Computational modeling of human head under blast in confined and open spaces: primary blast injury

SUMMARYIn this paper, a computational modeling for biomechanical analysis of primary blast injuries is presented. The responses of the brain in terms of mechanical parameters under different blast spaces including open, semi‐confined, and confined environments are studied. In the study, the effect of direct and indirect blast waves from the neighboring walls in the confined environments will be taken into consideration. A 50th percentile finite element head model is exposed to blast waves of different intensities. In the open space, the head experiences a sudden intracranial pressure (ICP) change, which vanishes in a matter of a few milliseconds. The situation is similar in semi‐confined space, but in the confined space, the reflections from the walls will create a number of subsequent peaks in ICP with a longer duration. The analysis procedure is based on a simultaneous interaction simulation of the deformable head and its components with the blast wave propagations. It is concluded that compared with the open and semi‐confined space settings, the walls in the confined space scenario enhance the risk of primary blast injuries considerably because of indirect blast waves transferring a larger amount of damaging energy to the head. Copyright © 2013 John Wiley & Sons, Ltd. This paper is a computational study of traumatic brain injury (TBI) when a human head model is exposed to blast scenarios in three different spaces: open, semi‐confined, and fully confined. TBI is investigated to address the effects of confinement on primary blast injuries (PBI) in terms of injury‐related biomechanical parameters of acceleration, intracranial pressure, and shear stress. The results show that the reflected blast waves from the walls increase the risk of PBI.