Research On Structural Design And Appliance Of Vehicle Front Rail Crashworthiness

Vehicle passive safety is one of the key problems for the automobile industry.How to improve the crashworthiness of vehicles has been the key issue of the automotive safety. The thin-walled metallic components---the most conventional and effective energy-absorbtion device, have been widely used in the automotive design and manufacture. The thin front rail is the main deformation and energy-absorbption structure in frontal crash. The crash energy of the car was absorpted by the plastic deformation of thin-walled front rail and the acceleration of the car was determined by the average compressive load of the vehicle front collision energy absorbing structure,while the thin-walled structure has played a leading role in the compression deformation of the car. The performance of the vehicle crashworthiness is determined by the deformation and the energy-absorption of the front rail. Therefore,the structural design of vehicle front rail crashworthiness in the frontal crash has a great engineering significance.This paper starts with summarizing the condition of study crashworthiness of vehicle with domestic and overseas. Then this paper analyse the several important factors which affect the crash simulation results,such as:the grid cell size, timestep setting,strain-rate effects, contact friction coefficient and material Stamping; The paper discusses the distortion wavelength and the energy absorption characteristic of square thin-walled straight beam structures' crashworthiness, which was affected by the following factors:impact speed (exterior load),axes length material intensity,material thickness,section size and so on. On the basis of the above work, the paper studies the collapse mode and energy absorption characteristic of simple frontal crash rail; Using the production of the above work, the paper makes some improvements on the frontal crash rail. In further research, the paper discusses the mechanism of occupants' injury and improves on key components, such as the frontal crash rail, based on the frontal impact design principles. The result shows that it cut down the peak acceleration of the car effectively and controll the intrusion of pedal group and fire wall.The result manifestes that the design and methods in the paper are appropriate and effective, so the research has a important significance impact on the engineering field.