Impact Injury Analysis Of Thorax And Abdomen Based On Finite Element Model Of A 3-year-old Pediatric Occupant

With the rapid development of automobile industry,automobile has become one of the most important modes of transportation for people to travel daily.However,the car brings us convenience and convenience,but also brings great security risks.According to the statistics of traffic accidents,nearly 20,000 children under the age of 14 die in traffic accidents every year in our country,among which,four to eight years old children have severe chest and abdomen injuries.Therefore,it is of great significance to study the mechanism of the injury of children’s chest and abdomen to improve the safety of automobile and reduce the risk of injury to the chest and abdomen of children.Cadaver experiment is an effective way to study the mechanism of thoracic abdominal injury,but its application is limited.The rapid development of finite element simulation makes it an important way to study the damage mechanism of children’s chest and abdomen.In this paper,the finite element model of the three-year-old and six-year-old children is derived from the same research group,and validated by comparing the cadaver experiment.By reconstructing the child cadaver experiment of the Euclidean,the impact of impact hammer size,material parameters and geometric parameters on the thoracic lesion was compared from the amount of chest compression,the contact force,and the maximum first principal strain of the chest heart and lungs.It was found that that influence of the geometrical parameter on the damage of the children’s chest was the most obvious,and the material parameters and the impact of the impact weight had a slightly influence on the children’s chest injury.The two groups of children of different ages were restrained by the use of the validated 3-year-olds and 6-year-old child occupant finite element model,with reference to the pulley experiment in ECE R44 regulation,and the difference between the severity and position of the chest and abdomen injury during the frontal impact in the three-and six-year children were compared.In the pulley test,the severity and position of the thoracic and abdominal injuries of children aged 3 and 6 were significantly different.In addition,the severity and location difference of the occupant’s chest and abdominal injuries were compared and analyzed by comparison and analysis of the three years old children under different initial speed conditions.The results showed that the speed parameters showed differences in the severity and location of the chest and abdomen injuries in the simulation test for the 3-year-old children.The degree of damage to the chest and abdomen was not only increased with the increase of the initial velocity,but also the comprehensive analysis of various indexes of the chest and abdomen injury.The finite element model of the upper extremity of the three-year-old children was constructed,and the upper limb finite element model was connected with the model of children’s chest and abdomen.With reference to the E-NCAP experimental setup,3 years old occupant model in a normal ride and upper limb raised two positions were set in car rear seats,,and constrained by the five point child safety seats in the process of rigid column side collision,to analysis the influence of the upper limbs to the chest injury.Results show that upper limbs in the process of side crash to absorb part of the collision energy,to avoid the car parts and safety seat,direct contact with occupant of the chest of occupant chest rose to a certain degree of protection.