ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

5. DISCUSSION, CONCLUSIONS AND PERSPECTIVES
Three experimental impacts, achieved on cadaver heads, have been reconstructed
numerically in the present study. The fractures that were observed in the experience
were also relatively well predicted by the numerical tools. Nevertheless the prediction is
not as accurate as it could be desired but rather coarse. In terms of interaction force
between the head and the impacting mass, the comparison between the experimental
measurements and the numerical predictions are rather good. Some discrepancies exist
and a high amplitude second impact appears in the numerical simulation. That
numerical second impact has to be explained especially in its comparison to the
experimental one: why is it so dampened in the experience? Why is it so in relief in the
simulation? Eventually, the SUFEHM predicts very well the skull fractures in terms of
global strain energy of the skull. However, efforts have to be made in the accuracy of
the fractures location. More generally, the following perspectives can be explored to
increase the correlation between experience and simulation:
A more detailed meshing of the skull including reinforcement beams and
variable bone thicknesses.
A face with an elastic plastic brittle mechanical behaviour and a more accurate
meshing. Such a face, modelled like the skull, could allow predicting fractures
that extend to an orbita.
A more realistic boundary condition for the head which is left free in the
numerical simulation but embedded in the pendulum in the experiment. This
means to model the complete experimental impact device with respect to the
masses and inertias.
More experimental impacts. This could allow us to have a better understanding
of the phenomenon that occur and especially the second impact which has a very
high amplitude in the numerical simulation compared to the experimental test.
A future use of the SUFEHM as a prediction tool for forensic application in
assault or falls for example.
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ACKNOWLEDGEMENTS This research received funding from the CCUFB-BFHZ Franco-Bavarian Centre for
University Cooperation. The authors want also to acknowledge Professor Jos Van Der Sloten and his team from the
Department of Mechanical Engineering of the Katholieke Universiteit Leuven for the experimental data they provided.