Modeling and Research for Human Response to Blast Effects
Challenge
What conditions cause traumatic brain injury from air blast exposure? Are shoulder-fired-weapons training causing serious unintended effects on trainees? Where should explosive breachers stand to reduce injury risk from their own explosives in complex or indoor environments? The U.S. military has had a limited understanding of issues related to the human effects of blast exposure on and off the battlefield, but ARA has conducted research to provide more insight on the issue.
Solution
ARA uses a range of tools from engineering tools to full 3D computational fluid dynamics simulations projects investigating the effects of blast exposure.
In one investigation, DARPA blast gauges recorded overpressure data from combat environments providing a quantitative link between blast exposure and medical outcomes. ARA used blast gauge data to reconstruct the full 3D blast exposure on each subject. By calculating the blast exposure variations across an individual, more meaningful correlations with injuries can be established.
ARA has also created computational models to simulate blast exposure on operators of shoulder-fired weapons using the SHAMRC high-fidelity multi-physics code. The model was validated with experimental pressure data from a number of training events. The simulations provide blast exposure levels over the entire body.
Significant advances in reconstructing IED attacks and other blast events using point data from blast sensors such as the DARPA blast gauge can be used to create more meaningful correlations for short-term and long-term injury patterns.
ARA has also provided explosive breacher modeling, creating computational models to simulate blast exposure on explosive breachers in complex environments using the SHAMRC high-fidelity multi-physics code. The models were validated with experimental pressure data from breaching events. The simulations provide blast exposure levels over the entire body.
The blast exposure information from simulations can be used to create new standoff and shielding guidelines for use by explosive breachers in the field and can also be used to study medical outcomes from blast exposure.
Additionally, pressure and temperature time histories associated with explosive detonations are of particular interest to the military, but measurements are difficult because of short timescales and massive turbulence generated by the gas flows. To overcome some of these difficulties, micron-sized temperature sensing particles were designed by Washington State University and ARA modeled these sensors in a dynamic blast environment using the two-phase particulate flow models within the SHAMRC high-fidelity multi-physics code to simulate sensor motion, heating, and thermal response after a detonation.
