A particle image velocimeter for measuring the output of high energy detonators

Conference · Fri Jan 01 04:00:00 EST 2010

OSTI ID:992165

Murphy, Michael J ^[1]; Adrian, Ronald J ^[1]; Clarke, Steven A ^[1]

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1. Los Alamos National Laboratory

Results from feasibility experiments are presented to confirm that tracer-particle motion resulting from mass-velocity fields created by driving high-energy detonator output into dynamic witness plates can be successfully measured using particle image velocimetry (PIV). Experimental results, application challenges, and PIV system development are presented. In shock mechanics research, the ability to quantitatively measure the state of compression of shocked materials in two and three dimensions based on particle tracer methods is of extreme importance since such measurements provide precise temporal snapshots of two and three-dimensional shock-induced velocity fields. This is especially true in the science of detonation physics where such measurements provide enormous insight into fundamental. questions for understanding shock-loading processes, effects of shock-front curvature, and mechanisms of energy conversion from stimulus to shock output. As an example, answering such questions is paramount to the understanding and development of newer, safer detonators. To date, few attempts have been made to develop and implement standard particle tracer techniques to measure shock-induced flows resulting from explosive devices. The experimental challenge lies in developing a methodology wherein a tracer particle's inertia does not hinder its ability to accurately move with the rapidly changing flow field. We have recently developed the ability to characterize the output of unloaded explosive initiators (e.g. exploding bridge wires, exploding foils, laser-driven plasmas, etc.) using an optically-based diagnostic consisting of an ultra-high speed, time-resolved PIV system and inert, transparent polymers serving as dynamic witness plates. Initiator output is directed into a witness plate, and measurements of shock and mass velocities are made in a two-dimensional plane aligned with the initiator centerline. The results allow initiator output to be quantified in any in-plane direction, typically along the centerline. The successful development and implementation of the new diagnostic to unloaded initiators provides the groundwork for characterizing full-up detonators employing high explosives (HE).

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: DOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 992165
• Report Number(s): LA-UR-10-01463; LA-UR-10-1463
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
47 OTHER INSTRUMENTATION
CHEMICAL EXPLOSIVES
COMPRESSION
DETONATORS
DIMENSIONS
ENERGY CONVERSION
EXPLOSIONS
EXPLOSIVES
IMPLEMENTATION
PHYSICS
PLATES
POLYMERS
TRACER TECHNIQUES
VELOCIMETERS
VELOCITY