The application of numerical techniques to the study of the phenomena that occur during the first milliseconds after the activation of the airbag until recently has remained out of reach, due to the high complexity of the problem. On the one hand, the highly dynamic evolution of the gas produced by the inflator invalidates the hypothesis of uniform pressure within the volume. On the other hand, the simulation of the airbag opening involves problems such as the creation of extremely complex meshes representing the folded bag inside its housing, characterization of the behaviour of strain rate dependent materials, breaking of seam lines, etc.

During the last years several simulation packages have introduced modules to reproduce the gas flow inside the airbag, but experimental methods most commonly used to validate simulations involving airbags are not able to deal with the high speed and lack of accessibility that characterize this stage of the airbag deployment.

The objective of the present studies is the determination of the capability of these simulation tools to be used in the design of parts with attention to the loads produced during the opening of the airbag. This will help us not only to improve the development and integration of components, but, in later steps, also to provide airbag models able to be applied with guarantee in the simulation of OOP. In order to do this, a combined methodology using simulation and instrumentation has been defined, based on the development of numerical models using the FEM software PAM-CRASH and its module for simulation of fluids based on the algorithm FPM. These models have been validated with experimental tests specifically designed for this task. This paper intends to introduce the characteristics of the different stages of the airbag deployment and shows some of the results of the mentioned studies.