ABSTRACT
One of the most intriguing aspects of ammonium perchlorate (AP) decomposition is its incomplete decomposition at low temperatures, in which the decomposition halts at a level of approximately 30%. Various theories have been proposed to explain this observation based on physical and chemical arguments. Here we consider the notion that geometry itself might contribute to this limiting value. Percolation theory involves the “connectedness” of a geometric lattice, and a network is said to percolate if it is connected continuously end-to-end. It has been demonstrated that in a cubic lattice, percolation occurs at a site density of ~31.1%, remarkably similar to the limiting void fraction in AP. A Monte Carlo (MC) algorithm using simple rules has been developed and applied to particle decomposition. The MC simulations result in porosity evolutions that are reminiscent of actual AP behavior in terms of the overall limiting porosity which is developed, the effect of particle size, and the sigmoidal time response.
Acknowledgments
Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. Department of Energy or the United States Government. This project was supported financially by the Joint Munitions Program (JMP) under Technical Coordination Group-III (TCG-III). The helpful reviews by Jeff Kay, Cole Yarrington, and Judith Brown are appreciated.