Injury Protection Efficiency Of Side Airbag For Elderly Passengers

With the development of automobile industry and the increase of car ownership in China,there are a lot of traffic accidents each year.Human beings are threatened by serious traffic accidents that is the largest public hazards in the world.In many forms of traffic accidents,the mortality rate of side impact accidents is particularly high.The side of cars is the weakest part for protection,injury and death rate of passengers is very high in side impact accidents.Relative to the physical characteristics of adults,elderly people are more likely got injured in side impact accidents.Therefore,it is significant to research injury mechanism of elderly people in side impact accidents.The study of side impact protection efficiency for the elderly passengers are relatively rare at home and abroad.On the one hand,the shortage of the research results in data deficiencies;On the other hand,due to ethical reasons,it is also impossible to study what damage the elderly passengers will get through the traditional body experiment.On the basis of a large number of literature research,this paper obtains a set of reliable rib parameters data for elderly passengers finite element model,and then puts it in the full vehicle model and models a side airbag.Using computer simulation technology for side impact simulation analysis,protection efficiency of side airbag for the elderly passengers is studied.First of all,side impact finite element model is established according to the C-NCAP standard.Using the Hypermesh software to set up elderly passengers model,moving deformable barrier and full vehicle model,and then LS-DYNA software is used as a solver.Secondly,referencing the NHTSA real vehicle collision result,the simulation model is compared to ensure the simulation model can accurately simulate side impact in real life.Thirdly,using the LS-PREPOST software for post-processing,the acceleration curve and stress curve of the finite element model are got.This paper mainly studies the acceleration curve of the head,chest and abdomen for the elderly passengers.Finally,three most affected factors in the side airbag are selected by range analysis of orthogonal test design.Using Box-Behnken of the response surface method to make simulation analysis of the side airbag,and construct the second order regression agent model to optimize the airbag,to reduce the injury risk of the elderly passengers.The results of this paper show that different parameter settings of the side airbag will directly affect the elderly passengers injury degree.Improper settings of the airbag parameters can lead to serious head,chest and abdominal injury.Through the optimization of the side airbag parameters,the airbag vent diameter of 60 mm,airbag volume of about 10.2 L,and detonating time of 15 ms is optimal.The original peak acceleration of head,chest and abdomen has respectively fallen by 40.62%,48.02%and 29.98%.In addition,side impact comprehensive damage evaluation value WIC is 0.785,down by 16.7%compared to the original 0.943.Improved effect is very obvious.