A New Approach to Contacts and Rigid Body Inter- actions in LS-DYNA
Traditionally in LS-DYNA (almost) all contact definitions use a penalty formulation. This means that penetration in the contact is required to obtain a contact force between interacting entities. It is then up to the user to verify that the penetrations are small enough not to influence the results. The Mortar contacts [1], which have become the preferred choice for implicit analyses, is of penalty type. Also, the rigid walls (*RIGIDWALL) use a penalty method in implicit analyses. To find a good penalty stiffness setting may be problematic if solid elements (especially tetrahedra), or soft materials, such as rubber or plastic, are involved. It can be hard to find a good trade-off between reasonably small penetrations and implicit convergence.
https://www.dynalook.com/conferences/14th-european-ls-dyna-conference-2023/simulation-methods/jonsson_dynamore_nordic.pdf/view
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A New Approach to Contacts and Rigid Body Inter- actions in LS-DYNA
Traditionally in LS-DYNA (almost) all contact definitions use a penalty formulation. This means that penetration in the contact is required to obtain a contact force between interacting entities. It is then up to the user to verify that the penetrations are small enough not to influence the results. The Mortar contacts [1], which have become the preferred choice for implicit analyses, is of penalty type. Also, the rigid walls (*RIGIDWALL) use a penalty method in implicit analyses. To find a good penalty stiffness setting may be problematic if solid elements (especially tetrahedra), or soft materials, such as rubber or plastic, are involved. It can be hard to find a good trade-off between reasonably small penetrations and implicit convergence.
Jonsson_DYNAmore_Nordic.pdf
— 2.0 MB