THE PURPOSE. The aim of the work is to develop an improved software and hardware complex for controlling the nozzle in the mechatronic oil analyzer PMRA-IV. The development should provide an accurate and stable supply of the test liquid to the PMR sensor when conducting multiphase analyzes of oil properties. The equipment must provide smooth movement of the nozzle in the measuring tank, be protected from electromagnetic interference, and also be compact and easy to operate. Control must be carried out using a program on a computer and a control panel.

METHOD. For development, the operating principle of the sampler was investigated. Based on the technical documentation, the operating principle of the used SD-54 electric motor was studied. The communication protocol between the computer and the microcontroller that controls the electric motor has been studied. A control algorithm for moving the pipe has been studied.

RESULTS. The result of the work is a developed compact pipe control device. Created: control software for a computer in the Labview environment, a control panel and a circuit solution to increase the noise immunity of the installation. Smooth movement of the pipe is provided using a remote control or a program on a computer via a USB connection.

CONCLUSION. Comparison with previous designs shows that the sampling device with the new control system is more accurate, stable and smooth, and has multiple control methods. The development is capable of operating stably in the presence of electromagnetic interference arising from relay switching or the magnetic field arising around the motor. The new control device allows you to quickly and accurately select the required volume of liquid into the PMR sensor.

ACTUALLY. The work addresses the topic of using electronic measuring devices in the drilling process of wells under particularly challenging and unique conditions in Antarctica. In the context of extremely low temperatures, characteristic of this region, the task is to ensure the reliable operation of electronics, which is critically important for the successful execution of drilling operations and obtaining accurate data. Special attention is given to analyzing various methods for protecting electronic devices from negative temperatures. Numerous approaches to thermal insulation are explored, and innovative materials are utilized to minimize the impact of cold air on sensitive electronic components.

OBJECT. The aim of the work is to investigate current electronic measurement systems used in drilling wells under Antarctic conditions, as well as to conduct experiments on series temperature sensors using a cooling chamber.

METHODS. The study includes thorough experiments with temperature sensors of various types and formats. Testing was conducted in specialized cooling chambers, allowing for the modeling of real conditions faced by devices in Antarctica. Furthermore, the study examines the impact of the sensor placement relative to the microchips, which can significantly affect their accuracy and reliability. An important part of the work was an experiment with electronics covered by a waterproof polymer coating. This coating not only protects the devices from moisture but also provides additional insulation against cold, which is of paramount importance in Antarctic conditions.

RESULTS. Thus, the results obtained allow conclusions to be drawn about the most effective ways to protect electronic measuring devices for drilling in challenging climatic conditions, as well as opening new horizons for further research in this area.

RELEVANCE. Today, the most pressing issue for industrial electrical machines is energy efficiency. Energy efficiency is assessed by the consumed electrical power. But the efficiency of industrial electrical units can also be assessed by other criteria. In particular, using the vibration monitoring method, it is possible to increase the energy efficiency of an electric motor by eliminating faults. Damage to electric motors (imbalance, bearing damage, shaft wear) leads to an increase in electrical losses, and, consequently, to a decrease in the energy efficiency of the motors.

THE PURPOSE. The purpose of this work is vibration monitoring of an industrial unit with the implementation of work on balancing the working disk of its electric drive. The scientific novelty of this study lies in comparing the calculated parameters of vibration characteristics with the actual values of experimental data for the KXE200 industrial fan. The practical significance of this study lies in the use of the VAST SD-23 device to reduce the vibration level of an industrial mill based on the built-in subroutine of the Balancing device.

METHODS. The method of two-plane balancing of the rotating disk of the electric drive of an industrial mill is used.

RESULTS. Vibration measurements of the industrial mill were taken before and after the balancing procedure with a significant decrease in the vibration velocity of the operating equipment. 

CONCLUSION. Dynamic balancing of industrial units with an electric drive is widely used to eliminate imbalance, which leads to a significant improvement in the operation of industrial equipment. Imbalance is one of the most common problems, so eliminating imbalance is a pressing issue in the field of non-destructive testing.

Photovoltaic energy depends on the conversion of sunlight into electricity. In recent years, the price of solar power plant equipment has dropped sharply, which has led to the increase of photovoltaic power generation in recent years. There is a trend of decreasing cost of solar panels and power plant equipment, and this has caused the increase of electricity generated from PV modules.

OBJECTIVE. To develop a system to maximize the power output of PV panels under changing solar irradiance and temperature conditions.

METHODS. This study compares two methods that can improve the working efficiency of PV modules by determining the maximum power point, ANFIS and P&O.

RESULTS. This paper explains the step-by-step process, simulation and disturbance and observation analysis by ANFIS and P&O using MATLAB/Simulink software. The P&O method works better in stable conditions, but its effectiveness drops sharply with sudden changes in lighting. On the other hand, ANFIS is more resistant to changes and is able to adapt to new conditions, which makes it a more versatile tool.

CONCLUSION. Therefore, when choosing an approach to MPP tracking, it is worth considering many factors, including operating conditions, available resources, and goals. The P&O method is an excellent solution for less demanding conditions and simple installations, while ANFIS provides solutions for more complex and dynamic applications. The main thing to emphasize is the need for a thorough assessment of the situation and the selection of the most suitable method for specific conditions. Determining the right strategy can significantly improve the performance of PV modules and increase their overall efficiency within electrical complexes.

RELEVANCE. The Arctic zone is becoming a subject of increasing interest due to climate change and the growing need for sustainable development. The introduction of renewable energy sources is becoming key to the sustainability and security of the region. The research aimed at solving the problems of development of the Arctic zone of Russia with a focus on overcoming transportation and energy constraints and introducing renewable energy sources is highly relevant.

THE PURPOSE. The study aims to develop and implement sustainable and efficient energy systems in the Arctic zone of Russia using renewable energy sources, with a focus on solar energy. To develop a simulation model of a solar array with a positioning system and demonstrate an approach to improve the efficiency of solar power plants, which is important for current technological research in renewable energy.

METHODS. Collection and analysis of measured data of solar radiation values and sunshine duration in different areas of Murmansk region. To evaluate the efficiency of solar panels application, a simulation model was developed in the program complex Matlab application Simulink.

RESULTS. The results of the study allowed to identify the potential of solar energy utilization in different areas of the Murmansk region. The performed calculations allowed to determine the optimal capacity of solar panels for the Khibiny mountain range, which contributes to the effective utilization of solar energy. A simulation model of a solar panel with the implementation of a battery positioning system to improve the efficiency of operation is presented.

CONCLUSION. The significant potential of solar energy utilization in the Arctic zone is achieved with the help of a positioning system, which holds promise for sustainable development of the region and improved energy efficiency. Adaptation of solar power plants to specific climatic conditions optimizes their performance and ensures sustainability even in the harsh climate of northern regions

RELEVANCE. Currently, there is a danger of supplying unauthorized voltage in rural electrical networks of 0.4 kV, which through reverse transformation at a transformer substation can be supplied to the 10 kV side. This can lead to fatal accidents among the staff of power grid organizations, or third parties. THE PURPOSE. Investigation of the reverse transformation mode in a rural 10/0.4 kV electric grid by means of physical modeling. METHODS. The study was conducted on a physical model of a 10/0.4 kV rural electric network using a single-phase lowpower transformer as a source of unauthorized voltage, which was connected to a low-voltage network at different distances from the model of a three-phase 10/0.4 kV transformer. In the experiments, electrical parameters were measured on the low and high voltage sides of the 10/0.4 kV transformer model. The obtained values, using similarity coefficients, were recalculated for a rural 10/0.4 kV electric grid powered by a 10/0.4 kV transformer with a capacity of 250 kVA. RESULTS. It was revealed that connecting a single-phase unauthorized voltage source to a 0.4 kV network, depending on its removal from a 10/0.4 kV transformer, leads to voltage values at the 0.4 kV output of the transformer from 11 V to 81 V (when approaching the beginning of the line departing from the transformer) in the phase to which the unauthorized voltage source is connected. On the 10 kilovolt side, the voltage varies from 234 V to 2579 V. The voltages of the other two phases on the 10 kV side range from 66 to 421 V, and on the 0.4 kV side – from 4.4 V to 22 V. CONCLUSION. The results obtained can be used as setpoints for triggering technical means of signaling and blocking reverse transformation, preventing reverse transformation in electric networks of 10/0.4 kV.

RELEVANCE Numerical simulation of the isolation modes of dry transformers is relevant due to the need to improve the reliability and efficiency of modern power systems, as it allows to optimize their operational characteristics. In turn, modern software tools provide a detailed analysis of complex physical processes, which helps to reduce the cost of field experiments and improve the economic feasibility of the proposed solutions. Predicting the insulation life using numerical modeling and emergency prevention are critically important for maintaining the stability of the power supply. purpose. Development of a numerical model of a dry transformer. Conducting studies of the influence of various operating modes on the insulation condition of dry transformers.

METHODS. To achieve this goal, the method of numerical simulation of the operation of dry transformers was used, implemented in the COMSOL Multiphysics software environment. results. The results of the study demonstrate the possibility of predicting thermal and electrical processes in the insulation of dry transformers based on modern numerical models, which helps to extend the service life of the latter. The existing operating modes of transformers make it possible to optimize their parameters to increase operational efficiency, including reducing electrical losses. The simulation results show the relationship between the parameters of the dry transformer operating modes and the state of its insulation, which contributes to the timely detection and elimination of possible malfunctions. conclusion. As a result of the study, based on the developed numerical model, the existing operating modes of a transformer with dry insulation were analyzed, and their effects were investigated taking into account the heating temperature of the transformer windings.

RELEVANCE of the study is determined by the fact that non-stationary gas-dynamic phenomena in pipelines of complex configuration are widespread in heat exchange and power equipment. Therefore, the study of the level of heat transfer of pulsating air flows in round and triangular pipes with different degrees of turbulence is an urgent and significant task for the development of science and technology.

THE PURPOSE. The influence of gas-dynamic nonstationarity (flow pulsations) on the degree of turbulence and the intensity of heat transfer of air flows in straight pipes with different cross-sectional shapes had to be assessed.

METHODS. The studies were conducted on a laboratory bench based on the thermal anemometry method and an automated system for collecting and processing experimental data. Rectilinear round and triangular pipes with identical cross-sectional areas were used in the work. Flow pulsations from 3 to 15.8 Hz were generated by means of a rotating damper. The degree of turbulence of pulsating flows varied from 0.03 to 0.15 by installing stationary flat turbulators. The working environment was air with a temperature of 22-24 ^оC moving at a speed of 5 to 75 m/s.

RESULTS. Experimental data on instantaneous values of velocity and local heat transfer coefficient of stationary and pulsating air flows with different levels of turbulence in straight pipes with different cross-sectional shapes were obtained.

CONCLUSION. It has been established that the presence of gas-dynamic non-stationarity leads to an increase in the degree of turbulence by 47-72% in a round pipe and by 36-86% in a triangular pipe. The presence of gas-dynamic non-stationarity causes an intensification of heat transfer in a round pipe by 2635.5% and by 24-36% in a triangular pipe. It has been shown that a significant increase in the degree of turbulence leads to an increase in the heat transfer coefficient of pulsating flows in a round pipe by 11-16% and, conversely, a decrease in the heat transfer coefficient by 7-24% in a triangular pipe. The obtained results can be used in the design of heat exchangers and gas exchange systems in power machines, as well as in the creation of pulsed action devices and apparatus.

RELEVANCE. The issues of efficient use of fuel and energy resources in the industrial sector of the Russian Federation have been topical for the last decades, which is confirmed by the issuance of various legislative acts and regulatory documents at the federal and regional levels. The structure of energy complexes of operating organic synthesis enterprises was formed in conditions of interconnection with external systems of energy resources supply in the period of their low internal prices. These factors have caused the low system energy efficiency of technological complexes at the present time and the need for a systematic approach to the prospective planning of energy development directions of operating enterprises. In accordance with the strategy of development and modernization of the fuel and energy complex of Russia, the directions of development of energy supply systems of organic synthesis enterprises are defined in the areas of resource conservation and creation of energy technological complexes based on efficient sources of electricity and heat supply under the conditions of improvement of the main technological processes.

THE PURPOSE. The purpose of this work is to study the heat-consuming technological units of the ethylene production line for the efficient use of thermal energy. Determine the energy saving potential and develop measures to optimize heat consumption at the considered production site.

METHODS. In this work we have studied the operation of feed water preparation unit, steam condensate pumping unit, pyrolysis gas (pyrogas) washing unit, dilution steam preparation unit of ethylene production pyrolysis section within the framework of energy inspection of the enterprise as a whole. As a result of the survey, heat losses in technological sections were assessed, material balance of technological flows was drawn up, and possible reserves of heat energy saving were determined.

CONCLUSION. It is determined that the use of heat discharged to the feed water alkaline flushing unit for heating of partially clarified water supplied to the deaerator with the installation of an additional heat exchanger at the feed water preparation and condensate pumping section will save water steam with pressure of 3.5 kgf/cm² and recycled water. At the section of water washing of pyrolysis gas, heat energy saving can be achieved by increasing the heat exchange coefficient by removing hydrocarbons from the dilution steam condensate. For the dilution steam preparation section a scheme solution is proposed, aimed at using the energy potential of steam-condensate mixture of heating steam by introducing a steam ejector unit behind the heat exchanger. The offered scheme will allow to receive economic effect 6400 Gcal/year, that in monetary terms will make 5120 thousand rubles/year, and payback period 1,2 years.

THE PURPOSE. To study the development of a non-stationary thermal boundary layer of a turbulent gas flow in the initial section of a cylindrical channel.

METHODS. The study was carried out experimentally and by means of mathematical modeling. The experiments were carried out on a rig with plasma heating of the working fluid (air). The experimental rig is an open-loop wind tunnel. The experiments were carried out at Reynolds numbers Re₀₁= 44000. The gas temperature reached 1400 K, the wall temperature increased to 700 K. The fixation of temperature fields in the boundary layer is carried out by means of chromel-alumel thermoelectric sensors. The mathematical model represents the integral equations of the boundary layer. The laws of turbulent exchange are obtained in accordance with the Prandtl model on the length of the mixing path. A two-layer model of hydrodynamic and thermal boundary layers is adopted. The use of parametric methods for calculating the boundary layer of Kutateladze-Leontiev allows us to obtain relationships for calculating the velocity and enthalpy profiles. The parameters at the boundary of the thermal conductivity sublayer, enthalpy profiles, and integral characteristics of the thermal boundary layer are determined numerically. Within the framework of the adopted model, the integral characteristics are a function of the thermal non-stationarity parameter caused by the time variability of flow temperatures.

RESULTS. The development of integral flow thicknesses during the release of the thermal load is determined. Thermal non-stationarity during the release of the load along the main flow deforms the temperature profiles, they become less filled. The results are generalized within the framework of the boundary layer theory.

CONCLUSIONS. The energy loss thickness increases relative to its stationary isothermal analog with an increase in the thermal non-stationarity parameter. The effect of non-stationarity on the energy loss thickness is within 20% at z_h ≤ 2, Re_h**=1000 and Re**=1000. 

THE RELEVANCE of the study lies in the obtained mathematical model for calculating the efficiency of separation of aerosol systems, which takes into account the uneven profile of the gas velocity in the nozzle gas separator-scrubber.

THE PURPOSE is, based on the developed mathematical model, to create an engineering methodology for calculating the efficiency of nozzle scrubber coolers together with aerosol separation using data on the hydraulic resistance of local zones of the chaotic nozzle layer and an uneven gas velocity profile.

METHODS consist in the application of a differential equation of mass transfer of aerosol particles with a local volumetric source of mass transfer and deposition of particles on the surface of a chaotic nozzle. For this purpose, the theory of the turbulent inertial mechanism of particle deposition at high velocities of aerosol systems is used. The volumetric mass source is related to the coefficient of the turbulent particle migration rate, the concentration difference and the specific surface area of the nozzle. The equation of mass transfer of particles is written in a one-dimensional formulation for a number of parallel conditional channels of the packing layer with different gas velocity. The scientific novelty consists in a mathematical model of aerosol separation, which, with low computational costs, makes it possible to predict the effect of inhomogeneity of nozzle placement and uneven gas velocity profile on the efficiency of the separation process.

RESULTS are the established effect of the uneven gas velocity profile in the packing layer on the particle concentration profile and on the efficiency of aerosol separation, which is very important when designing or upgrading scrubber coolers.

CONCLUSION. As a result of the application of the developed mathematical model and calculation methodology, the influence of different gas velocities in a chaotic packing layer on the separation efficiency of aerosol systems has been revealed. It is shown that the presence of irregularities reduces the separation efficiency by 5-33%, which must be taken into account when designing contact scrubbers with nozzles for gas purification from the dispersed phase at enterprises of the fuel and energy complex.