Экспериментальная оценка объёмной концентрации и размеров твёрдых частиц дыма, образующихся при терморазложении горючих материалов

Abstract

Purpose. The purpose of the work is the experimental assessment of size as well as mass and calculated volumetric concentration of smoke solid particles formed during burning of combustible materials, using wood, insulation of cables and microelectronics elements as the examples. Methods. The authors used the experimental method for measuring the amount, size and mass of suspended solids particles in a gaseous medium formed in a small-scale experimental installation during the combustion of various substances and materials. Findings. The enhancement of experimental installation has been carried out and the experimental methodology has been developed that allows measuring the parameters of solid smoke particles. Experimental dependencies on the time of mass and countable volumetric concentration of smoke particles depending on their size have been obtained during testing wood samples, insulating cables and microelectronics elements. It has been found that the most dangerous, in terms of the effect on a human body during evacuation in case of a fire, finely dispersed solid particles of smoke are formed throughout the entire burning time. It is shown that the maximum mass and countable volume concentration of particles is formed at the incipient stage of combustion, and the mass volume concentrations of particles of all sizes significantly exceed their critical values. Research application field. The results can be applied at determining the blocking time of escape routes by visibility loss, and the consequences of human body exposure to smoke particles. Conclusions. It is necessary to conduct further studies in order to justify the introduction of a new fire hazard into regulatory documents on fire safety – the concentration and size of smoke particles, as well as create a database on the size of smoke particles formed during combustion of modern combustible substances and materials, and their mass and calculated volumetric concentrations.