A Simple ALE Sloshing Example

Sloshing problems can be simulated using several techniques in LS-DYNA that range from using a simple MAT_ELASTIC_FLUID modeling to a complex ALE or SPH modeling. In this post, a simple problem is set up to demonstrate the fluid representation using ALE element formulation 11 that uses a null material and an EOS (Gruenesium). The sample…

September 18, 2007 | by

Damping for Airbags

When simulating airbag deployment, using the classical uniform-pressure (CONTROL VOLUME) or non-uniform-pressure (ALE, Particle), users frequently encounter oscillations. These oscillations are generally categorized as local and global. To reduce both forms of oscillations, LS-DYNA provides two types of damping that are briefly discussed here. 1. Mass-Weighted-Damping The parameter MWD in *AIRBAG_{OPTION} keyword provides a means…

November 22, 2006 | by

Airbag Leakage Modeling in LS-DYNA

In the area of numerical simulations involving the use of airbags to absorb impact energy, passively or actively, accurate definitions of airbag leakage parameters play a crucial role in predicting the response of impacting objects (ex. occupants). LSDYNA provides various options for airbag leakage modeling that may appear overwhelming at first but are actually quite…

September 14, 2006 | by