My introduction to the fascinating phenomena associated with detonation waves came through appointments as an external fellow at the Department of Physics, University College of Wales, and at the Department of Mechanical Engineering, University of Leeds. Very special thanks for his accurate guidance through the large body of information on gaseous detonations are due to Professor D. H. Edwards of University College of Wales. Indeed, the onerous task of concisely enumerating the key features of unidimensional theories of detonations was undertaken by him, and Chapter 2 is based on his initial draft. When the text strays to the use of we, it is a deserved acknow ledgement of his contribution. Again, I should like to thank Professor D. Bradley of Leeds University for his enthusiastic encouragement of my efforts at developing a model of the composition limits of detonability through a relationship between run-up distance and composition of the mixture. The text has been prepared in the context of these fellowships, and I am grateful to the Central Electricity Generating Board for its permission to accept these appointments.

This document contains twenty-four selected papers presented at the International Colloquium on Advanced Experimentation & Computation of Detonations, September 14-17 1998, St. Petersburg, Russia. The papers discuss recent advances made in understanding detonation wave initiation, propagation, mitigation and control through experimental and computational studies. The book contains five Parts: Detonation Initiation, Detonation Wave Structure and Propagation, Detonation Mitigation and Control, Applications of Detonation Phenomena, and Detonability of Advanced Fuels. The volume is intended to be a tool to explore the international state of the art and an avenue for further follow-up for the researchers and practicing engineers.

Of late the demands of industry in creating new composite and functional materials with present properties stimulated an increased interest to the investigation of processes which occur in the detonation technologies of complex chemical composition with an additive of disperse particles. The collection includes a series of papers presented at the 3d International Conference "Lavrentyev Readings on Mathematics, Mechanics, and Physics" (Novosibirsk, 1990),was held by the Hydrodynamics Institute under the support of the Presidium of the Siberian Branch of the USSR Academy of Sciences to stimulate the international cooperation of the leading international centers. In the framework of this Conference the Round Table seminar was held by Prof. A. Borissov and Prof. V. Mi trofanov devoted to "Dynamic Structure of Detonation in Gaseous and Dispersed Media". The idea to hold such Round Table was supported by Chairman of Organizing Committee academician Prof. V.Titov from Hydrodynamics Institute, and academician Prof. V. Nakoryakov and also his Institute of Thermophysics. The main ideas discussed at the Round Table were presented in the form of papers which reflected present situation of the problem of dynamic structure of the detonation waves in gaseous and dispersed media. The basic experimental facts concerning of complicated mul ti dimensional non-stationary structure both of the detonation wave and its front surface, generation of the cell structure, the effect of transverse waves, obstacles, channel geometry etc. on the transition from dynamic regime to stationary structure are represented in the fist three papers.

Theoretical analysis shows that a detonation wave in a gaseous explosive bounded by an inert gaseous medium propagates at a lower velocity than it would have if the explosive were inside a tube with a solid wall. The velocity decrement is found to be dependent primarily on the ratio of the initial densities of the explosive and the inert gases, the reaction length of the explosive and the extent of the explosive normal to the interface. An extension of composition limit criteria shows that there is a limit to the velocity decrement beyond which the detonation is expected to quench and therefore deteriorate into a shock. Extensive experimental results on H2-O2 mixtures bounded by nitrogen and some results on stoichiometric CH4-O2 bounded by different gases show a general agreement with theory. (Author).