Human modeling for injury assessment during ejection

Abstract

Safety has always been a paramount issue to address in cockpit design and equipping. Current methods used in safety validation are predominantly empirical and performed using elaborated rocket sled apparatus on human surrogates. These tests are both time and cost intensive. In light of these constraints, computational modeling has presented itself as an efficient means to streamline the evaluation of ejection safety. An integrated computational analysis, leveraging on Multi-Bodies Solid Dynamics (MBSD), Finite Element (FE) and Computational Fluid Dynamics (CFD) techniques, has been employed to study injury phenomena during ejection. In the MBSD modeling, a computational model, simulating a pilot subjected to Vertical Accelerator (VA) test, was created and verified. Concurrently, a CFD model, using potential flow assumptions, was developed to predict the effects of windblast. The two models will be integrated to allow interactive considerations of both fluid and impulsive forces during ejection. Finally, the forces ascertained from the simulations will serve as the loading conditions for the FE model of the human cervical spine, created to predict the propensity and assess the mechanism of neck injuries. The integrated tool will add to the available arsenal used to evaluate the safety implications of new systems incorporated into the cockpit.