Bulletin of the American Physical Society
20th Biennial Conference of the APS Topical Group on Shock Compression of Condensed Matter
Volume 62, Number 9
Sunday–Friday, July 9–14, 2017; St. Louis, Missouri
Session K2: Energetic and Reactive Materials: Detonators and Initiators |
Hide Abstracts |
Chair: William Neal, AWE Room: Grand Ballroom AB |
Tuesday, July 11, 2017 2:15PM - 2:30PM |
K2.00001: The Response and Mechanism of Response of PETN Chip Slapper Detonators to Electrical, Thermal and Mechanical Threats Elizabeth Lee The successful design of electro-explosive devices requires their safety characteristics as well as performance to be considered. In order to design components that pass the necessary safety tests an understanding is required of the way in which the various threats interact with the device and in particular the explosive fill(s). A prototype PETN chip slapper detonator has been subjected to a suite of electrical, thermal and mechanical threats. Insulted detonators have subsequently been examined using X-ray CT to assess the damage to the explosive fill. Using fundamental understanding of the initiation of PETN compacts and chip design an attempt has been made to understand the conditions at which reaction occurs, the parameters which may dictate the violence of such a reaction and the mechanism by which reaction occurs in order to design detonators which contain the necessary mitigating features. A comparison to a semi-analytical model has been made. British Crown Owned Copyright 2017/AWE. [Preview Abstract] |
Tuesday, July 11, 2017 2:30PM - 2:45PM |
K2.00002: A Statistical Representation of Pyrotechnic Igniter Output Shuyue Guo, Marcia Cooper The output of simplified pyrotechnic igniters for research investigations is statistically characterized by monitoring the post-ignition external flow field with Schlieren imaging. Unique to this work is a detailed quantification of all measurable manufacturing parameters (e.g., bridgewire length, charge cavity dimensions, powder bed density) and associated shock-motion variability in the tested igniters. To demonstrate experimental precision of the recorded Schlieren images and developed image processing methodologies, commercial exploding bridgewires using wires of different parameters were tested. Finally, a statistically-significant population of manufactured igniters were tested within the Schlieren arrangement resulting in a characterization of the nominal output. Comparisons between the variances measured throughout the manufacturing processes and the calculated output variance provide insight into the critical device phenomena that dominate performance. [Preview Abstract] |
Tuesday, July 11, 2017 2:45PM - 3:00PM |
K2.00003: Numerical Simulation of Energy Conversion Mechanism in Electric Explosion Wang Wanjun, Lv Junjun, Zhu Mingshui, Fu Qiubo Electric explosion happens when micron-scale metal films such as copper film is stimulated by short-time current pulse, while generating high temperature and high pressure plasma. The expansion process of the plasma plays an important role in the study of the generation of shock waves and the study of the EOS of matter under high pressure. In this paper, the electric explosion process is divided into two stages: the energy deposition stage and the quasi-isentropic expansion stage, and a dynamic EOS of plasma considering the energy replenishment is established. On this basis, flyer driven by plasma is studied numerically, the pressure and the internal energy of plasma in the energy deposition stage and the quasi - isentropic expansion stage are obtained by comparing the velocity history of the flyer with the experimental results. An energy conversion model is established, and the energy conversion efficiency of each process is obtained, and the influence of impedance matching relationship between flyer and metal plasma on the energy conversion efficiency is proposed in this paper. [Preview Abstract] |
Tuesday, July 11, 2017 3:00PM - 3:15PM |
K2.00004: Computational Prediction of Shock Ignition Thresholds and Ignition Probability of Polymer-Bonded Explosives Yaochi Wei, Seokpum Kim, Yasuyuki Horie, Min Zhou A computational approach is developed to predict the probabilistic ignition thresholds of polymer-bonded explosives (PBXs). The simulations explicitly account for microstructure, constituent properties, and interfacial responses and capture processes responsible for the development of hotspots and damage. The specific damage mechanisms considered include viscoelasticity, viscoplasticity, fracture, post-fracture contact, frictional heating, and heat conduction. The probabilistic analysis uses sets of statistically similar microstructure samples to mimic relevant experiments for statistical variations of material behavior due to inherent material heterogeneities. The ignition thresholds and corresponding ignition probability maps are predicted for PBX 9404 and PBX 9501 for the impact loading regime of U$_{p}$ = 200 – 1200 m/s. James and Walker-Wasley relations are utilized to establish explicit analytical expressions for the ignition probability as a function of load intensities. The predicted results are in good agreement with available experimental measurements. The capability to computationally predict the macroscopic response out of material microstructures and basic constituent properties lends itself to the design of new materials and the analysis of existing materials. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700