The dissertation work is a completed scientific research in which the actual scientific task of increasing the efficiency of the contact cooling system of the mine turbocompressor by choosing rational parameters of the system is solved.
The purpose of the work is to establish dependencies for determining rational parameters from the initial conditions and modes of operation of the turbocompressor of the contact system cooling devices of mine turbocompressors.
Thus, based on the analysis of literary sources, it was found that pneumatic energy is widely used in many industries. Along with steam, electricity, mechanical and hydraulic energy, compressed air is used to automate and mechanize various production processes. Compressed air is one of the most common energy carriers in industrial enterprises, and the devices associated with its distribution and processing are an energy-intensive complex industrial energy system, the indicators of technological processes in which compressed air is used depend on its level of perfection. For the production of compressed air on an industrial scale, turbo compressors are mainly used. Compressed air cooling is a mandatory condition for their normal operation. The compressed air cooling system is used not only for dehumidification, but also to reduce energy consumption. Processes that occur in an ideal compressor: isothermal, adiabatic and polytropic. It was found that the most important feature of the isothermal process is that the work spent on gas compression is less than in other compression processes. This feature determines the economic feasibility of cooling compressed gas in compressors and the desire to approach an isothermal process. Most often, shell and tube heat exchangers are used for cooling, but during the operation of turbo compressors equipped with shell and tube air coolers, there is a rapid deterioration of air cooling efficiency due to intensive contamination of the heat exchange surfaces of air coolers. This leads to a change in the characteristics of uncooled sections, which is accompanied by a decrease in the performance of turbochargers and an increase in their energy consumption. Prospective coolers are contact heat exchangers. One of the most promising devices for contact cooling of compressed air in turbocompressors is a venturi tube - a centrifugal separator, as it combines high heat and mass exchange and relatively small hydraulic resistance. It was found that the rational parameters of contact air coolers are determined only for the nominal operating mode of the turbocompressor under normal initial conditions. Since the cross-section of the Venturi tube neck has the greatest influence on the efficiency of the contact cooling system, in order to maintain a reasonable air velocity, it is suggested to use a Venturi tube with a neck cross-section regulated by means of a special cone. This makes it possible to maintain a minimum volume flow at the inlet to the uncooled section of the turbocharger when the performance of the turbocharger changes, as well as when the initial temperatures and pressures of air and water temperature change. It is also important to maintain rational water consumption. The amount of water that provides the air cooling mode with simultaneous air drying, which is much better than the humidification mode, will be rational.
In the course of analytical studies, a mathematical model of rational parameters of contact air coolers was developed depending on the initial conditions and modes of operation of turbocompressors, analytical dependencies were obtained for determining the rational cross-section of the Venturi tube neck and cooling water consumption.
A laboratory installation for contact cooling of compressed air was developed for conducting laboratory research. As a result of laboratory studies, the high efficiency of the contact method of cooling compressed air in turbocompressors has been proven. The rational parameters of the system were identified and the adequacy of the mathematical model of the rational parameters of contact air coolers depending on the initial conditions and operating modes of the turbocompressors was proven.
As a result of the research, the design of contact cooling system devices, recommendations for the selection of equipment for the contact cooling system of mine turbocompressors, the method of calculation of contact cooling system devices of turbocompressors were developed. The economic efficiency of the contact cooling system with an adjustable throat has also been proven.
Thus, the goal set in the work was achieved due to the improvement of the contact cooling system and the obtained dependences of the rational parameters on the initial conditions and modes of operation of the turbocompressors.
