About XII Symposium on Combustion and Explosion
September 11 - 15, 2000,
XII Russian Symposium on Combustion and Explosion was held at Druzhba holiday home on September 11-15 2000. The event was organized by the Scientific Council on Combustion and Explosion at the Presidium of the Russian Academy of Sciences, the Institute for Problems of Chemical Physics, the Institute of Structural Macrokinetics and Materials Science and the Institute for Problems of Mechanics.
250 experts from different Russian institutions as well as foreign researchers took part in the Symposium. The Scientific Program included 31 oral and 300 poster presentations.
The Symposium was opened by Academician A.G.Merzhanov, the Chairman of the Council. He gave some general comments for the Symposium Program and told about activity of the Scientific Council. The participants stood in the memory of one of the main organizers of previous Symposia Corresponding Member of the RAS F.I.Dubovitskii who passed away after XI Symposium.
The Chairman of the Organizing Committee Corresponding Member of the RAS G.B.Manelis presented an introductory lecture entitled "12 Symposia on Combustion and Explosion". He told about the history of the Symposia and emphasized the role of this event in developing combustion and explosion direction in the Soviet Union and Russia. The lecture was prepared in collaboration with Prof. V.V.Barzykin. Research workers from ISMAN actively participated in the Symposium. They gave 5 oral and 39 poser presentations.
The Corresponding Member of the RAS V.V.Azatyan delivered a lecture entitled "Effective Inhibitors for Preventing Inflammation, Explosion and Detonation of Fuel Gas Mixtures" that presented some data obtained upon studying inhibitors of new types. The main idea used during the search for new efficient inhibitors was as follows: branching-chain mechanism of reactions is defining factor for fuel gases combustion not only at pressures hundreds times less than the atmosphere pressure but at the atmosphere and much higher pressures. The theory for inhibition processes of gases combustion and explosion was developed. Some compounds with p-bond (olefines and their derivatives) were found to be inhibitors cleaving reaction chains very effectively. Due to the presence of p-bond an inhibitor molecule easily captures active intermediate particles thus cleaving reaction chain. The high efficiency of the studied inhibitors for preventing inflammation, explosion and detonation as well as for controlling intensity of burning and destroy of previously formed detonation wave was illustrated.
The lecture "Combustion of Elemental and Thermite Systems in Microgravity" presented by Prof. V.I.Yukhvid in collaboration with V.N.Sanina, A.G.Merzhanov, A.S.Rogachev, A.E.Sytschev and V.A.Shcherbakov was devoted to two approaches to study of SHS under microgravity conditions. The first approach realized at terrestrial conditions includes two stages: (i) experimental study of effect of compressing ("positive") and stretching ("negative") overloads on SHS processes and (ii) interpolation of SHS parameters from "positives" and "negatives" zones to the point of zero gravity. The second approach was realized aboard the MIR Space Station under long-lasting microgravity conditions (10-2 g). Comparison of the data obtained under terrestrial and microgravity conditions demonstrated that:
1. Macro- and microstructure of space and terrestrial combustion products markedly differ while their chemical and phase composition are almost identical;
2. The combustion rate and sample elongation for burning in space correlate with data obtained by using interpolation approach;
3. Microgravity drastically affects on structure formation in completely molten products of combustion in highly caloric systems.
The participants of the Symposium were significantly impressed with the lecture "Mathematical Modeling of 3D Spinning Waves for Gasless Combustion" delivered by T.P.Ivleva and A.G.Merzhanov. The lecture presented some principal data on the mechanism of 3D spinning waves propagation in the area of instability obtained by computer simulation. A wide range of types for a hot spot motion in the burning sample was analyzed. The lecture was perfectly illustrated by using multimedia presentation with animation.
Prof. V.S.Trofimov gave the lecture entitled "Combination of the Zel'dovich and Michelson Theories as Applied to Inhomogeneous Condensed Systems". In this presentation, a supposition about widening the detonation front in SHS systems is given. As was shown, the widened front at steady-state detonation could occur only for quasi-steady detonation wave. The theory of turbulent detonation can be applied for description of the averaged structure of such a wave. This theory applies equations of averaged quasi-steady motion having a form of equations for steady laminar flow of the reacting medium. In the case of initiation of the medium reaction on the front border of the quasi-steady wave the task about selection rule for detonation rate has to be solved anew. However under some assumption of a common character, the phase point lies above the equilibrium detonation adiabatic line of the medium resulting in combination of these two theories takes place.
In the lecture "Some Points in the Modern Study of SHS Processes", Prof. I.P.Borovinskaya told about new approaches in the field of SHS connected with controlling composition, structure and characteristics of the combustion products. Some examples for solution "fine" tasks (synthesis of silicon nitride powders with high content of aphase and aluminum nitride powders with controllable particle size and in the form of single-crystal whiskers and fibers. Some results on developing nitride ceramic materials with desired structure determining physico-chemical and mechanical properties of parts are presented. Methods for controlling porosity and density of materials (including application of volume shrinkage of the sample upon combustion and volume effect of nitration) are discussed. A number of new results on determining the mechanism of structure formation for hard-alloy functionally graded materials during combustion and subsequent thermal treatment was presented.
The lecture "Electro-thermal Explosion as a Method for Fast High-Temperature Reactions of Combustion in Condensed Media" by A.S.Shteinberg and K.V.Popov was dealt with analysis of the present state-of-art in the theory and practice of electro-thermal explosion (ETE). The ETE mode was shown to be the most suitable for quantitative kinetic experiments, because self-heating of significantly long sample at high power of electrical heating occurs in spatial-isothermic way. This allows a simple equation of heat balance of unsteady character with lumped parameters to be applied for calculations.
The participants of the Symposium demonstrated marked interest to discussions organized in the evenings.
The Symposium demonstrated intense interest of Russian experts and researchers to the area of combustion and explosion processes.