Chapter 1: Introduction to LS-DYNA

LS-DYNA is a general-purpose finite element program capable of simulating complex real world problems. It is used by the automobile, aerospace, construction, military, manufacturing, and bioengineering industries. The LS-DYNA solver is optimized for shared and distributed memory Unix, Linux, and Windows based platforms, and it is fully QA'd by Ansys. The code's origins lie in highly nonlinear, transient dynamic finite element analysis using explicit time integration.

"Nonlinear" means at least one (and sometimes all) of the following complications:

  • Changing boundary conditions (such as contact between parts that changes over time)

  • Large deformations (for example the crumpling of sheet metal parts)

  • Nonlinear materials that do not exhibit idealy elastic behavior (for example thermoplastic polymers)

"Transient dynamic" means analyzing high speed, short duration events where inertial forces are important. Typical uses include:

  • Automotive crash (deformation of chassis, airbag inflation, seatbelt tensioning)

  • Explosions (underwater Naval mine, shaped charges)

  • Manufacturing (sheet metal stamping)

LS-DYNA's potential applications are numerous and can be tailored to many fields. In a given simulation, any of LS-DYNA's many features can be combined to model a wide range of physical events. LS-DYNA is one of the most flexible finite element analysis software packages available.

LS-DYNA consists of a single executable file and at the solver level is entirely command line driven. Therefore all that is required to run LS-DYNA is a command shell, the executable, an input file, and enough free disk space to run the calculation. All input files are in simple ASCII format and thus can be prepared using any text editor. Input files can also be prepared within the Ansys Workbench and Ansys Mechanical environments.

There are many third party software products available for preprocessing LS-DYNA input files but the Ansys Workbench LS-DYNA interface combines the perfect combination of power and ease of use. Licensees of LS-DYNA automatically have access to all of the program's capabilities, from simple linear static mechanical analysis up to advanced thermal and flow solving methods.

The LS-DYNA Workbench system takes the power of the LS-DYNA solver and wraps it up into the familiar and easy to use environment of Ansys Workbench and Ansys Mechanical. This unlocks the power of parameterization, CAD import, meshing and all of the other technology which makes Ansys Mechanical the world's number one engineering simulation tool.