Modeling And Simulation Of Airbag Based On Corpuscular Method

Airbag is a buffer device between the passenger and the automobile interior. When a carimpact occurs, the airbag can prevent the second impact between the passenger and the carinterior because of the inertia, it’s the last barrier of protecting the passenger to avoid fataldamage. At present, Control-Volume Method and Arbitrary Lagrangian-Eulerian Methodare primary airbag simulation methods. However, the reliability of Control-Volume Methodis not so good in Out-of-Position simulations. The requirements of the hardware and theengineer’s technical level are relatively high for Arbitrary Lagrangian-Eulerian Method.Corpuscular Method is a new method which has advantages of Low technical requirementsand high calculation speed, it has good results in Out-of-Position cases, so this method hasa good future.With the support of Shanghai Hengstar technology Co., Ltd. and another automotiveinterior manufacturer, this paper analyzed the airbag with Corpuscular Method. At the sametime, this paper introduced the working principle of airbag and the species of airbag and thepresent situation of simulation after summarizing the active safety technology and passivesafety technology.This paper introduced the kinetic molecular theory and deduced the expressions ofmacro pressure, temperature and internal energy. This paper deduced the expression ofmolecules’ velocity distribution law, Maxwell-Boltzmann velocity distribution. This paperalso introduced the contact principle of particle-particle contact and particle-fabric contactin LS-DYNA, and introduced the simulation principle of Corpuscular Method inLS-DYNA.This paper established the finite element model of the Out-of-Position conditions inthe Pendulum Test, and carried on the simulation of airbag respectively with theControl-Volume Method and Corpuscular Method in LS-DYNA. After the comparison of the airbag deployments and the barycenter’s acceleration with the test result, this paperverified the reliability of Corpuscular Method.Taking passenger airbag as example, this paper simulated the deployment of airbag.According to the airbag data provided by the factory, this paper established the finite modelof the airbag and obtained the inflator’s the mass flow rate as well as the temperature flowrate based on Tank Test. This paper folded and assembled the airbag model in LS-PrePost.After the preliminary simulation, this paper simulated the process of the airbag getting outof the instrument panel with U-Shaped and H-Shaped weakening line. This paper providesa reference for the airbag design.This paper will provides a reference for airbag design and optimization, and this paperwill help engineers a lot in Out-of-Position cases. It has a great significance for thedesignation and development of airbag in domestic.