Contact forces are output in the rcforc file. This tabular result
can be used for 2D postprocessing. Contact forces between certain parts of a
surface-to-surface or single-surface contact can be extracted by using force transducers
(*CONTACT_FORCE_TRANSDUCER_PENALTY_ID). For Mortar contacts, the force
transducers must be defined based on parts or part sets.
You can save the output of contact gaps and contact pressure for 3D visualization in the intfor file. Then, complete the following steps:
On card 1 of the contact definition, set the parameters SPR and MPR to 1.
The keywords
*DATABASE_BINARY_INTFOR_FILE(available from R10.2) and*DATABASE_EXTENT_INTFORare required to specify the file name, output frequency and content of the 3D interface force file. These parameters are already defined in the include files database_cards_static.key and database_cards_dynamic.key.For analyses in R10.1 or prior, use the include file database_cards_before_R102.key. You must then add
s=intforon the command line for submitting the LS-DYNA analysis.
Constraint-based tied contacts do not store contact pressures in the interface force file (intfor), while penalty-based tied contacts do.
Mortar contacts output contact diagnostics in the message file (messag or mes00*):
A report of initial penetrations during initialization.
At the beginning of each implicit time step, a report of the number of segments in contact, the maximum penetration (absolute and relative) and warnings if there are nodes that are close to being released by the contact.
This can be very useful information for debugging convergence problems related to contacts. From R12 of LS-DYNA, penetration information is also saved to the d3plot and intfor files for fringe plotting, and to the sleout file (binout format only) for curve (history) plotting.