Preview

Safety and Reliability of Power Industry

Advanced search
Open Access Open Access  Restricted Access Subscription Access
Vol 17, No 4 (2024)
View or download the full issue PDF (Russian)
https://doi.org/10.24223/1999-5555-2024-17-4

GENERAL ISSUES RELATED TO RELIABILITY AND SAFETY OF THE POWER INDUSTRY

244-252 132
Abstract

A study was conducted on the peculiarities of electric energy transport in the power supply systems of the PJSC “Rosseti Volga” – “Orenburgenergo” branch for the period 2020 – 2023. The structure of the company is described, the characteristics of the main elements of the studied electric networks are provided, and an assessment of the balance of electric energy transmission in and out of the company's networks is presented. Based on information published in the open press, an analytical assessment of the accident rate in the company's electrical networks was carried out on a monthly basis for each year of the study period. The influence of seasonal factors on the number of emergencies during the study period is examined. The consequences of emergency shutdowns, in terms of the amount of electrical energy undersupplied to consumers, are evaluated. Based on the proposed classification, an analysis of the failure intensity was performed, and the percentage of failures of various intensities was established. Based on data for the first half of 2020 and 2023, a detailed analysis of the main causes of damage to elements of the electrical networks was carried out. The percentage ratio of the number of failures attributed to the most common causes to the total number of outages during the study period was established. The data obtained on the causes of emergency outages were compared with similar indicators in the electrical networks of other branches of PJSC Rosseti Volga. General scientific methods, as well as numerical analysis methods, were used in conducting the study. Visualization of the results of the analysis is presented using the technical capabilities of the MATLAB graphics editor. The results of this research may be of interest to the management of electric grid companies, as well as to researchers and engineers engaged in studies related to the reliability of power supply during the transmission of electric energy via overhead power lines.

253-260 171
Abstract

The article discusses general issues related to ensuring vibration reliability of steam turbines, various factors that can cause increased vibration of turbine units, including design, technological, and operational factors. Special interest is given to hidden factors that can be detected only indirectly through analytical methods by studying the complex “turbine unit – foundation – base” (TFB) system. For example, increased stresses in the structure and, accordingly, zones of probable crack development due to seismic subsidence of supports or high vibrations can be detected. Such defects can be the subject of study in so-called predictive analytics. It is shown that ensuring vibration reliability requires a systematic approach. Among the many causes of vibration, it is always necessary to identify the most significant primary causes. Requirements for ensuring reliability at different stages of the creation and operation of a turbine unit are formulated. A stability diagram of the turbine unit is provided, where the stability boundaries are presented for the first time as functions of the main parameter of the working fluid flow through the turbine unit. It is shown that the foundation requirements in RD 34 15.078-91 are outdated and do not meet modern reliability standards for turbine units. The main defects in the assembly of the shaft line are listed, and the primary requirements for the assembly of rotors in half-couplings are formulated. The need for machining bearing liners to create a cylindrical boring surface is emphasized, and scraping the surface for this purpose is not recommended. For the first time, the need for grinding the ends of half-couplings after their deformation due to bolt tightening to half the yield strength is indicated. This is important because residual deformations are detected at the ends of the half-couplings, which hinder the quality of the half-coupling fit.

261-266 154
Abstract

The atomic industry of Russia remains one of the key sectors ensuring the country’s energy security and economic growth. However, with the imposition of international sanctions, the industry has faced serious challenges such as restricted access to technologies and cooperation with traditional partners. In response, the Russian government has actively developed support programs and encouraged the advancement of domestic technologies to ensure the industry’s independence from foreign suppliers.
Key support measures have included import substitution programs and innovative developments. Companies like Rosatom have begun creating their own high-tech solutions to replace foreign counterparts. An important area of focus has been the development of small modular reactors (SMRs), which can provide energy to remote regions and enhance the autonomy of the energy infrastructure.
The government offers tax benefits and subsidies for acquiring innovative technologies, including digital solutions and artificial intelligence, which enhance managerial efficiency and reduce costs for nuclear power plants. International cooperation with China, India, and Turkey strengthens Russia's position in the global nuclear market. Despite sanctions, the country continues to expand its influence in the nuclear energy sector. The construction of nuclear power plants in Turkey and Bangladesh highlights the industry's export potential.
In conclusion, the development of Russia’s atomic industry will depend on its ability to implement innovative technologies, continue international cooperation, and adapt to the challenges posed by sanctions. Government support plays a crucial role in creating the conditions for technological independence; modernizing the industry, and strengthening its competitiveness in the global market.

DESIGN, RESEARCH, CALCULATIONS

267-271 143
Abstract

Radar probing is a system for experimental study of various physical objects and environments, widely used both in longrange objects (for example, in remote sensing of the Earth, atmosphere and space objects), and in short-range objects: non-destructive testing, medical diagnostics, etc. The operating principle is based on the Doppler effect. It allows recording the movement of surface areas in the range of speeds from several nanometers per second to transonic, with registration of the frequency spectrum of oscillations. The main advantages of the method are the contactless, non-disturbing nature of measurements, their continuity, allowing for real-time diagnostics, high potential accuracy, as well as the ability to determine the internal structure of objects and environments that are transparent to probing radiation. The measuring complex developed by VtBIS LLC based on the system allows determining the position of the blades relative to each other in a working turbine at a rotation frequency of up to 15,000 rpm, which allows measuring the natural frequencies of turbine blade oscillations and the amplitudes of forced blade oscillations, as well as measuring the amplitude-frequency characteristics of forced oscillations of a blade oscillating in an external alternating magnetic field. The operability and reliability of such measuring equipment is confirmed by experimental data. This makes it possible to use it as a tool for studying the state of a blade assembly in gap measurement systems or for the discrete-phase method in order to improve the efficiency of its operation.

272-279 187
Abstract

The traditional manufacturing process for shrouded impellers in centrifugal compressors is characterized as a multi-stage process, which involves attaching blades to the impeller and welding a cover disk to the blades. Despite the extensive experience gained with traditional manufacturing methods, including laser welding, transitioning to additive manufacturing technology offers significant advantages: it enables the production of a shrouded impeller as a single, seamless part with no joints, thereby reducing the likelihood of defects. This article examines the stress and deformation behavior of a shrouded impeller in a centrifugal compressor operating at high rotational speeds (60400 rpm). A three-dimensional model was created, and a strength analysis was conducted to evaluate the structural integrity of the impeller. The calculations were performed using the ANSYS Workbench 2019 software. The results identified the locations of maximum stress concentration, which occur at 30 – 40% of the main blade length and near the leading edges of the splitters. In these regions of stress concentration, the ductility of the impeller material was considered. The primary mechanical properties of the additive materials used for the impeller — stainless steel grade 316, aluminum alloy AlSi10Mg, titanium alloy Ti-6Al-4V, and martensitic steel 17-4PH — were specified. The analysis showed that the titanium alloy Ti-6Al-4V best satisfies both the strength and technological requirements.
The conducted analysis facilitated the selection of a suitable material for the rotating components of high-speed turbomachinery.

280-288 148
Abstract

Every year, increasing attention is paid to the use of unconventional and renewable energy sources for heating. Promising sources of heat supply are steam compression heat pumps, for which soil, atmospheric air, groundwater, ventilation emissions, etc. are used as low-potential heat sources. Due to its accessibility, air is one of the most common sources of heat for such installations. The efficiency of air heat pumps depends significantly on climatic conditions, and in practice they are used in conjunction with an additional energy source. This study evaluates the efficiency of such a combined system using the example of a heat supply system for a residential building under various climatic conditions in Russia. The coefficient of performance (COP) of a heat pump is considered as the main indicator of its efficiency. The load on the heating system for each region was determined using the thermal balance method. The study utilized the values of the COP obtained from testing. It is established that the average annual COP of the heat pump for the considered climatic conditions ranges from 1.76 to 1.98 when operating the heat supply system with a temperature schedule of 80/60°C, and it functions effectively at this temperature schedule down to an outdoor air of no lower than – 16°C; at lower temperatures, the load is covered by an additional source. In addition, the annual energy costs for operating the heat supply system are calculated, and the distribution of this component between the heat pump (48% – 97.6%) and the additional source is determined. The feasibility of using heat pumps in non-gasified areas is determined by the electricity tariff.

289-298 137
Abstract

The issue of mixing fuel oil with water, i. e. emulsification, is considered. Emulsified fuel of the “water-fuel oil” type is a promising alternative fuel, as it causes water to boil at high temperatures, which can improve the atomization of the fuel spray. The process of heating and evaporation of a droplet of emulsified fuel depends on the diffusion and coalescence of the smallest water particles in the fuel oil, which occur during heating. The article presents a model that accounts for the process of water diffusion in droplets of emulsified fuels, as well as the physical properties of the entire medium. The model incorporates these important physical phenomena and offers an effective method for calculating the ratio of emulsion components. It is designed to describe the heating and evaporation of droplets of emulsified fuel, such as “water-fuel oil”. The process of water coalescence is simplified by the fact that dispersed water droplets instantly combine into a single water subdroplet in the center of the fuel oil droplet. During the calculations, the proportions of each component are taken into account; in addition to the combustion of the carbon content of the fuel oil, it is necessary to consider the heat release of water vapor, the release of hydrogen, the dissociation of water and the thermal effect of hydrogen combustion. These processes occur in the same proportions as in the water-fuel oil emulsion. To address the tasks at hand, the ANSYS CFX module was selected, which allows for the simulation of chemical reactions and combustion processes associated with liquid flow. This will enable a detailed study of the phenomena occurring and help determine the optimal parameters of the water-fuel oil emulsion, thereby increasing operational efficiency. Based on the proposed model, the combustion process in the furnace volume as a function from the water content in the emulsified fuel was analyzed.

299-305 128
Abstract

The study explores the potential for reducing the energy and material intensity of urban systems that supply residential, public and industrial facilities with heat, electricity and gas. It demonstrates that these improvements contribute significantly to addressing global challenges related to maintaining an acceptable climate on the planet. While the bulk of energy generation relies on organic fuels, increasing the energy efficiency of urban energy supply systems by 3% is equivalent to a 1% reduction in production-related carbon emissions. One of the large and materialintensive devices used in energy generation, gas distribution, and in the chemical and food industries, as well as in various municipal enterprises, is the air filtering and conditioning system (AFCS). In recent decades, the influx of numerous varieties of filters from foreign companies into the Russian market has led to the development of AFCS designs featuring porous filters at both stages of purification, while cyclone stages have been relegated to the category of obsolete and imperfect technology. It is shown that the cyclone stages in AFCSs possess sufficient potential for improving cleaning efficiency and can substantially reduce the dimensions and material consumption of air cleaning systems. A combined (2D – 3D) method for numerical study of cyclone element blocks is proposed, simplifying the research process and reducing resource consumption. A numerical model of a cyclone element with a filter insert has been created and tested, demonstrating the capability of air filtering and conditioning systems of this type to achieve filtration classes E7 and higher.

SOCIOLOGY IN ENERGY INDUSTRY

306-312 189
Abstract

This article presents a communication model for integrating blockchain-technology into the Russian energy system, which takes into account the restraining factors, limitations on blockchain development, the legal environment, as well as both domestic and international experience. The model aims to improve resource management, enhance security and efficiency in the energy sector, and create advantages for all stakeholders. The model is based on the principles of the author's PR concept of integrated strategic communications (ISC), ensuring a comprehensive approach to interacting with various interest groups and effectively addressing challenges arising from the introduction of new technologies in the energy sector.

The research includes analysis of theoretical sources and practical experience of Russian and foreign companies using blockchain in power industry. Special attention is given to the analysis of communication strategies employed by PJSC Gazprom Neft in blockchain-technology projects.

The results of the study can be used to improve the reputation and optimize processes in Russian energy companies, as well as to have innovations implemented by government structures. The development of a communication model for blockchain integration, considering industry-specific features and ISC principles, opens up prospects for further research and practical steps in the energy sector.



ISSN 1999-5555 (Print)
ISSN 2542-2057 (Online)