Shadowgraphy Provides a useful qualitative look at the propagation of the blast wave Allows transparent phenomena i.e. pressure waves, to be made visible due to refracted light Images captured on high-speed camera. Objective:
To determine materials best suited for blast wave mitigation within the confines of a helmet.
Blast Wave Mitigation
Professor Steven Son,
Matthew Alley, Stephen Strinka
Brain injuries due to blast waves have contributed an increasing portion of casualties in Iraq and Afghanistan. Current body armor was designed for protection against shrapnel, but is ill-equipped to prevent blast waves
from damaging the brain. The purpose of this experiment is to
determine suitable materials for disrupting blast waves within
the constraints of a helmet. Candidate materials were chosen
based on weight, microstructure, and proven capability to
inhibit blast waves. The materials were cast into
dimensionally uniform samples and subjected to blast
waves. Pressures near the explosion and behind
the samples were recorded. In addition, high
speed shadowgraphy provided a qualitative
look at the propagation of the blast wave.
An analysis of this data will reveal the
best choice in material for blast wave
mitigation. The results are still
forthcoming, as the experiments
are currently underway. Once a
material is selected, it will be
suggested for use within
School of Mechanical Engineering
-Used to direct explosive blast wave toward material
Pencil Gages monitor pressure
-10.5” from explosion
-20” from explosion, behind material
-20” from explosion, exposed
The material is placed in test fixture
-10.5” from explosive
-pressure at this distance calculated to be 50 psi
-a blast pressure of 50 psi can be lethal
Observed Blast Waves
The characteristic idea blast wave (Fig 11) is composed of 2 parts:
-A sharp peak pressure, caused by the mass of propagating medium
-A brief vacuum follows the peak, air refills the void left by the wave
-Experimental Data (Fig 12) matches basic pattern
- but interference creates a
 S. Okie, "Traumatic Brain Injury in the War Zone," The New England Journal of Medicine, vol. 352, pp. 2043-2047, 2005.
 D. Warden, "Military TBI During the Iraq and Afghanistan Wars," The Journal of Head Trauma Rehabilitation, vol. 21, pp. 398-402, 2006.
 C. Wilson, "Improvised Explosive Devices (IEDs) in Iraq and Afghanistan: Effects and Countermeasures," CRS, Ed. Washington, DC: The Library of Congress, 2007.
 Y. Bhattacharjee, "Shell Shock Revisited: Solving the Puzzle of Blast Trauma," in Science. vol. 319 Washington, DC: AAAS, 2008, pp. 406-408.
 C. Stewart, "Blast Injuries," CO: USAF Academy Hospital, 2006.
The SURF program is supported by alumni and the following corporations and organizations:
A special thank you is extended to Intel for their continued support of the SURF program, including providing materials for professional development activities.