The SMOOTH option for contact uses a surface fitting algorithm so that the contact can be calculated on the surface, rather than on the linear element. All the smooth contacts are available for MPP, only the forming smooth contacts are available for SMP. Using the SMOOTH option, LS-DYNA will automatically fit a smooth surface from the mesh. The SMOOTH option works for implicit as well.
For both the SMP and MPP LS-DYNA version, there are some restrictions concerning this option:
For the SMP LS-DYNA version, there are some further restrictions concerning the SMOOTH option:
Any edge with an angle between two contact segments bigger than an angle defined by FLANGL (*CONTACT optional Card C) will be treated as feature line during surface fitting in smooth contact.