hypervelocity impact lab at jhu...kirana and shimadzu hpv-x2 • flash x-ray imaging –two channel...
TRANSCRIPT
Planned Diagnostics
• Ultra High Speed Imaging - Up to 10 Mfps video with
Kirana and Shimadzu HPV-X2
• Flash X-Ray Imaging – Two channel 300 kV system,
orthogonal soft x-ray tubes
• UV-VIS and Infrared Spectroscopy
• Photon Doppler Velocimetry (PDV) for surface
velocimetry
• Hyperspectral Snapshot Camera (via CASSI) and 3D
Particle Tracking system in development by JHU
collaborators
Hypervelocity Impact Lab at JHUG. Simpson1*, M. Shaeffer1, D. Mallick1,2, K.T. Ramesh1
1. Hopkins Extreme Materials Institute, The Johns Hopkins University, Baltimore, Maryland 21218
2. U.S. Army Research Laboratory, Aberdeen, Maryland 21005
OverviewHEMI researchers are interested in material behavior under a broad range of dynamic conditions. To improve our fundamental understanding of these problems, HEMI has built a hypervelocity impact facility at JHU including a two-
stage light gas gun and enclosed projectile range. The system is designed to accommodate a range of target/ impactor configurations and diagnostics, with flexibility to add capabilities in the future. The facility is expected to be
operational by the end of the calendar year.
Problems of Interest• Fragmentation of Impactors/Targets
• Protective Materials and Structures
• Planetary Impact of Geological Materials
• Impact of Space Debris and Micro-meteoroids
• Multiphase mechanics of high energy impacts
Gun System DescriptionThe hypervelocity impact lab hosts a two stage light
gas gun with a launch tube diameter of 7.62 mm. The
system utilizes a compressed gas breech (as opposed
to smokeless powder) in order to minimize handling
risk, decrease fouling and increase shot-to-shot
consistency. The facility is equipped for hydrogen use,
allowing a maximum launch velocity of approximately
7 km/s. Both smoothbore and rifled barrels will be
available for use.
Gun and Target Tank
Acknowledgements
HEMI thanks Dr. Kevin McNesby of ARL, Dave Strange of PAI,
Don Grosch of SwRI, and the members of the Hypervelocity
Impact Symposium and the Aeroballistics Range Association for
their help and feedback.
Source: PAI
Initial Research
After installation, the hypervelocity facility will be used
initially for DoD funded work involving the fragmentation
of impactors. Experiments to capture and observe the
failure of an impacting body as well as the resulting
fragment cloud will be performed with the goal of
characterizing the mechanisms controlling the dynamic
fragmentation of projectiles and colliding bodies.
Velocity Performance
All combinations of launch mass and velocity below
this curve are accessible. Accelerated mass includes
projectile and sabot.
Accelerated reservoir increases
pressure, rupture disk failure
launches projectile
Drift tube section with multiple ports for imaging
projectile free flight and measuring projectile velocity
Target chamber 3 ft diameter by 3 ft long to
accommodate various targets. Internal rails
provided for mounting
Orthogonal configuration for
flash X-ray heads
Blast tank for gas expansion and
sabot separation
7.62 mm diameter launch tube, can be
smooth or rifled to aid in sabot separation
30 mm diameter pump tube –
H2 or He fill gas
Breech – 10,000 PSI He or N2
to drive pump tube piston
5 rectangular viewports along shot
line, 3 circular viewports looking at
target plane, dedicated pass
through for in-chamber sensors
* Email: [email protected]
𝑉𝑝𝑟𝑜𝑗
Flash X-Ray
Ultra High
Speed Imaging
Flash X-Ray