Lagrangian (KEYOPT(2)=2) contact algorithms use contact "springs" to establish a relationship between the two contact surfaces. The spring stiffness is called the contact stiffness. An increase in stiffness results in a decrease in penetration, but often increases the computational cost.
Zero penetration is enforced by using Lagrange multiplier contact algorithms (KEYOPT(2)=3 or 4). This method adds contact traction to the model as additional degrees of freedom and requires additional iterations to stabilize contact conditions.
Multi point contraints (MPC) might be an option to connect different parts in your model without using contact elements (which is a science of its own).
See Sect. 3.9. "Set the Real Constants and Element KEYOPTS" in the Contact Technology Guide in the ANSYS Mechanical APDL Documentation.
Regards
Hi,
The real constant, FKN will drive the penetration levels of surface to surface contact.
Please keep it as default value and do not try to change the same. Still, if you find more penetration which is not allowable,( normally 1mil could be acceptable for a metal surface to surface contact problems). Increasing of FKN value will reduce the contact penetration values.
Hope this Helps,
Regards
Sowmi
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