Development Of A Detailed FE Skull Model And Research On Injury In Vehicle Traffic Accidents

With the development of the society, there are more vehicles on the road, and morevehicular accidents as a result. In China, the economic and spiritual damage was suffered bythe people because of the accidents injury. In all accidents, more than30%is head injury.The accidents can lead to a variety of injuries, such as skull fracture and contusion. Finiteelement method is a powerful tool and can simulate the process of crashing. In this way, thedistribution of force and stress in the head can be analyzed in any time point during collision.However, the accuracy of simulation is limited by the bio fidelity of the FE model. Most ofresearches were concentrated on the brain injury, and the skull model was very simple,especially facebone. As the situation above, a detailed FE skull model was built to study theskull injury.In this paper, the finite element (FE) model was constructed based on the CT data from50th adult volunteer. The CT data was exported in Mimics and the structure of skull wasrepaired to keep the model accurate. Then the model was smoothed and built the surface inGeomagic Studio. The surface model was converted into solid and the skull meshes wereestablished in Hypermesh. The skin and brain were built based on the meshes of skull. In thispaper, the model included the skull, facebone, sinuses, skin, brain and soft tissue on the face.The total model was made up of367183hex elements,16711shell elements,192884nodesand the mass was about4.414kg. The materials of the model were referred from publishedliteratures.In order to make sure that the model was accurate enough to analyze the crash andinjury, various cadaver tests were chosen to simulate to validate the model, including testsconducted by Yoganandan, Nyquist and Allsop. The fracture of skull or facebone wasobserved in those experiments, and the fracture was also researched in simulation. Thecontact force, deformation and break-deletion elements were calculated by LS-DYNA. Thefracture in simulation was similar with that in cadaver tests and the results showed that the model was able to predict the injury and fracture of the skull.At last, a comparison model without sinuses was built and used to simulate the Allsop’scadaver tests. By comparing the results of those simulations, the effect of the sinuses to thedynamic response of the skull was studied. The result showed that if the sinus is not far awayfrom the impact location, it would have an effect on the response of the skull, such as thedeformation, fracture and the distribution of the stress and strain in the brain. Otherwise, itseffect on the overall response of head could be ignored.