Mathematical model for temperature fields at initial stage of fire

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Fire hazard of bromination processes of n-nitro-t~-methoxystyrene during modelling of different technological disruptons (change of temperature regime of the process, volley pouring of reacting substances, turning off and subsequent turning-on of rabble etc.) has been studied. Low intensity gaseous combustion, when it is induced by external ignition source, has been found out. The conditions of process regimes, where phlegmatization of gaseous phase over reaction mass takes place, have been determined. Ways for subsequent optimizaion of the process were determined during study. Possibility and expedience of use of sulfuric acid, that is waste product in production of hydrogen chloride is examined. This will allow to decrease the amount of acid waste and to increase safety of the process. Obtained results will allow to begin studY of safety bromination in large-scale experiments using pilot installation and to develop recommendations for provision of safety bromination in industry. FIRE SAFETY OF BUILDINGS, STRUCTURES AND PREMISES Fire Prevention Measures for Subway Rolling Stock by Means of Self-Acting Powder Extinguishers M. N. Vaisman, A. V. Dolgovidov, V. V. Pivovarov All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia V. V. Popov Higher Engineering Fire Service Technical School

Statistics of fire occurrences at subway rolling stock and tactical characteristics and specifications of self-acting powder extinguisher (OSP) have been analyzed. Using of self-acting powder extinguishers for fire prevention at subway rolling stock is offered. The results of full-scale fire tests of these extinguishers at the time of stop and movement of train are represented. Based on the test results the self-acting powder extinguishers are recognized suitable for improvement of fire safety of subway rolling stock. Software for Determination of Hazardous Parameters in Accidents with Fires and Explosions at External Installations with Combustible Gases and Liquids Yu. N. Shebeko, V. L. Malkin, L M. Smolin, V. A. Kolosov, E. V. Smirnoo, A. S. Parshin All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia

For risk evaluation and safety promotion for external installation with combustible gases and liquids the determination of hazardous parameters for accidents with fires and explosions are required. The following processes have been included in the software: vapor cloud dynamics during liquefied gas discharge through a pipe and during liquid pool evaporation, vapor cloud explosion after liquid pool evaporation or gas ejection, radiation intensity from pool fires and fireballs, BLEVE, liquid overflow through the dyke during instantaneous liquid storage destruction. The main features of the software 'FM' and the possibilities of its application for the risk assessment and safety promotion have been described. Mathematical Model for Temperature Fields at Initial Stage of Fire l. S. Molchadsky All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia and I. F. Astakhova Voronezh State University

Method of mathematical modelling for temperature fields in conditions of initial phase of fire is studied. The mathematical model is formulated as conjugate problem and is

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specified as in Cartesian, as in cylindrical coordinates. The results of numerical tests are compared with the results of physical tests. The conclusion about the range of practical use of the mathematical model with reference to fire resistance problems of building constrictions is made. FIRE ENGINEERING Development of Unified Air-foam Extinguisher V. V. Pivovarov, G. N. Vasiliev, V. V. Peshkov, S. M. Stepanov All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia The information about development of unified air-foam extinguishers OVP-5 and OVP-10 is stated. The scheme of the extinguisher is presented. Their advantages in comparison with foam chemical extinguishers are considered. Tactical characteristics and specifications are represented, The main characteristics of extinguishers and their design features are analyzed. FIRE EXTINGUISHING Determination of Length and Depth of Penetration and High-temperature Zones of Turbulent Gas-solid Aerosol Jet from Generator for Volume Extinguishment V. M. Nikolaev, A. F. Zhevlakov, N. B. Arbuzov All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia The engineering method for calculation of parameters (length and depth of penetration, high-temperature zones) of gas-aerosol jets flowing out of generators used in enclosure fire-extinguishing installations is proposed. To determine these parameters only the turbulent jets constant is applied without use of any other constants equalizing experiment and calculation results. Installation for Determination of Extingmshing Aerosol Concentration V. V. Maslennikov, L. G. Nevodnichenko, B. P. Druzhinets, A. V. Kapranov, B. L Gorshkov, B. A. Zuikov, A. P. Arbuzov All-Russian Research Institute for Fire Protection, Ministry of the Interior, Russia The automatic measuring system for optical diagnostics of concentration fields and rates in two-phase flows, where concentration of aerosol is from 10 to 1(~a g/m 3 and rate is less than 100m/s is described. The system is based on computer 'Elektronika BK-0010-01'. The concentration is measured by means of the attenuation method with use of 20 optical transducers (a couple of receiver-emitter). The rate is measured by means of 'flight-time dependent' method, using transducers with time resolution of 1.5 ms. Taring of transducers is made using model two-phase flow with controlling characteristics. The error of measured concentration is 5 %. The system is intended for diagnostics of large-scale two-phase flows and, in particular, for studying of aerosol fire extinguishing means.