| 1. PrefaceIn our country, the step of car getting into family become faster. Along with the number of possessing vehicles increasing, the safe problem of car is being paid close attention extremely by people. The number of traffic accidents was reduced in last two years in our country, but there were almost 0.1 million people died due to traffic accidents annually. the rates of traffic accidents occurrence and death are more higher than developed country in west, that indicate that the level of safety vehicles in our country is still lower, so it is becoming more important to improve the safety of the vehicle .To arrive at that, two facilities have been introduced. One group of facilities, referred to as active safety facilities, aims to reduce the possibility that a crash occurs. The other group of facilities, referred to as passive safety facilities, which involves the occupant restraint system that comprises safety belts, air bag, instrument panel, seat, steering system, etc. The research is focused on mechanical characteristics of belts and airbag that could achieve optimal restraining performance, avoiding second crash between body and interior.Occupant restraint system can protect passenger effectively in right use, but it can make passenger injury in inaccuracy use. If passenger is out of position, such as he does not use the safety belts or his initial position is more anterior, he is possible to contact with the airbag when it is expanding and be hurt seriously. So the rules of safety for vehicles are enacted in developed country, the request of OOP protection in the rules are strict, and that the research in OOP protection have produced many useful results, some of that have been applied in the vehicle production. Whereas only one load case requirement in our country safety rules, and the OOP protection is not be care in the process of airbag system design, so the research in technology of OOP protection in our country is at a lower level.Along with the improvement of passive safety facilities, the study is develop towards the direction of devising a smart occupant restraint system which can protect passengers in many load case, so the research in OOP protection become very important. Under this background, base on a homemade car and the frontal regulation FMVSS208 regulated by USA, this thesis mainly study on the simulation and test method in OOP research, and discuss the way to optimize the airbag system in OOP case. 2. Scope of Paper1. On the basis of reading a large number of papers and regulations, the internal and external status of passive safety and restraint system had been investigated in this thesis. Airbag system has been introduced by its working principle and its drawbacks. The injury mechanism caused by airbag while passenger out of position is elaborated.2. Compare with USA and Europe safety standards, we see that there are some obvious shortcoming in the safety rule of vehicle front crash in our country, especially in the OOP protection aspect, so the requests about OOP protection in the frontal regulation FMVSS208 are summarized. Through the study of advanced technology about smart occupant restraint system developed country, we know the direction about the occupant restraint system study. A method in OOP protection study is provided on the basis of occupant restraint system study method that we have mastered.3. According to the data of a homemade passenger car, a driver side airbag system CFD simulation model is established, and the method of modeling is discussed, which involve CAD model, CAE model and the dynamic realization. The simulation model has been validated in basal characteristics of airbag system airbag system.4. The airbag static deployment test and dynamic impact test had been designed for airbag model validation, and the CFD simulation model has been validated in kinematics and kinetics characteristics of airbag system. The CFD model and Uniform-Pressure model have been compared. It is obvious that the CFD model more valid than UP model in OOP study through the contrast result analysis. The problem in process of airbag model validation has been discussed.5. On the basis of requests in FMVSS208 about OOP static test, the driver side 5th Percentile Female Hybrid III out of position case has been studied. In the study, base on detailed request in rule, two different form OOP static tests have been set, and the simulation models have been established according to the data of a homemade passenger car. The validation and stabilization of simulation models have been validated roundly. Based on the Abbreviated Injury Scale, the analysis of injury has been made, and a conclusion was be testified that the injury of the driver who is in OOP status is mainly come from neck and chest compared with the driver who is not in OOP status. At last, the restraint system of the car has been optimized, that based on the advanced technology about airbag system. 3. Significance of Paper1. This paper explored and mastered the method of simulation and test about OOP protection study, and accumulated some valuable modeling method and experience. This paper also described the process of establishing a CFD airbag model and OOP static test model. Through a lot of work, we finally got a validated, stable simulation model, which was the base of future simulation work.2.The research of testing the data analysis while correcting in model herein, have very important meanings in the correcting of artificial model, through the accumulation in scientific research, have summarized some laws of test data analysis, can be regarded as the reference of relevant research next.3. This paper has realistic meanings to research the smart occupant restraint system of our country, reference that can be developed as the smart occupant restraint system.
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