The effect of head mass on its biomechanical response during lateral impact to the head is investigated in this computational study. The mass of the head of a state-of-the-art validated finite element head model is altered by ± 10 % from the base value of 4.7 kg. Numerical simulations of lateral head impacts for 30 cases (representing 15 human cadaver experiments × 2 mass configurations) are performed using the LS-DYNA solver at different velocities ranging from 2.4 to 6.5 m/s and three impacting conditions representing different stiffness and shapes of the contact/impact surfaces. Results are compared with the original model using the baseline head mass, thus resulting in a total of 45 simulations. Present findings show that the head mass has greater influence for peak interaction forces and the force has a greater dependency on stiffness of contact surface than the shape. Mass variations have also influence on skull strain energy. Regardless of increase/decrease in skull strain energy influenced by head mass variations used in the computational study, the 50 % fracture tolerance limit was unaltered, which was 544 mJ. The present study gives a better understanding of the mechanism of temporo-parietal skull impact.
Keywords: Finite element model; Parametric study; Peak forces; Skull fracture; Temporo-parietal impact experiments.