Higher Time-Resolution LASEM, Part II: Influence of Plasma Chemistry on the Laser-Induced Shock Waves of Explosives
Abstract
The laser-induced shock waves and emission from five different military explosives were measured with an improved laser-induced air shock from energetic materials (LASEM) setup. The new system has a higher time-resolution than the original LASEM configuration and more advanced diagnostic capabilities to track the plasma and combustion chemistry for the excited materials. The materials investigated include trinitrotoluene (TNT), triaminotrinitrobenzene (TATB), cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX), and hexanitrohexaazaisowurtzitane (CL-20). The laser-induced shock velocities strongly correlated to the measured detonation velocities of the explosives, enabling estimation of detonation performance with milligram quantities of material. Fewer laser shots were required to obtain comparable confidence intervals to those obtained with the original LASEM configuration. For the first time, automation of the shock wave position measurements with sufficient accuracy to enable discrimination of energetic materials was demonstrated. Alternative methods for fitting the propagation of the laser-induced shock wave were also investigated. Application of blast-wave models to the LASEM data provided new insights into the effect of the laser-induced plasma generated by energetic materials on the surrounding air and plume expansion. Time-resolved temperatures and near-infrared emission spectra have been reported for the excited explosive samples for the first time, providing insight into the reaction chemistry.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 02, 2020
- Accession Number
- AD1108554
Entities
People
- Brian C. Barnes
- Jennifer L Gottfried
Organizations
- United States Army Research Laboratory