Advanced Airbagsimulation using Fluid-Structure-Interaction and the Eulerian Method in LS-DYNA

Many accidents with children or small adults, where the ignition of the airbag leads to dangerous and even fatal injuries for the passengers, have led to a number of efforts to analyze this so-called „Out-ofPosition“ load cases more deeply within the development process of an airbag system. In the framework of simulation systems the fluid-structure interaction between the inflating gas and the airbag fabric has not been taken into account in the past. Recent developments in the LS-DYNA software package allow a fully coupled arbitrary Lagrange-Euler formulation and thus a more exact representation of the airbag deployment process within the simulation system. In the present contribution we will describe the standard procedure, based on the assumption of a uniform pressure distribution in the airbag and the recently achieved advances in LS-DYNA with respect to fluidstructure interaction of the expanding gas and the inflating airbag fabric.