Monochromatic Laser-Induced Shockwave Measurements with Improved Data Processing for Reactive Materials
Abstract
We present enhanced measurement and data-processing techniques for a modified laser-induced air shock from energetic materials (LASEM) system. This system was recently upgraded with a 640-nm imaging laser and monochromatic high-speed camera, which, when combined, allows for higher frame-rate imaging and the ability to penetrate through the optically thick plasma at early times (<10 s). We implement an automated shockwave detection code via MATLAB that improves the throughput of data analysis speed by over 10. We present the efficacy of various models and empirical fits using the higher frame-rate data. The characteristic shock velocity is analyzed across various time intercepts and beam energies and optimal settings are discussed. Only small changes in the characteristic velocity are observed over a roughly approximately 150-mJ laser energy range near the standard operating value. A suite of powdered metal samples has been analyzed using the upgraded system, which demonstrates the ability for the system to differentiate performance across an array of materials. Results from the new system correlate well to previous iterations. The upgrades allow for the rapid assessment tool for the microsecond energy release of reactive materials, particularly for samples with subtle performance differences (e.g., metal particles with varying sizes).
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2021
- Accession Number
- AD1134858
Entities
People
- Elliot R Wainwright
- Jennifer L Gottfried
Organizations
- United States Army Research Laboratory