In LS-DYNA, many different element types and element techniques are available. This section presents a brief overview of elements that may be used in implicit analyses, see Table 4. Depending on the application, other element types or modeling techniques may be a better fit. There are several special beam, shell, and solid element formulations for linear analyses, see Table 5.
An additional functionality of *CONTROL_IMPLICIT_EIGENVALUE is to specify element types for implicit analyses. This makes it possible to switch element formulations very quickly in, for example a crash model to element formulations better suited for implicit analysis. Note that section properties for beams are not converted when beam element formulation is switched. A template for switching to shell element formulation 20 and solid formulation 18 follows:
*CONTROL_IMPLICIT_EIGENVALUE Data line for eigenfrequency calculation 18,,20