Computer simulations are widely used in modern automotive industry to design effective restraint systems, such as airbags. Until recently, the uniform pressure method (UPM), which assumes uniform pressure distributions inside the airbag, is mostly used in the design of airbags. The uniform pressure method is appropriate with fully inflated airbags interacting with in-position or belted occupants. However, with recent safety regulations for protecting occupants of various sizes and seating positions as well as the implementation of side airbags, Out-of-Positions (OOP) simulations are becoming more and more important for airbag suppliers and the OEMs. To simulate OOP cases, gas flow approaches are implemented in various commercial finite element codes in different forms.
This paper discusses the recent developments in the Coupled Eulerian-Lagrangian (CEL) method for airbag deployment simulations available in Abaqus/Explicit. A passenger airbag model was selected for the evaluation of accuracy of the CEL method. This paper also discusses some advanced Coupled Eulerian-Lagrangian method features available in Abaqus/Explicit in order to facilitate efficient occupant safety simulations.