Pub Date : 2023-03-27DOI: 10.18664/1994-7852.203.2023.277905
V. Nerubatskyi, O. A. Plakhtii, D. Hordiienko, H. Khoruzhevskyi, Maryna Vitaliyivna Philipjeva
The methodology for modeling static and dynamic power losses in power IGBT and MOSFET transistors in the Matlab and Multisim software environments is given. It is shown that when modeling switching processes in power transistors, Matlab / Simulink does not allow determining the dynamic components of power losses, namely, the energy of turning on the transistor, the energy of turning off the transistor, as well as the recovery energy of power diodes. At the same time, the simulation of static power losses of power diodes and transistors in Matlab/Simulink is carried out with a significant error due to incorrect representation of the current-voltage characteristics. It is shown that for a more correct and accurate simulation of the operation of power transistors, including power losses in power switches, it is more appropriate to conduct simulations in the Multisim software environment, which takes into account more than 47 parameters during simulation, including temperature characteristics, parasitic input and output capacitances and inductances, nonlinearities of current-voltage characteristics and others. In Multisim, a circuit of a half-bridge inverter with power MOSFETs controlled by the IR2104PBF driver has been developed. It is shown that the switching of power transistors is significantly influenced by the parameters of the driver microcircuit, namely the size of the storage capacitor of the driver, as well as the value of the active resistance of the gate resistor. It is shown that the simulation in Multisim correctly displays the transient processes of turning on and off power transistors and reverse recovery of diodes, which allows determining the dynamic losses of power transistors and power diodes.
{"title":"RESEARCH THE ACCURACY OF MODELING POWER LOSSES IN POWER DIODES AND TRANSISTORS","authors":"V. Nerubatskyi, O. A. Plakhtii, D. Hordiienko, H. Khoruzhevskyi, Maryna Vitaliyivna Philipjeva","doi":"10.18664/1994-7852.203.2023.277905","DOIUrl":"https://doi.org/10.18664/1994-7852.203.2023.277905","url":null,"abstract":"The methodology for modeling static and dynamic power losses in power IGBT and MOSFET transistors in the Matlab and Multisim software environments is given. It is shown that when modeling switching processes in power transistors, Matlab / Simulink does not allow determining the dynamic components of power losses, namely, the energy of turning on the transistor, the energy of turning off the transistor, as well as the recovery energy of power diodes. At the same time, the simulation of static power losses of power diodes and transistors in Matlab/Simulink is carried out with a significant error due to incorrect representation of the current-voltage characteristics. It is shown that for a more correct and accurate simulation of the operation of power transistors, including power losses in power switches, it is more appropriate to conduct simulations in the Multisim software environment, which takes into account more than 47 parameters during simulation, including temperature characteristics, parasitic input and output capacitances and inductances, nonlinearities of current-voltage characteristics and others. In Multisim, a circuit of a half-bridge inverter with power MOSFETs controlled by the IR2104PBF driver has been developed. It is shown that the switching of power transistors is significantly influenced by the parameters of the driver microcircuit, namely the size of the storage capacitor of the driver, as well as the value of the active resistance of the gate resistor. It is shown that the simulation in Multisim correctly displays the transient processes of turning on and off power transistors and reverse recovery of diodes, which allows determining the dynamic losses of power transistors and power diodes.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133707182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-27DOI: 10.18664/1994-7852.203.2023.277952
Ruslan Viznyak
The article considers the factors influencing the strength of gondola cars during unloading on rotary car dumpers, before which a preliminary careful analysis of their characteristic damage and malfunctions was carried out. The calculated schemes of the system design are constructed and the analytical determination of the inertial components of the dynamic overturning process is performed. Initial recommendations for the design of the body structure, which is exposed to high dynamic loads during the mandatory unloading of the freight vehicle. The issue of fleet conservation is important for owners and operators of rolling stock, based on the balance of working and non-working fleet. The main cause of damage to the load-bearing structure of the gondola is non-compliance with the content of regulatory documents when performing loading and unloading operations. Unloading of gondola cars in the method of overturning was introduced at industrial enterprises in the last century during the intensive industrialization of the German experience and supply of equipment and is now successfully carried out using special technical devices - stationary rotor tippers. According to the results: acceleration of the PV body occurs at an angle of rotation of about 60°; the maximum values of accelerations are observed at an angle of rotation of 125°. This is done at the final stage of the flow of the load, because the final component of the full angle of rotation no longer affects the dynamics, because the load in the body is not a large part. The results of theoretical research at the design stage of the PV allow to take into account possible dynamic factors due to the overturning of the PV body, and prevent probable damage, assess the margin of safety and reliability of the body structure, which will ultimately reduce maintenance costs and increase life cycle load.
{"title":"THE SIGNIFICANCE OF DYNAMIC FORCES ACTING ON A GONDOLA CAR WHEN UNLOADING BY A ROTARY CAR DUMPER","authors":"Ruslan Viznyak","doi":"10.18664/1994-7852.203.2023.277952","DOIUrl":"https://doi.org/10.18664/1994-7852.203.2023.277952","url":null,"abstract":"The article considers the factors influencing the strength of gondola cars during unloading on rotary car dumpers, before which a preliminary careful analysis of their characteristic damage and malfunctions was carried out. The calculated schemes of the system design are constructed and the analytical determination of the inertial components of the dynamic overturning process is performed. Initial recommendations for the design of the body structure, which is exposed to high dynamic loads during the mandatory unloading of the freight vehicle. The issue of fleet conservation is important for owners and operators of rolling stock, based on the balance of working and non-working fleet. The main cause of damage to the load-bearing structure of the gondola is non-compliance with the content of regulatory documents when performing loading and unloading operations. Unloading of gondola cars in the method of overturning was introduced at industrial enterprises in the last century during the intensive industrialization of the German experience and supply of equipment and is now successfully carried out using special technical devices - stationary rotor tippers. According to the results: acceleration of the PV body occurs at an angle of rotation of about 60°; the maximum values of accelerations are observed at an angle of rotation of 125°. This is done at the final stage of the flow of the load, because the final component of the full angle of rotation no longer affects the dynamics, because the load in the body is not a large part. The results of theoretical research at the design stage of the PV allow to take into account possible dynamic factors due to the overturning of the PV body, and prevent probable damage, assess the margin of safety and reliability of the body structure, which will ultimately reduce maintenance costs and increase life cycle load.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128958080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273623
A. Sulym
The article deals with the main existing approaches to determining the parameters of on-board capacitive energy storages for electric rolling stock and their comparative analysis. The advantages and disadvantages of each of the ten considered approaches are set out. Each of the approaches is described and their comparative analysis is performed according to such criteria as the level of research complexity, the financial component of research, the possibility of taking into account the real operation conditions of electric rolling stock while carrying out the research, the method of evaluating the parameters of the on-board capacitive energy storage, the possibility of determining rational parameters, the universality of the approach, considering the technical and economic component and limitations on weight and size of indicators. The power and energy capacity of on-board capacitive energy storage devices, their weight-size indicators when applying each of the considered approaches for the same given operating conditions of the electric rolling stock are determined. A five-car articulated vehicle with an asynchronous traction drive and recovery systems, consisting of metro cars of models 81-7080, 81-7081, 81-7081-01, was chosen as the electric rolling stock. The experimental section between the final stations of the SviatoshynskBrovary line of the utility company “Kyivskyi Metropolitan” was chosen as the specified operating conditions. The payback period and the impact of storage systems with the selected parameters on the performance indicators of the given electric rolling stock while using various approaches are determined. It was found that the most developed approaches, the key point of which is the selection of rational parameters using theoretical research with the help of application-specific software and multi-criteria evaluation methods. The feasibility of using a multi-criteria approach, which allows choosing rational parameters of the capacitive energy storage for electric rolling stock based on three important evaluation criteria, i.e., weight, volume and payback period, is demonstrated. It was established that it is rational to use an on-board capacitive energy storage device of low power and energy intensity.
{"title":"COMPARATIVE ANALYSIS OF APPROACHES TO DETERMINING THE PARAMETERS OF A CAPACITIVE ENERGY STORAGE FOR ELECTRIC ROLLING STOCK","authors":"A. Sulym","doi":"10.18664/1994-7852.202.2022.273623","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273623","url":null,"abstract":"The article deals with the main existing approaches to determining the parameters of on-board capacitive energy storages for electric rolling stock and their comparative analysis. The advantages and disadvantages of each of the ten considered approaches are set out. Each of the approaches is described and their comparative analysis is performed according to such criteria as the level of research complexity, the financial component of research, the possibility of taking into account the real operation conditions of electric rolling stock while carrying out the research, the method of evaluating the parameters of the on-board capacitive energy storage, the possibility of determining rational parameters, the universality of the approach, considering the technical and economic component and limitations on weight and size of indicators. The power and energy capacity of on-board capacitive energy storage devices, their weight-size indicators when applying each of the considered approaches for the same given operating conditions of the electric rolling stock are determined. A five-car articulated vehicle with an asynchronous traction drive and recovery systems, consisting of metro cars of models 81-7080, 81-7081, 81-7081-01, was chosen as the electric rolling stock. The experimental section between the final stations of the SviatoshynskBrovary line of the utility company “Kyivskyi Metropolitan” was chosen as the specified operating conditions. The payback period and the impact of storage systems with the selected parameters on the performance indicators of the given electric rolling stock while using various approaches are determined. It was found that the most developed approaches, the key point of which is the selection of rational parameters using theoretical research with the help of application-specific software and multi-criteria evaluation methods. The feasibility of using a multi-criteria approach, which allows choosing rational parameters of the capacitive energy storage for electric rolling stock based on three important evaluation criteria, i.e., weight, volume and payback period, is demonstrated. It was established that it is rational to use an on-board capacitive energy storage device of low power and energy intensity.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123688383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273666
Anna Leonidovna Kravets, A. Kravets, O. Shapatina
The article considers increasing the speed of freight delivery by rail using the existing capacity, infrastructure and resources. Possible options and technologies to speed up the delivery of freight are analyzed on the basis of experience of other countries. A mathematical solution to the optimization problem is proposed – achieving a certain level of service with minimal costs associated with the downtime of handling facilities. The purpose of the study is to determine to what extent such characteristics as transit time, queueing time for loading of goods, etc., can change during the transition from conventional freight transportation to high-speed one. Mathematical simulation methods were used to estimate the change in the characteristics of freight transportation when the speed increases. Freight transportation was considered as a mathematical queuing system (QS). Accordingly, the characteristics of two QSs with the same intensity of the order workflow and different intensities of the service workflow at a service are compared. That is, the characteristics of movement of freight trains in the transition from regular traffic to high-speed traffic are compared. The formulas proposed in the paper will allow to study the dependence of the number of freight trains and the downtime of handling facilities on the intensity of the service workflow, i.e. on the speed of movement. It will also allow to determine intensity of a service workflow which is necessary to achieve the given average time which an order stays in system, i.e. to find the speed of freight traffic required to achieve the given average trip time. Conducting this research will allow to conclude about advantages or disadvantages of transportation by high-speed freight trains in comparison with conventional freight trains and expediency of their introduction on certain sites.
{"title":"INCREASING THE SPEED OF FREIGHT TRANSPORTATION BY MEANS OF OPTIMIZATION","authors":"Anna Leonidovna Kravets, A. Kravets, O. Shapatina","doi":"10.18664/1994-7852.202.2022.273666","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273666","url":null,"abstract":"The article considers increasing the speed of freight delivery by rail using the existing capacity, infrastructure and resources. Possible options and technologies to speed up the delivery of freight are analyzed on the basis of experience of other countries. A mathematical solution to the optimization problem is proposed – achieving a certain level of service with minimal costs associated with the downtime of handling facilities. The purpose of the study is to determine to what extent such characteristics as transit time, queueing time for loading of goods, etc., can change during the transition from conventional freight transportation to high-speed one. Mathematical simulation methods were used to estimate the change in the characteristics of freight transportation when the speed increases. Freight transportation was considered as a mathematical queuing system (QS). Accordingly, the characteristics of two QSs with the same intensity of the order workflow and different intensities of the service workflow at a service are compared. That is, the characteristics of movement of freight trains in the transition from regular traffic to high-speed traffic are compared. The formulas proposed in the paper will allow to study the dependence of the number of freight trains and the downtime of handling facilities on the intensity of the service workflow, i.e. on the speed of movement. It will also allow to determine intensity of a service workflow which is necessary to achieve the given average time which an order stays in system, i.e. to find the speed of freight traffic required to achieve the given average trip time. Conducting this research will allow to conclude about advantages or disadvantages of transportation by high-speed freight trains in comparison with conventional freight trains and expediency of their introduction on certain sites.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134209273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273613
V. Kozar, V. Bakhariev, N. Halchenko, Y. Dorozhko
The article presents the results of conceptual modeling of the geospatial database for monitoring electromagnetic pollution of settlements. Recently, the world has seen a rapid increase in the number of sources and the level of electromagnetic radiation. This can negatively affect people's health and their environment. The analysis of the publications showed that today researchers have formed a theoretical base for assessing the impact of electromagnetic radiation on people and the environment, developed models of the propagation of electromagnetic waves, ways and methods of protection against their harmful effects. However, not enough attention has been paid to monitoring the electromagnetic pollution of settlements. Systematic measurements of electromagnetic field levels are carried out only by individual EU countries Systematic control of this type of pollution is not carried out in Ukraine, there are no regulatory documents regarding the procedure for its monitoring, but the maximum permissible levels of electromagnetic fields for the population are established. Data on the distribution of electromagnetic fields are interdisciplinary in nature and necessarily contain an indication of the location of objects. For their effective processing, it is advisable to use geo-information technologies. Based on the results of the analysis of the subject area of electromagnetic pollution monitoring, a conceptual data model was developed. It is described using UML tools. The model contains two sets of data. The basic set of geospatial data includes information about buildings of various purposes, land plots, streets, highways, railways, engineering communications, relief, soils, hydrography, territory zoning, facility addresses. The profile set includes data on electromagnetic radiation sources and their sanitary protection zones, control points, the results of calculations and measurements of radiation parameters, the relative level of electromagnetic fields and the building restriction zones. The proposed model can be the basis of the physical modeling of the settlement's electromagnetic pollution monitoring system.
{"title":"CONCEPTUAL MODELING OF THE DATABASE OF GIS MONITORING OF ELECTROMAGNETIC POLLUTION OF SETTLEMENTS","authors":"V. Kozar, V. Bakhariev, N. Halchenko, Y. Dorozhko","doi":"10.18664/1994-7852.202.2022.273613","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273613","url":null,"abstract":"The article presents the results of conceptual modeling of the geospatial database for monitoring electromagnetic pollution of settlements. Recently, the world has seen a rapid increase in the number of sources and the level of electromagnetic radiation. This can negatively affect people's health and their environment. The analysis of the publications showed that today researchers have formed a theoretical base for assessing the impact of electromagnetic radiation on people and the environment, developed models of the propagation of electromagnetic waves, ways and methods of protection against their harmful effects. However, not enough attention has been paid to monitoring the electromagnetic pollution of settlements. Systematic measurements of electromagnetic field levels are carried out only by individual EU countries Systematic control of this type of pollution is not carried out in Ukraine, there are no regulatory documents regarding the procedure for its monitoring, but the maximum permissible levels of electromagnetic fields for the population are established. Data on the distribution of electromagnetic fields are interdisciplinary in nature and necessarily contain an indication of the location of objects. For their effective processing, it is advisable to use geo-information technologies. Based on the results of the analysis of the subject area of electromagnetic pollution monitoring, a conceptual data model was developed. It is described using UML tools. The model contains two sets of data. The basic set of geospatial data includes information about buildings of various purposes, land plots, streets, highways, railways, engineering communications, relief, soils, hydrography, territory zoning, facility addresses. The profile set includes data on electromagnetic radiation sources and their sanitary protection zones, control points, the results of calculations and measurements of radiation parameters, the relative level of electromagnetic fields and the building restriction zones. The proposed model can be the basis of the physical modeling of the settlement's electromagnetic pollution monitoring system. \u0000 ","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"243 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116288548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273622
O. A. Plakhtii, V. Nerubatskyi, D. Hordiienko, D. Shеlеst, A. Syniavskyi
The soft start device is designed to control the process of starting, operation and stopping of electric motors and enables smooth acceleration, smooth stopping, reduction of the starting current of the motor and coordination of the motor torque with the load moment. The article the control system of the triac device of the smooth start of an asynchronous motor with a constant load moment is considered. The control provides a reduction in the starting current and starting torque of the asynchronous motor. The principle of operation and the main technical parameters of the soft start device are described. The method of reducing power losses in power semiconductor elements of the soft start device is considered. The study of electromechanical processes in the soft start device when working with an asynchronous motor was carried out due to simulated computer modeling in the Matlab / Simulink software environment. The results of simulation modeling are given: oscillograms of input currents of the soft start device, dynamics of speed change and starting torque of an asynchronous motor. In the course of the simulation, it was established that the operation of the soft start device allows to reduce the starting current and starting torque by almost half. It is shown that the adjustment of the time to reach the full opening angle of the power switches of the soft start device and the starting angle of the opening of the power switches, which determines the acceleration dynamics of the asynchronous motor, significantly affects the value of the maximum amplitude value of the current and torque. The results of theoretical studies were implemented in a real physical prototype of the soft start device. The image of the boards of the developed soft start device is shown and its technical characteristics are indicated.
{"title":"OBTAINING DECORATIVE ALKALINE-ACTIVATED CEMENT BY USING SLAGS WITH A HIGH CONTENT OF IRON OXIDE","authors":"O. A. Plakhtii, V. Nerubatskyi, D. Hordiienko, D. Shеlеst, A. Syniavskyi","doi":"10.18664/1994-7852.202.2022.273622","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273622","url":null,"abstract":"The soft start device is designed to control the process of starting, operation and stopping of electric motors and enables smooth acceleration, smooth stopping, reduction of the starting current of the motor and coordination of the motor torque with the load moment. The article the control system of the triac device of the smooth start of an asynchronous motor with a constant load moment is considered. The control provides a reduction in the starting current and starting torque of the asynchronous motor. The principle of operation and the main technical parameters of the soft start device are described. The method of reducing power losses in power semiconductor elements of the soft start device is considered. The study of electromechanical processes in the soft start device when working with an asynchronous motor was carried out due to simulated computer modeling in the Matlab / Simulink software environment. The results of simulation modeling are given: oscillograms of input currents of the soft start device, dynamics of speed change and starting torque of an asynchronous motor. In the course of the simulation, it was established that the operation of the soft start device allows to reduce the starting current and starting torque by almost half. It is shown that the adjustment of the time to reach the full opening angle of the power switches of the soft start device and the starting angle of the opening of the power switches, which determines the acceleration dynamics of the asynchronous motor, significantly affects the value of the maximum amplitude value of the current and torque. The results of theoretical studies were implemented in a real physical prototype of the soft start device. The image of the boards of the developed soft start device is shown and its technical characteristics are indicated.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"437 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132657476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273496
I. Redko, Y. Burda, Y. Pivnenko, H. Bilovol, Yevgeny Moskalyov, Vadym Boyko
Methane, which is found in coal seams, has long been seen as an alternative to imported natural gas. Capturing that victorious methane can immediately increase the versatility of the production of footwear, increase the safety of the minds of the workforce, and change the negative impact to dovkillya. And yet, there are low technical and technological folds, which galmuyut the development of the type of bottle and utilization of methane.One of the main directions of extraction of coal mine methane is the generation of thermal energy in boiler houses and other heat generators. However, this type of paliva is unstable in concentration and important, due to the fact that the technical riven has the same characteristics. The current development of technology and technology, in general, allows you to successfully improve the nutrition of methane. There are very few data on environmental and energy indicators for the process of scalding with different palnikov outbuildings.In the coal mines of the Donbass, there is a widespread stagnation of the boiler room with bottom (hollow) toe shoes. Further indications of scalding with different design features of this type of stokers will help to improve nutrition by reducing the chemical insufficiency of scalding gas and increasing the thermal pressure of the boiler. It is shown that the computer simulation and re-verification of the efficiency of coal mine methane scorching in scorching boilers from the stoking of bottom (hollow) stokers is shown to be possible.In the robot, an experimental simulation of the process of burning coal methane in the bottom of the burners of a modernized design was carried out, and tests were carried out on the distribution of medium-mass parameters in the gas at the exit from the fire line from the vicarious grids. And also, an analysis of stationary watering of the average characteristics of the flow fluidity, temperature, concentration of components, nitrogen oxide and nitrogen oxide fluidity was carried out.
{"title":"NUMERICAL AND EXPERIMENTAL MODELING OF LOW-CALORIE GAS FUELS COMBUSTION PROCESSES","authors":"I. Redko, Y. Burda, Y. Pivnenko, H. Bilovol, Yevgeny Moskalyov, Vadym Boyko","doi":"10.18664/1994-7852.202.2022.273496","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273496","url":null,"abstract":"Methane, which is found in coal seams, has long been seen as an alternative to imported natural gas. Capturing that victorious methane can immediately increase the versatility of the production of footwear, increase the safety of the minds of the workforce, and change the negative impact to dovkillya. And yet, there are low technical and technological folds, which galmuyut the development of the type of bottle and utilization of methane.One of the main directions of extraction of coal mine methane is the generation of thermal energy in boiler houses and other heat generators. However, this type of paliva is unstable in concentration and important, due to the fact that the technical riven has the same characteristics. The current development of technology and technology, in general, allows you to successfully improve the nutrition of methane. There are very few data on environmental and energy indicators for the process of scalding with different palnikov outbuildings.In the coal mines of the Donbass, there is a widespread stagnation of the boiler room with bottom (hollow) toe shoes. Further indications of scalding with different design features of this type of stokers will help to improve nutrition by reducing the chemical insufficiency of scalding gas and increasing the thermal pressure of the boiler. It is shown that the computer simulation and re-verification of the efficiency of coal mine methane scorching in scorching boilers from the stoking of bottom (hollow) stokers is shown to be possible.In the robot, an experimental simulation of the process of burning coal methane in the bottom of the burners of a modernized design was carried out, and tests were carried out on the distribution of medium-mass parameters in the gas at the exit from the fire line from the vicarious grids. And also, an analysis of stationary watering of the average characteristics of the flow fluidity, temperature, concentration of components, nitrogen oxide and nitrogen oxide fluidity was carried out.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116900288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273568
Serhii Alforov
The article presents the results of an experimental study of the fuel-air flow inside a vortex furnace with a fluidized bed using a special air distribution nozzle. Nowadays, the issue of dependence on fossil energy resources is the most important problem for the countries of Europe. One of the promising solutions to this problem is the use of vortex solid fuel furnaces for burning low-calorie types of fuel, such as waste from the woodworking and agricultural industries. Our country has developed agricultural and woodworking sectors of the economy, so the amount of waste from these industries is significant, which allows them to be used to cover the energy needs of the state. At the same time, there is a significant number of solid fuel boilers on the territory of Ukraine that can be used for this task. The main difficulties in burning low-grade fuels in solid-fuel boilers are the low level of efficiency of these vortex furnaces and insufficient theoretical information about this. To conduct the experiment, a special installation in the form of a cylinder with a nozzle inside is used. The nozzle has a plate inclination of 15 °, which does not exceed 10% of the total live cross-sectional area of the chamber of the experimental setup. In the course of the experiment, the boundary conditions for the formation of a vortex flow at different amounts of fuel and different air flows were determined, and the values of pressure loss and flow velocity were shown. The results are presented in graphical and tabular form. For example, for 2.9 kg of sawdust, the maximum speed of vortex flow formation is 0.72 m/s, for 5.8 kg this value is 0.57 m/s. The obtained results make it possible to formulate recommendations for the improvement of existing solid fuel furnaces due to the use of special nozzles for the intensification of combustion processes. This creates prospects for the development of the country's energy sector. Keywords: fuel combustion, vortex furnaces, furnace aerodynamics, special nozzle.
{"title":"INVESTIGATION OF THE FUEL-AIR FLOW INSIDE A VORTEX FURNACE WITH A FLUIDIZED BED USING A SPECIAL AIR-DISTRIBUTING NOZZLE","authors":"Serhii Alforov","doi":"10.18664/1994-7852.202.2022.273568","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273568","url":null,"abstract":"The article presents the results of an experimental study of the fuel-air flow inside a vortex furnace with a fluidized bed using a special air distribution nozzle. Nowadays, the issue of dependence on fossil energy resources is the most important problem for the countries of Europe. One of the promising solutions to this problem is the use of vortex solid fuel furnaces for burning low-calorie types of fuel, such as waste from the woodworking and agricultural industries. Our country has developed agricultural and woodworking sectors of the economy, so the amount of waste from these industries is significant, which allows them to be used to cover the energy needs of the state. At the same time, there is a significant number of solid fuel boilers on the territory of Ukraine that can be used for this task. The main difficulties in burning low-grade fuels in solid-fuel boilers are the low level of efficiency of these vortex furnaces and insufficient theoretical information about this. To conduct the experiment, a special installation in the form of a cylinder with a nozzle inside is used. The nozzle has a plate inclination of 15 °, which does not exceed 10% of the total live cross-sectional area of the chamber of the experimental setup. In the course of the experiment, the boundary conditions for the formation of a vortex flow at different amounts of fuel and different air flows were determined, and the values of pressure loss and flow velocity were shown. The results are presented in graphical and tabular form. For example, for 2.9 kg of sawdust, the maximum speed of vortex flow formation is 0.72 m/s, for 5.8 kg this value is 0.57 m/s. The obtained results make it possible to formulate recommendations for the improvement of existing solid fuel furnaces due to the use of special nozzles for the intensification of combustion processes. This creates prospects for the development of the country's energy sector. Keywords: fuel combustion, vortex furnaces, furnace aerodynamics, special nozzle. ","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125603294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273633
O. Gubarevych
The efficiency of providing transportation is related to increasing the reliability of the transportation infrastructure. To ensure reliable and economical operation, it is necessary to develop systems of functional diagnostics of the main elements of vehicles, which provide continuous control of the technical condition of its main elements. Monitoring the state of asynchronous electric motors as part of electric drives of vehicles is an important modern issue, the solution of which depends on the reliability of the entire transport infrastructure. The most common type of damage in motors during operation is an inter-turn short circuit in the stator winding phase. Turn-to-turn closures are difficult to detect, but if they are present, the engine continues to operate with a change in its operating and electrodynamic indicators and characteristics. However, depending on the degree of turn-to-turn closures (the number of closed turns) in the winding phase, the probability and time of an emergency stop of the electric drive increase. In this paper, the influence of turn-to-turn closures of varying degrees on mechanical, electrical and energy parameters and engine characteristics under various operating modes has been studied. In the course of the research, a mathematical model of an induction motor was used with the established adequacy of the simulation results and the possibility of creating an asymmetric rotating stator field. The adopted simulation model of an induction motor with a squirrel-cage rotor is written in retarded coordinates. Also, studies were carried out on the effect of turn-to-turn closures on the ripple coefficient of the electromagnetic torque and the unbalance coefficient of the stator phase currents. Based on the data obtained, recommendations are given on choosing the most effective method of electric current for diagnosing interturn faults in assessing the technical condition and predicting the failure-free operation of an asynchronous electric motor for use as part of an electric motor under construction. - in diagnostic systems of cars.
{"title":"A COMPREHENSIVE STUDY OF THE INFLUENCE OF DAMAGES OF THE STATOR WINDING OF ASYNCHRONOUS MOTORS DURING OPERATION OF VEHICLES","authors":"O. Gubarevych","doi":"10.18664/1994-7852.202.2022.273633","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273633","url":null,"abstract":"The efficiency of providing transportation is related to increasing the reliability of the transportation infrastructure. To ensure reliable and economical operation, it is necessary to develop systems of functional diagnostics of the main elements of vehicles, which provide continuous control of the technical condition of its main elements. Monitoring the state of asynchronous electric motors as part of electric drives of vehicles is an important modern issue, the solution of which depends on the reliability of the entire transport infrastructure. The most common type of damage in motors during operation is an inter-turn short circuit in the stator winding phase. Turn-to-turn closures are difficult to detect, but if they are present, the engine continues to operate with a change in its operating and electrodynamic indicators and characteristics. However, depending on the degree of turn-to-turn closures (the number of closed turns) in the winding phase, the probability and time of an emergency stop of the electric drive increase. In this paper, the influence of turn-to-turn closures of varying degrees on mechanical, electrical and energy parameters and engine characteristics under various operating modes has been studied. In the course of the research, a mathematical model of an induction motor was used with the established adequacy of the simulation results and the possibility of creating an asymmetric rotating stator field. The adopted simulation model of an induction motor with a squirrel-cage rotor is written in retarded coordinates. Also, studies were carried out on the effect of turn-to-turn closures on the ripple coefficient of the electromagnetic torque and the unbalance coefficient of the stator phase currents. Based on the data obtained, recommendations are given on choosing the most effective method of electric current for diagnosing interturn faults in assessing the technical condition and predicting the failure-free operation of an asynchronous electric motor for use as part of an electric motor under construction. - in diagnostic systems of cars.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125304653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-22DOI: 10.18664/1994-7852.202.2022.273573
O. Synilo
Now, the issue of protecting the environment and reducing the use of fossil non-renewable energy sources is becoming increasingly important. For modern heating and air conditioning systems, it is imperative to reduce emissions of harmful substances, especially CO2. This can be realized by significantly reducing the use of fossil non-renewable fuels and reconstructing engineering systems to the current level of energy saving. The annual growth in demand for fossil fuels will be reduced through the optimization of substations and heat distribution devices, which is a necessary step for the development of the country's industry and economy. Therefore, today the main task is to increase the energy efficiency of the use of resources and increase the potential of alternative types of energy in combination with modern low-temperature energy-efficient heat distribution systems, one of which is radiant water panels. The advantages of radiant heating are the absence of dust transfer, since the convective process of mixing air masses is remote, does not require the connection of electrical power, it is possible to work with low-temperature sources of heat supply, no maintenance is required, since there are no fans, electric motors, bearings, lubricants, filters, etc. The main advantage can be distinguished from the use of additional equipment for destratification, as there is no overheating of the upper zones of the heated building. The article presents the results of improving the method of mounting beam-ceiling fixtures with respect to their orientation in space. The results of numerical calculations indicate the efficiency of mounting the equipment at an angle of 45 degrees, which increases the efficiency by 10 % in relation to the 0° orientation. By achieving this mounting and installation option, the required capacity of the heat supply source is reduced and the amount of energy resources used is reduced.
{"title":"IMPROVING THE EFFICIENCY OF USING WATER RADIANT HEATING SYSTEMS","authors":"O. Synilo","doi":"10.18664/1994-7852.202.2022.273573","DOIUrl":"https://doi.org/10.18664/1994-7852.202.2022.273573","url":null,"abstract":"Now, the issue of protecting the environment and reducing the use of fossil non-renewable energy sources is becoming increasingly important. For modern heating and air conditioning systems, it is imperative to reduce emissions of harmful substances, especially CO2. This can be realized by significantly reducing the use of fossil non-renewable fuels and reconstructing engineering systems to the current level of energy saving. The annual growth in demand for fossil fuels will be reduced through the optimization of substations and heat distribution devices, which is a necessary step for the development of the country's industry and economy. Therefore, today the main task is to increase the energy efficiency of the use of resources and increase the potential of alternative types of energy in combination with modern low-temperature energy-efficient heat distribution systems, one of which is radiant water panels. The advantages of radiant heating are the absence of dust transfer, since the convective process of mixing air masses is remote, does not require the connection of electrical power, it is possible to work with low-temperature sources of heat supply, no maintenance is required, since there are no fans, electric motors, bearings, lubricants, filters, etc. The main advantage can be distinguished from the use of additional equipment for destratification, as there is no overheating of the upper zones of the heated building. The article presents the results of improving the method of mounting beam-ceiling fixtures with respect to their orientation in space. The results of numerical calculations indicate the efficiency of mounting the equipment at an angle of 45 degrees, which increases the efficiency by 10 % in relation to the 0° orientation. By achieving this mounting and installation option, the required capacity of the heat supply source is reduced and the amount of energy resources used is reduced.","PeriodicalId":183715,"journal":{"name":"Collection of scientific works of the Ukrainian State University of Railway Transport","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115971777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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