Validations of Virtual Animal Model for Investigation of Shock/Blast Wave TBI

Complementary to animal testing and analysis of clinical data, a validated anatomy and physiology based mathematical models can provide capabilities for a better understanding of blast wave brain injury mechanisms, animal-human injury scaling, assessing and improving protective armor. We developed the 3D “virtual” animal models for multi-scale computational simulations of blast induced injury. A multi-scale modeling tool, CoBi, has been adopted for the analysis of blast wave primary TBI mechanisms and coupled biomechanics events. The shock wave over a rat in a shock tube was modeled by the CFD method. The primary biomechanics FEM study uses anatomic based animal geometry with a high resolution brain model. The virtual rat model has been validated against recently collected data from shock tube tests on rodents, including pressure time history in the free-stream and inside the rat brain. The model has been used to conduct parametric simulations to study the effect of animal placement location in the shock tube, and different loading orientations on the rat response. We also compared the rat brain biomechanical response between simulations of a free-to-move and a protected or constrained rat under the same shock tube loading to identify the role of body protection and head movement and on the rat TBI. The implications of these results suggest that virtual animal model could be used to predict the biomechanical response in the blast TBI event, and help design the protection against the blast TBI.