Numerical and experimental approaches of the interaction BLAST/THORax – BLASTHOR
BLASTHOR or the understanding of the mechanisms of the interaction of the blast wave with the thorax to provide greater protection
While Improvised Explosive Devices on current military conflicts are increasingly used, the survivability of the soldier related to the penetrating trauma is significantly increased due to the improvement of the ballistic protective suit. However, blasted survivors show some classical patterns such as lung injuries, but also Traumatic Brain Injuries and Post Traumatic Stress Disorders. One of the expected key body zone in the triggering mechanisms would be the thorax.
Focus on the thoracic area of the human body, mainly exposed to blast.
-To improve understanding of primary blast-related injury mechanisms on lungs<br />-To revisit numerical approach by taking into account this atypical threat in order to get an efficient numerical tool.<br />-To think and design future surrogates improving personal protective equipment testing.<br />
The study begins with an experimental and numerical cartography of the pressure around a charge detonating in free-field condition. Secondly, instrumented targets with simple geometries are designed to assess blast loading and physical responses of the materials. Next, comparison will be made between these targets and more sophisticated targets such as a hybrid III dummy and also compare with available data from literature on biological models to get a representative injury risk criteria. Finally, we will propose an efficient numerical tool with some recommendations to improve surrogates for blast testing and personal protective solutions.
A state of the art was drawn up to serve as basis for our investigations.
Some scenarios of exposure have been selected. One of the major concerns is the placement of the target compared to the path of the triple point defining the upper extremity of the Mach stem. This sets the conditions of threat depending on the pressure time history. The cartography of these pressures has been done and the numerical part is currently in progress.
In the future, the development of a dedicated mannequin and numerical tools should contribute to open new insights for improving current personal protective equipments and the prediction of the risk incurred as a function of the subjected traumatic event.
The findings concerning the cartography of the pressure around the charge will be presented to the 23rd International Symposium on Military Aspects of Blast and Shock (MABS 23) which is held at Pembroke College in Oxford, UK from 7-12 September 2014.
Recent clinical observations due to: military forces engaged through current conflicts (demining, improvised explosive devices,…), industrial explosions (AZF,…), or linked with urban terrorist bombings, emphasize the risk for the personal to be injured by blast waves.
This study is designed to bring new insight on the understanding of the blast-induced injury mechanisms and finally, provide some ways of improvement of the personal protective equipment which can be worn. The different tasks scheduled in this study will need to be the substrate of long terms works.
After doing a state of the art, this study will focus on the understanding of the physiological effects of blast waves on human being. It will need to improve the currently used anthropomorphic devices by combining both biological and biomechanical experimentations with numerical simulations.
Project coordination
Pascal MAGNAN (Institut franco-allemand de recherche de Saint Louis) – pascal.magnan@isl.eu
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
Partner
UNISTRA Université de Strabourg
ISL Institut franco-allemand de recherche de Saint Louis
Help of the ANR 263,333 euros
Beginning and duration of the scientific project:
December 2012
- 36 Months
