Global Energy

UNK RUS 7-37 Sun Q. Xu N. Pu X. Wang Z. L. Paper-based electronics and Neuromorphic Paper Chips This article has been previously published. Citation link: Q. Sun, X. Pu, Z. L. Wang Paper-based electronics and Neuromorphic Paper Chips// 10 Breakthrough Ideas in Energy for the Next 10 Years: 4rd Annual Report of the Global Energy Association on development of international research and projects in the field of energy, 2023. PP. 3–10. The original full text of the report is available at the link: https://globalenergyprize.org/en/2023/06/15/10-breakthrough-ideas-in-energy-for-the-next-10-years/ . https://engtech.spbstu.ru/article/2024.127.1/ Tsitszyun-Sun.pdf

RAR RUS 38-54 Kartashova Tatyana Prokofev Aleksei Filin A. MODERN APPROACHES TO COOLING SYSTEM DESIGN FOR AIR-COOLED TURBOGENERATORS The article discusses modern approaches to the design of the ventilation path of modern high-capacity turbine generators and the main development trends. We present an overview of current technical solutions used by world manufacturing industry leaders, as well as modern high-performance solutions used in ventilation systems of turbine generators manufactured by the Electrosila plant of JSC Power Machines. We consider the main features of modern ventilation schemes used in air-cooled turbine generators and the most effective ways to increase the cooling intensity of the core and stator winding with indirect cooling, which ensures a decrease in the temperature of the active parts while maintaining the cooling air consumption and power consumption for cooling the active parts. Design solutions are proposed to minimize ventilation losses and power costs for cooling air circulation in the rotor. It is confirmed by a numerical experiment, as well as model tests, that due to the rational design of the volute housing of the turbine generator centrifugal fan and the optimal choice of the initial flow twist at the rotor inlet, mechanical losses on turbine generator ventilation can be significantly reduced while maintaining the initial thermal state of the stator and rotor. The results of aerodynamic calculations and experiments confirmed that in high-power turbine generators with air-cooled rotor windings, it is advisable to use a rotating guide vane in combination with a stationary guide vane; the best effect is achieved when using a rotating guide vane in the form of an axial fan. doi.org/10.18721/JEST.30101 621.313.322-81 ventilation path cooling efficiency ventilation ducts turbine generator efficiency guide vane https://engtech.spbstu.ru/article/2024.127.2/ Kartashov%2C-Prokofev%2C-Filin.pdf

RAR RUS 55-68 Obukhov Sergey Davydov Denis Fedyanin Alexander MATHEMATICAL MODEL OF A BATTERY FOR THE DESIGN OF HYBRID POWER SYSTEMS BASED ON RENEWABLE ENERGY SOURCES The article is devoted to solving the problem of implementing a mathematical model of battery energy storage that has versatility, high performance and other qualities necessary for performing analysis of operating modes and design optimization of hybrid renewable energy systems. Due to the specific operating conditions of hybrid systems, as well as the presence of specific requirements for their design, most of the proposed models were unsuitable for solving design problems. The proposed model is based on a combination of the modified Shepherd model and the kinetic battery model (KiBaM), which makes it possible to simulate the operating modes of various types of batteries with algorithmic simplicity of identifying model parameters based on technical specification data. The experimental testing of the developed model showed that the model provide adequate simulation results for the change in the main parameters of dynamic modes and has high performance, which allows it to be used to solve problems of simulation modeling of modes and optimization of the hybrid power supply system equipment based on renewable energy sources. doi.org/10.18721/JEST.30102 621.355 renewable energy hybrid renewable energy systems battery energy storage mathematical model discharge characteristics https://engtech.spbstu.ru/article/2024.127.3/ Obuhov%2C-Davidov%2C-Fedyanin.pdf

RAR RUS 69-81 Prokhorov Igor Ivanov Ilya Moiseev Igor Druzhinin Vladimir UNCERTAINTIES IN PROCESSING THE EXPERIMENT TO DETERMINE THE EFFICIENCY OF THE SECTION OF THE AUTOMATIC REGULATOR RODS WHEN MEASURING THE VOID COEFFICIENT OF REACTIVITY AT THE RBMK REACTOR The article discusses the uncertainties in determining the efficiency of the automatic regulator rods when measuring the void reactivity coefficient by the method of perturbation of feed water flow at the RBMK-1000 reactor. The existing methods for assessing the effectiveness of a rod are considered. Based on the study of the results of processing measurements of the void reactivity coefficient at the Kursk, Smolensk and Leningrad nuclear power plants, a conclusion is made about the preferred option for processing the experience of weighing the rods of an automatic regulator. The estimation of the instrumental error of measuring reactivity at the power energy level is given. doi.org/10.18721/JEST.30103 621.039 RBMK-1000 reactivity void coefficient of reactivity smoothing spline standard uncertainty https://engtech.spbstu.ru/article/2024.127.4/ Prohorov%2C-Ivanov%2C-Moiseev%2C-Druzhinin.pdf

RAR RUS 82-90 Busarov Sergei S. Bakulin Konstantin INCREASING THE PERFORMANCE OF LUBRICATION-FREE, LOW-FLOW, LOW-SPEED, MEDIUM- AND HIGH-PRESSURE RECIPROCATING COMPRESSORS One of the main tasks of piston compressor machines is to provide high productivity of compressed gas. It is known that the presence of dead volume reduces the operating efficiency of any piston compressor; the effect is especially strong at significant values of the ratio of discharge pressure to suction pressure. In low-speed machines considered in this work, the pressure increase ratio exceeds 100, which actualizes work on the problem of reducing the harmful effect of dead volume on compressor performance. Dead volume can be reduced by eliminating the linear dead volume, which takes up its majority. Experimental studies of a design in which a rubber (elastomer) disc is installed on the end surface of the piston facing the valve plate are considered. The conducted studies showed that the use of a rubber disk with the possibility of touching the proposed design of the valve plate piston almost completely eliminates linear dead volume. In this case, the increase in the feed rate can reach 20%. doi.org/10.18721/JEST.30104 621.512.2 low-speed compressor dead volume linear dead volume flow rate workflow efficiency https://engtech.spbstu.ru/article/2024.127.5/ Busarov%2C-Bakulin.pdf

RAR RUS 91-107 Fedyukhin Gasho Evgeniy METHODOLOGICAL APPROACHES TO THE ANALYSIS OF ENERGY-ECOLOGICAL METABOLISM OF CITIES Urban energy systems are subject to the intense and multidirectional influence of a variety of technical, environmental, economic, social and cultural factors. The task of effective strategic planning of urbanized territories is one of the most important challenges facing our civilization in the 21st century. The key to solving this problem lies in the development of an interdisciplinary and scientifically based approach to the analysis of urban metabolism from the standpoint of energy efficiency and environmental safety. There are not many scientific papers on urban energy in the field of urban planning. More often, attention is paid to social, cultural, economic, environmental or transport aspects. At the same time, the shortage of electrical and thermal capacities in a number of Russian cities, high wear of utility networks, problems with the removal and effective disposal of waste leads to the need for a systematic approach to analyze the energy flows of the city and the associated environmental damage. This article analyzes the enlarged energy indicators of megacities of the world with the development of a methodological approach to the study of the energy-ecological metabolism of the city. doi.org/10.18721/JEST.30105 504.052 urban metabolism urban planning municipal energy system energy consumption energy conservation https://engtech.spbstu.ru/article/2024.127.6/ Fedyuhin%2C-Gasho.pdf

RAR RUS 108-116 Diteleva Anna Sleptsov Vladimir Kukushkin Dmitriy THIN-FILM TECHNOLOGY FOR THE CREATION OF PROMISING ELECTRODE MATERIALS FOR HYBRID CAPACITORS This work is devoted to the development of a thin-film technology for manufacturing a promising electrode material based on a highly porous carbon matrix. The paper presents the developed design of an electrode material based on a highly porous carbon material for energy storage devices with a double electric layer and for hybrid capacitors in which energy is accumulated both in a double electric layer and due to electrochemical reactions. It is shown that the developed thin-film technology is very promising for the purpose of increasing energy intensity in contrast to the traditional thick-film technology, and also allows you to create capacitor cells with parameters exceeding the parameters of existing supercapacitors (ionistors). The prospect of using the developed electrode material design and thin-film technology for hybrid capacitors with a specific energy consumption of over 300 Wh/kg is also shown. doi.org/10.18721/JEST.30106 621.355 electrode materials hybrid capacitor nanoparticles energy storage carbon fiber highly porous matrix https://engtech.spbstu.ru/article/2024.127.7/ Diteleva%2C-Sleptsov%2C-Kukushkin.pdf

RAR RUS 117-135 Sysoev Artem Iudin Dmitry Rakov Vladimir Emelyanov Aleksey Klimashov Vitaly B-7916-2013 6601971248 0000-0002-1173-8727 Peter the Great St. Petersburg Polytechnic University, Russia Korovkin Nikolay nikolay.korovkin@gmail.com

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

NUMERICAL SIMULATION OF HIGH-CURRENT ATMOSPHERIC DISCHARGES WITH CONSIDERATION OF PLASMA CHANNELS THERMODYNAMICS. PART 2. ANALYSIS OF SIMULATION RESULTS The article presents the second part of the study devoted to the modeling of high-current lightning discharges. The first part [part 1] describes a model approach taking into account discharge channels thermodynamics that allows us to relate conductivity and the current-carrying radius of leader segments to their temperature. The study presents and analyses simulation results covering all stages of the high-current lightning development. It is shown that the model is capable of reproducing currents characteristic of high-current lightning discharges with amplitudes up to tens of thousands of amperes. Simulation results let us formulate a new scenario of development of compact intracloud discharges and initial breakdown pulses based on collective dynamics of a system consisting of a large number of interconnected discharge channels developing in a parallel. In particular, it is demonstrated that current pulses characteristic of compact intracloud discharges and initial breakdown pulses can form as a result of evolution of a network of low-temperature (streamer) plasma channels. Inside this network, a hot well-conducting leader frame forms drawing the system currents onto itself. At the same time, at all the stages of discharge development the relative fraction of leader sections does not exceed a few percent of the total number of channels in the current system. doi.org/10.18721/JEST.30107 537+519.6 compact intracloud discharge initial breakdown pulses streamers leaders hierarchical networks of plasma channels discharge channels thermodynamics lightning initiation negative leader steps numerical simulation https://engtech.spbstu.ru/article/2024.127.8/ Sisoev%2C-Iudin%2C-Rakov.pdf

RAR RUS 136-145 Erutin Danil Popovich Anatoliy popovicha@mail.ru Sufiiarov Vadim SELECTIVE LASER MELTING OF COBALT-BASED AMORPHOUS ALLOY The paper presents the results of the study of microstructure and phase composition, as well as the influence of scanning strategy and thickness of the applied powder layer during selective laser melting on the relative density of a compact amorphous-nanocrystalline soft-magnetic alloy based on cobalt 86KGSR. It is shown that the application of an alternative scanning strategy can increase the relative density of the compact material. The X-ray diffraction analysis as well as optical and scanning electron microscopy provided data on the phase composition, relative density and microstructure of the alloy. The results of the study can be used for further research and development of a technology for obtaining composite amorphous-nanocrystalline soft-magnetic cobalt-based materials by selective laser melting. doi.org/10.18721/JEST.30108 621.762 selective laser melting amorphous alloy magnetically soft alloy scanning strategy additive technology cobalt alloy https://engtech.spbstu.ru/article/2024.127.9/ Erutin%2C-Popovich%2C-Sufiyarov.pdf

RAR RUS 146-157 Dasaev Marat Sokolov Ivan Ryzhenkov Oleg Grigoryev Sergey Likhaeva Alena Ataullin Marat APPLICATION OF CR-BASED PVD COATINGS OF DIFFERENT THICKNESSES FOR RETARDING HYDROGEN EMBRITTLEMENT OF STEEL In the context of active development of alternative energy sources, the problem of hydrogen embrittlement of critical structural elements undoubtedly requires attention. Deterioration of strength characteristics of structural materials in contact with hydrogen-containing media significantly increases the requirements for their reliability and reduces the technical and economic feasibility of using hydrogen. This paper presents the results of metallographic studies and mechanical tests of experimental St20 steel samples with a barrier coating with thickness of≈2 μm and ≈4 μm on the basis of chromium (Cr), applied using PVD (Physical Vapour Deposition) technology. Analysis of morphology and structure of the coating, as well as fractograms of the fracture surface of the experimental samples showed the absence of structural changes during hydrogenation of the samples. According to the results of tensile tests, the positive effect of using barrier coatings of greater thickness was noted. Experimental samples with barrier coating of greater thickness showed less deterioration of strength characteristics, compared to the control hydrogenated sample without barrier coating. We observed a twofold decrease in the rate of deterioration of strain values and a fourfold decrease in the rate of deterioration of the tensile strength. doi.org/10.18721/JEST.30109 620.1 hydrogen embrittlement steels PVD technology barrier coatings mechanical testing https://engtech.spbstu.ru/article/2024.127.10/ Dasaev%2C-Sokolov%2C-Rizhenkov%2C-Grigorev%2C-Lihaeva%2C-Ataullin.pdf