Which Surface Should I Select as the Master in a Contact Pair?

Question

Successful structural analysis involving multiple bodies requires accurate contact definition, this means selecting appropriate master and slave surfaces for each contact. How can I be sure that I am making the best choice?

Solution

There are a few key points to remember when selecting the surfaces that make up a contact pair. They are as follows,

• The slave surface should have the finer mesh grid spacing
• The slave surface should ideally fit within the master surface outline
• The slave surface should have the more complex curvature. For physical contacts the expected curvature (deformation) should also be considered, meaning that the surface belonging to the softer material should be the slave as its deformation will be greater.