POLIVANOV O. Increasing the efficiency of fire extinguishing due to the discrete supply of extinguishing substances

The dissertation is devoted to the solution of an important scientific and practical task in the field of fire safety, namely: increasing the efficiency of extinguishing class A fires in multi-story buildings by reducing the time of free fire development due to the discrete supply of extinguishing agents to the fire source. The introduction provides a general description of the dissertation work. The relevance of the dissertation topic is substantiated, the purpose of the work and the main tasks of the research are formulated, the connection of the work with scientific programs is shown. The data on the personal contribution of the acquirer, approval of the work and publications are given. In the first section, ANALYSIS OF TECHNICAL MEANS AND METHODS OF FIRE EXTINGUISHING THAT ENSURE THE DELIVERY OF FIRE-EXTINGUISHING SUBSTANCES, an analytical review of the state of fires for the period from 2018 to 2022 in Ukraine is provided. The problems of the development of fires in multi-story buildings in the cities of Ukraine have been identified and analyzed. The interrelationship of the following parameters was established: burning area, building floor, time of fire localization for urban settlements, which were divided into appropriate groups by population and area using cluster analysis methods. In the second chapter JUSTIFICATION OF THE METHOD OF DISCRETE SUPPLY OF FIRE-EXTINGUISHING SUBSTANCES, the materials and research methods that were used to achieve the goal and solve the tasks of the dissertation work are given. The technical characteristics of the equipment for discrete supply of fire extinguishing substances are given. The study of critical velocities and loads on a container for discrete delivery of a fire-extinguishing substance, which ensure the destruction of the container upon impact with a solid surface, is described. A description of the geometric model of the container in the shape of a sphere is given, and its finite element model is developed. The necessary properties of the material for creating a container prototype by 3D printing have been determined. The results of the impact load study on the container were obtained. The parameters of the destruction of the window pane when the container hits it were evaluated, since the discrete delivery of the fire extinguishing agent occurs everywhere in the window opening. At the same time, a geometric model, a finite-element model of the window was built, the initial conditions were determined, and the results of the calculations were analyzed. When analyzing the obtained results, it can be concluded that when the container hits the glass, both the container and the glass are destroyed, which ensures the delivery of the next containers to the center of the fire. In the third chapter, the EFFICIENCY OF THE METHOD OF REMOTE SUPPLY OF FIRE-EXTINGUISHING SUBSTANCES presents a study of the experimental verification of the effectiveness of using the method of localization of class A fires by discrete supply of fire-extinguishing substances. A study was conducted in a container-type fire module, as a result of which the results were obtained in the form of a significant decrease in the fire temperature characteristic of burning a typical fire load when the cell is localized by the proposed method. In the fourth chapter, PRACTICAL RECOMMENDATIONS FOR USING THE METHOD OF DISCRETE SUPPLY OF FIRE-EXTINGUISHING SUBSTANCE, a method of modeling the trajectory of the delivery of a container (capsule) with fire-extinguishing substance to the windows of the upper floors of buildings where a fire broke out is developed, provided that a pulse-pneumatic installation is used as a means of delivery. The departure angles of the container (capsule) are described, which ensure the intersection of the desktop and hanging trajectories at the given point of the target (in the burning window of the building). The starting speed capable of reaching the burning window of the building was calculated. The trajectory of the delivery of the container (capsule) to the window of a given height above ground level is described, provided the distance from the section of the shaft of the installation to the wall of the building is known. The value of the minimum initial departure speed of the container (capsule) was found, which ensures its delivery to the window with the fire. The effect of wind speed and direction on external ballistics is taken into account. For practical calculations, a computer program was developed for finding the values of the initial velocities and angles of the shots, provided that the initial data are entered (distance to the building, floor). It is proposed to use a tablet for operational calculations of parameters of container delivery trajectories, with the aim of effective calculation of installation parameters for discrete supply of fire extinguishing substances.