Plenary Lecture

The Fluid Mechanics of the Response of Confined Explosives to Hypervelocity Impact

Dr. John Curtis
UCL Honorary Senior Research Fellow
Royal Society Industry Fellow
QinetiQ Fellow
Room 21, Building Q27
Fort Halstead
Sevenoaks
Kent TN14 7BP
UK
E-mail: jpcurtis@qinetiq.com
 

Abstract: When an explosive is struck by a particle travelling at very high speeds of the order of several km / s a powerful shock is transmitted into the explosive. As the violence of the impact increases the reaction of the explosive also becomes more violent. Reactions can range from inert, to minor burning, to deflagration, to the so-called deflagration to detonation transition, and finally to outright detonation. The last two of these can, of course, have catastrophic consequences if there is further volatile material in proximity. Many efforts to model the relationship between the impact parameters and the resulting reaction have therefore been attempted. A brief review of these is provided and then the methods in current use at QinetiQ are reviewed. The fluid mechanics of these methods is discussed and it is shown how a new method based upon shock physics has been applied to create a simple but effective empirical model for the impact of cylinders. Some remaining unsolved problems are reviewed.


Brief Biography of the Speaker:
Following his first degree in mathematics at Corpus Christi College, Cambridge, Dr Curtis took an MSc in Theoretical Mechanics at the University Of East Anglia, Norwich, and continued there to complete his PhD on Optimisation in Continuum Mechanics. He had a spell as a spacecraft engineer at British Aerospace, working on the Ulysses and Hubble Space Telescope missions, before joining Scicon to undertake mathematical modelling research on shaped charges. In 1996 he joined QinetiQ, where he has continued his work in this field, publishing papers on all aspects of shaped charge jet mechanics. He was appointed a QinetiQ Fellow in 1996 and is also a Fellow of both the UK Institute of Mathematics and its Applications and of the Institute of Physics. Recently he has been awarded a Royal Society Industry Fellowship and has been appointed Honorary Senior Research Fellow in the Mathematics Department at UCL, working in collaboration with Professor Frank Smith FRS.