Pub Date : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.08
Yurii Ulitenko, Maryna Minenok, I. Kravchenko
Aircraft capabilities determine the performance of the engine that powers it, and therefore, the creation of the latest high-speed aircraft is directly related to the development level of aircraft engine building. The main requirements for high-speed aircraft engines are an extended operating envelope in terms of speed and flight altitude. Specific thrust and specific impulse increase with each new generation of turbofan engines with afterburner, but the use of high technology leads to a significant increase in engine cost. Simultaneously, the design of existing engines has large reserves for modernization. The water injection system in the turbofan engine with afterburner is one of the available ways to improve the design. Such updated engines will theoretically meet the requirements of high-speed air-craft developers regarding thrust and other key parameters. Simultaneously, communication with the existing types of power plants will remain. This article considers the possibility of expanding the operating envelope and short-term forcing of the turbofan engine with afterburner of classical configuration to flight speeds equal to Mach number 3. This paper studied the effect of water injection at the high-pressure compressor inlet of the turbofan engine with afterburner on its performances. The authors present the results of calculations regarding the effect of water injection at the high-pressure compressor inlet of turbofan engine with afterburner on the parameters of working fluid along the engine duct. The application of the obtained results will improve the thermodynamic efficiency and expand the operating envelope of turbofans engines with afterburner using materials widely applicable in the production of aircraft gas turbine engines in our time, as well as reduce the period of creating competitive engines for high-speed aircraft due to targeted search their rational thermodynamic and constructive-geometric outline.
{"title":"Аналіз характеристик турбореактивного двоконтурного двигуна з форсажною камерою згоряння з впорскуванням води на вході до компресора високого тиску","authors":"Yurii Ulitenko, Maryna Minenok, I. Kravchenko","doi":"10.32620/aktt.2022.4sup1.08","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.08","url":null,"abstract":"Aircraft capabilities determine the performance of the engine that powers it, and therefore, the creation of the latest high-speed aircraft is directly related to the development level of aircraft engine building. The main requirements for high-speed aircraft engines are an extended operating envelope in terms of speed and flight altitude. Specific thrust and specific impulse increase with each new generation of turbofan engines with afterburner, but the use of high technology leads to a significant increase in engine cost. Simultaneously, the design of existing engines has large reserves for modernization. The water injection system in the turbofan engine with afterburner is one of the available ways to improve the design. Such updated engines will theoretically meet the requirements of high-speed air-craft developers regarding thrust and other key parameters. Simultaneously, communication with the existing types of power plants will remain. This article considers the possibility of expanding the operating envelope and short-term forcing of the turbofan engine with afterburner of classical configuration to flight speeds equal to Mach number 3. This paper studied the effect of water injection at the high-pressure compressor inlet of the turbofan engine with afterburner on its performances. The authors present the results of calculations regarding the effect of water injection at the high-pressure compressor inlet of turbofan engine with afterburner on the parameters of working fluid along the engine duct. The application of the obtained results will improve the thermodynamic efficiency and expand the operating envelope of turbofans engines with afterburner using materials widely applicable in the production of aircraft gas turbine engines in our time, as well as reduce the period of creating competitive engines for high-speed aircraft due to targeted search their rational thermodynamic and constructive-geometric outline.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114858542","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.19
O. Shorinov, Anatolii Dolmatov, Serhii Polyvianyi
The effect of temperature and air pressure at the supersonic nozzle inlet, as well as the distance from the nozzle outlet to the surface of the substrate (stand-of-distance) on the powder usage rate of nickel-based powder in low pressure cold gas-dynamic spraying (inlet pressure up to 1.0 MPa) was analyzed. One of the most important parameters characterizing the deposition efficiency of the spraying process is the powder usage rate. This parameter is the ratio of the mass of the coating to the mass of the powder used to obtain this one. For the process of cold gas-dynamic spraying, implemented on the equipment using air pressure up to 1.0 MPa, the main disadvantage is the relatively low-powder usage rate. To increase it (but not limited to it), a ceramic component, such as alumina Al2O3, is added to pure metal powders. In this study a nickel-based powder mixture, in which the content of Al2O3 powder is about 10% mass., was used. Titanium alloy plates BT9 were used as the substrate material. Based on the multifactor planning of the experiment, the effect of the complex parameters of the low-pressure cold gas-dynamic spraying on the powder usage rate was studied. After the coating deposition according to the matrix of the experiment, the samples with coatings were weighed. According to the known mass of the samples before spraying and the increase in their mass, the powder usage rate was calculated. From the analysis of the obtained statistical data, the dependence of the effect of the complex parameters of the deposition process on the powder usage rate was developed. The maximum value of the powder usage rate were obtained up to 35 %. It was confirmed that the air temperature at the nozzle inlet has the greatest effect on the above-mentioned parameter. The explanation of this is the increase in gas flow temperature and velocity, and as a result, the increase in the velocity and temperature of the powder particles in this flow. Higher values of the velocity and temperature of the particles lead to more intense plastic deformation of particles during impact with the substrate and their adhesion to it.
{"title":"Експериментальне дослідження впливу параметрів газодинамічного напилювання на коефіцієнт використання порошку","authors":"O. Shorinov, Anatolii Dolmatov, Serhii Polyvianyi","doi":"10.32620/aktt.2022.4sup2.19","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.19","url":null,"abstract":"The effect of temperature and air pressure at the supersonic nozzle inlet, as well as the distance from the nozzle outlet to the surface of the substrate (stand-of-distance) on the powder usage rate of nickel-based powder in low pressure cold gas-dynamic spraying (inlet pressure up to 1.0 MPa) was analyzed. One of the most important parameters characterizing the deposition efficiency of the spraying process is the powder usage rate. This parameter is the ratio of the mass of the coating to the mass of the powder used to obtain this one. For the process of cold gas-dynamic spraying, implemented on the equipment using air pressure up to 1.0 MPa, the main disadvantage is the relatively low-powder usage rate. To increase it (but not limited to it), a ceramic component, such as alumina Al2O3, is added to pure metal powders. In this study a nickel-based powder mixture, in which the content of Al2O3 powder is about 10% mass., was used. Titanium alloy plates BT9 were used as the substrate material. Based on the multifactor planning of the experiment, the effect of the complex parameters of the low-pressure cold gas-dynamic spraying on the powder usage rate was studied. After the coating deposition according to the matrix of the experiment, the samples with coatings were weighed. According to the known mass of the samples before spraying and the increase in their mass, the powder usage rate was calculated. From the analysis of the obtained statistical data, the dependence of the effect of the complex parameters of the deposition process on the powder usage rate was developed. The maximum value of the powder usage rate were obtained up to 35 %. It was confirmed that the air temperature at the nozzle inlet has the greatest effect on the above-mentioned parameter. The explanation of this is the increase in gas flow temperature and velocity, and as a result, the increase in the velocity and temperature of the powder particles in this flow. Higher values of the velocity and temperature of the particles lead to more intense plastic deformation of particles during impact with the substrate and their adhesion to it.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133864822","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.03
Vadym Nerubasskyi
The introductory part of the article provides information about the features of the modern Russian aircraft and engine designations, about the disappearance of the world famous brands such as "Tu", "Yak", "PS", "NK" and others. The tone of many publications testifies to a certain "megalomania" of the Russian aviation industry, whose real achievements of which are greatly exaggerated. One of the main prides of Russia is the PD-14 turbofan engine. This evaluation is the purpose of this article. The history of the development and testing of the PD-14 turbofan engine is given. Simultaneously, it is indicated that it was an alternative engine for the MS-21 aircraft, for which the Western PW-1000G engine was initially selected. Detailed information is given on the production and testing of experimental engines, including in a flying laboratory. It is noted that PD-14 is actually a program for the entire aircraft engine industry in Russia and other enterprises are actively involved in its implementation, in addition to the main subcontractors of the UEC - Aviadvigatel and Perm Motors. In the development of the PD-14, the experience of creating and fine-tuning the PS-90A2 turbofan engine was widely used. It is indicated that when creating the PD-14, many innovative and advanced technologies were developed and applied (16 key technologies). The developers of PD-14 pay considerable attention to the creation of an effective after-sales service system (a network of field offices, engine service stations, spare parts warehouses, ensuring the replacement of modules in operation, etc.), the absence of which previously prevented the successful marketing of Russian engines (a characteristic negative example is the SaM-146 engines of the SSJ regional airliner). General information about the development programs, the main technical characteristics and design features of the competitors of the PD-14 - western PW1000G and LEAP-1 turbofan engines are given. These engines are already widely used in several types of medium-haul aircraft. The PD-14 is compared with its main competitors in terms of many parameters and design characteristics. It is concluded that a modern 5th generation turbofan engine has been created in Russia, which has come close in terms of characteristics and the level of applied technologies to the existing serial Western engines of a similar thrust class. However, the future of the PD-14 engine in the current conditions of the fall of the Russian economy due to the war with Ukraine and EU and US sanctions looks uncertain.
{"title":"ПД-14 – чи такий вiн вдалий?","authors":"Vadym Nerubasskyi","doi":"10.32620/aktt.2022.4sup1.03","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.03","url":null,"abstract":"The introductory part of the article provides information about the features of the modern Russian aircraft and engine designations, about the disappearance of the world famous brands such as \"Tu\", \"Yak\", \"PS\", \"NK\" and others. The tone of many publications testifies to a certain \"megalomania\" of the Russian aviation industry, whose real achievements of which are greatly exaggerated. One of the main prides of Russia is the PD-14 turbofan engine. This evaluation is the purpose of this article. The history of the development and testing of the PD-14 turbofan engine is given. Simultaneously, it is indicated that it was an alternative engine for the MS-21 aircraft, for which the Western PW-1000G engine was initially selected. Detailed information is given on the production and testing of experimental engines, including in a flying laboratory. It is noted that PD-14 is actually a program for the entire aircraft engine industry in Russia and other enterprises are actively involved in its implementation, in addition to the main subcontractors of the UEC - Aviadvigatel and Perm Motors. In the development of the PD-14, the experience of creating and fine-tuning the PS-90A2 turbofan engine was widely used. It is indicated that when creating the PD-14, many innovative and advanced technologies were developed and applied (16 key technologies). The developers of PD-14 pay considerable attention to the creation of an effective after-sales service system (a network of field offices, engine service stations, spare parts warehouses, ensuring the replacement of modules in operation, etc.), the absence of which previously prevented the successful marketing of Russian engines (a characteristic negative example is the SaM-146 engines of the SSJ regional airliner). General information about the development programs, the main technical characteristics and design features of the competitors of the PD-14 - western PW1000G and LEAP-1 turbofan engines are given. These engines are already widely used in several types of medium-haul aircraft. The PD-14 is compared with its main competitors in terms of many parameters and design characteristics. It is concluded that a modern 5th generation turbofan engine has been created in Russia, which has come close in terms of characteristics and the level of applied technologies to the existing serial Western engines of a similar thrust class. However, the future of the PD-14 engine in the current conditions of the fall of the Russian economy due to the war with Ukraine and EU and US sanctions looks uncertain.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121738983","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.02
O. Denisyuk, Anton Balalaiev, Kateryna Balalaieva
The flow of gas in the flow path of a gas turbine engine (GTE) is accompanied by a rather complex phenomenon. These are a three-dimensional boundary layer, an incoming vortex, a paired vortex, flow turbulence, aerodynamic wakes behind the trailing edge, separation of the boundary layer from the blade surface, pressure pulsations, uneven and unsteady flow, secondary overflows, changes in the angles of flow exit, etc. Flow R&D of a GTE remains a rather complex process, and requires the use of reliable research methods and techniques. Nowadays, two known methods are used to study a gas flow through the flow path of a GTE ˗ experimental and calculated. Calculated, in turn, can be divided into analytical and numerical. An important stage of the numerical experiment is the solution to test problems for the possibility of setting the parameters of the numerical experiment. In this work, two test tasks were carried out. The object of the research was two compressor cascades, consisting of the identical airfoils series KR-33. The profile chord was 52 mm; the pitch cascade was 52 mm. The difference was in the installation angle of these profiles: variant 1 of the compressor cascade has an installation angle of 63.5º; variant 2 of the compressor cascade has an installation angle of 89.5º. A computational domain was constructed for each compressor cascades of airfoils and consisted of 5 million cells. Air under normal atmospheric conditions was chosen as the working fluid. The flow regime of compressor cascades varied in the range of coefficient λ = 0.26…0.9 and λ = 0.265…0.8, where the coefficient λ is the reduced velocity. The unstructured mesh method with an adaptation for the boundary layer was chosen to construct the computational mesh. Such a combination makes it possible to correctly model the flow in the boundary layer near the walls. The turbulence model SST was taken to close the Navier-Stokes equations. A comparison of the results of numerical and physical experiments for two variants of compressor cascades shows that the flow simulation error is less than 5%. Because of the calculation, the choice of this turbulence model for subsequent studies of the flow in the stages of the compressor, fan, and propfan will be justified.
{"title":"Test problem of the flow modeling in axial compressor cascades","authors":"O. Denisyuk, Anton Balalaiev, Kateryna Balalaieva","doi":"10.32620/aktt.2022.4sup2.02","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.02","url":null,"abstract":"The flow of gas in the flow path of a gas turbine engine (GTE) is accompanied by a rather complex phenomenon. These are a three-dimensional boundary layer, an incoming vortex, a paired vortex, flow turbulence, aerodynamic wakes behind the trailing edge, separation of the boundary layer from the blade surface, pressure pulsations, uneven and unsteady flow, secondary overflows, changes in the angles of flow exit, etc. Flow R&D of a GTE remains a rather complex process, and requires the use of reliable research methods and techniques. Nowadays, two known methods are used to study a gas flow through the flow path of a GTE ˗ experimental and calculated. Calculated, in turn, can be divided into analytical and numerical. An important stage of the numerical experiment is the solution to test problems for the possibility of setting the parameters of the numerical experiment. In this work, two test tasks were carried out. The object of the research was two compressor cascades, consisting of the identical airfoils series KR-33. The profile chord was 52 mm; the pitch cascade was 52 mm. The difference was in the installation angle of these profiles: variant 1 of the compressor cascade has an installation angle of 63.5º; variant 2 of the compressor cascade has an installation angle of 89.5º. A computational domain was constructed for each compressor cascades of airfoils and consisted of 5 million cells. Air under normal atmospheric conditions was chosen as the working fluid. The flow regime of compressor cascades varied in the range of coefficient λ = 0.26…0.9 and λ = 0.265…0.8, where the coefficient λ is the reduced velocity. The unstructured mesh method with an adaptation for the boundary layer was chosen to construct the computational mesh. Such a combination makes it possible to correctly model the flow in the boundary layer near the walls. The turbulence model SST was taken to close the Navier-Stokes equations. A comparison of the results of numerical and physical experiments for two variants of compressor cascades shows that the flow simulation error is less than 5%. Because of the calculation, the choice of this turbulence model for subsequent studies of the flow in the stages of the compressor, fan, and propfan will be justified.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127662378","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup2.08
M. Tkach, S. Kulishov, V. Polischuk, Yurii Halynkin, A. Proskurin, Vladimir Kluchnyk
A description of the stand based on a digital speckle interferometer with a diffuse reference wave and separated branches is given, which allows determining the natural frequencies and vibration modes of objects in real time. In the frequency range 100...4000 Hz, an experimental study of the vibration characteristics of a turbine rotor blade of a gas turbine engine was carried out, with rigid fastening of the blade fir tree part, which was achieved by fixing the blade in the lock and then fixing it in the clamping device. In the frequency range from 100 to 4000 Hz, 9 blade vibration modes were identified. The object of the study is the turbine rotor blade of a gas turbine engine with a height along the trailing edge of 288 mm and a chord in the middle section of 88.5 mm. A solid-state geometric model of a rotor blade based on a faceted body obtained from 3D scanning has been created. Concerning the frequency range 100...4000 Hz, using the ANSYS Workbench software package, a series of calculations of the resonant frequencies of the blade by the finite element method was carried out. Many vibration modes have been obtained, and the data obtained from experiments and calculations have been compared. The analysis of the spectrum of the natural vibration frequencies of the blade showed that the root-mean-square value of the deviations between the results obtained is 5.5% for the same modes. To verify the software calculation, the values of the resonance frequencies were recalculated using a three-dimensional model of the blade fixed in the lock. To determine the influence of the boundary conditions for fixing a gas turbine blade on its vibration characteristics, a series of calculations of the resonance frequencies and vibration modes of the blade model with cutting off a part of the blade at different heights was carried out. It is shown that cutting off the fir tree part of the blade root when modeling the boundary conditions of fixing makes it possible to simplify the calculation process by simplifying the geometry of the three-dimensional model of the blade under study, with a minimum loss of calculation accuracy.
{"title":"A method for determining the characteristics of the steady creep of a single crystal alloy","authors":"M. Tkach, S. Kulishov, V. Polischuk, Yurii Halynkin, A. Proskurin, Vladimir Kluchnyk","doi":"10.32620/aktt.2022.4sup2.08","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.08","url":null,"abstract":"A description of the stand based on a digital speckle interferometer with a diffuse reference wave and separated branches is given, which allows determining the natural frequencies and vibration modes of objects in real time. In the frequency range 100...4000 Hz, an experimental study of the vibration characteristics of a turbine rotor blade of a gas turbine engine was carried out, with rigid fastening of the blade fir tree part, which was achieved by fixing the blade in the lock and then fixing it in the clamping device. In the frequency range from 100 to 4000 Hz, 9 blade vibration modes were identified. The object of the study is the turbine rotor blade of a gas turbine engine with a height along the trailing edge of 288 mm and a chord in the middle section of 88.5 mm. A solid-state geometric model of a rotor blade based on a faceted body obtained from 3D scanning has been created. Concerning the frequency range 100...4000 Hz, using the ANSYS Workbench software package, a series of calculations of the resonant frequencies of the blade by the finite element method was carried out. Many vibration modes have been obtained, and the data obtained from experiments and calculations have been compared. The analysis of the spectrum of the natural vibration frequencies of the blade showed that the root-mean-square value of the deviations between the results obtained is 5.5% for the same modes. To verify the software calculation, the values of the resonance frequencies were recalculated using a three-dimensional model of the blade fixed in the lock. To determine the influence of the boundary conditions for fixing a gas turbine blade on its vibration characteristics, a series of calculations of the resonance frequencies and vibration modes of the blade model with cutting off a part of the blade at different heights was carried out. It is shown that cutting off the fir tree part of the blade root when modeling the boundary conditions of fixing makes it possible to simplify the calculation process by simplifying the geometry of the three-dimensional model of the blade under study, with a minimum loss of calculation accuracy.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123610866","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.12
V. Korobko, Anatoliy Shevtsov
A distinguishing feature of these days is the general tendency to decrease the temperature level of the waste heat of engines for power plants in industry, transport, and energy. These circumstances complicate the usage of traditional energy-saving technologies designed to transform this heat into mechanical work. Given the lack of effective technologies, large volumes of such heat emissions are lost. As an example, we can consider ship power engineering. On ships that are equipped with dual-fuel medium and low-speed engines, the thermal emissions of the cooling systems have a temperature of 355…365 K. Given the small exegetical potential, the use of such low-temperature waste energy sources by any heat engines is a difficult problem. Therefore, the task of improving existing energy-saving technologies or developing new ones remains relevant. Thermoacoustic technologies can be useful in solving this problem. A significant advantage of thermoacoustic heat machines is the ability to use any external heat source, in this case low-temperature sources, and produce mechanical work. There are known cases of thermoacoustic oscillations at small temperature differences between heat sources under conditions of high humidity of the working environment. This phenomenon can be used to create low-temperature energy-saving systems based on thermoacoustic engines (TAE) with a wet two-phase working environment. The practical use of thermoacoustic systems as part of ship power plants requires additional research to solve low-level issues, in particular, increasing the specific power of the TAE. This work provides a description of the experimental equipment, design of experimental TAE with a wet working body and research methods. The results of the experiments showed that in experimental TAEs with a two-component (moist) working environment, the temperature of spontaneous thermoacoustic oscillations was 355…359 K, while the longitudinal temperature gradient in the matrix was 1.19…1.30 K/m. The specific power of TAE with a moist environment increased by 1.7…7 times, and the acoustic pressure increased by 2…4.7 times compared to the operation in dry air. It is shown that in the existing TAEs, the condensation of water vapor in the ceramic matrix and on the surfaces of the heat exchangers can lead to a loss of power, roughly up to 25 %, while maintaining the operational capacity.
{"title":"Експериментальні дослідження термоакустичних двигунів з двофазним робочим тілом","authors":"V. Korobko, Anatoliy Shevtsov","doi":"10.32620/aktt.2022.4sup1.12","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.12","url":null,"abstract":"A distinguishing feature of these days is the general tendency to decrease the temperature level of the waste heat of engines for power plants in industry, transport, and energy. These circumstances complicate the usage of traditional energy-saving technologies designed to transform this heat into mechanical work. Given the lack of effective technologies, large volumes of such heat emissions are lost. As an example, we can consider ship power engineering. On ships that are equipped with dual-fuel medium and low-speed engines, the thermal emissions of the cooling systems have a temperature of 355…365 K. Given the small exegetical potential, the use of such low-temperature waste energy sources by any heat engines is a difficult problem. Therefore, the task of improving existing energy-saving technologies or developing new ones remains relevant. Thermoacoustic technologies can be useful in solving this problem. A significant advantage of thermoacoustic heat machines is the ability to use any external heat source, in this case low-temperature sources, and produce mechanical work. There are known cases of thermoacoustic oscillations at small temperature differences between heat sources under conditions of high humidity of the working environment. This phenomenon can be used to create low-temperature energy-saving systems based on thermoacoustic engines (TAE) with a wet two-phase working environment. The practical use of thermoacoustic systems as part of ship power plants requires additional research to solve low-level issues, in particular, increasing the specific power of the TAE. This work provides a description of the experimental equipment, design of experimental TAE with a wet working body and research methods. The results of the experiments showed that in experimental TAEs with a two-component (moist) working environment, the temperature of spontaneous thermoacoustic oscillations was 355…359 K, while the longitudinal temperature gradient in the matrix was 1.19…1.30 K/m. The specific power of TAE with a moist environment increased by 1.7…7 times, and the acoustic pressure increased by 2…4.7 times compared to the operation in dry air. It is shown that in the existing TAEs, the condensation of water vapor in the ceramic matrix and on the surfaces of the heat exchangers can lead to a loss of power, roughly up to 25 %, while maintaining the operational capacity.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129021867","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.10
Serhii Yevsieiev
This paper presents the results of a numerical simulation of the gas flow in the flame tube of an annular combustion chamber of a gas turbine engine. Numerical simulation was performed in the ANSYS Fluent 2022 R1 computational complex, in which the numerical solution of the Reynolds-averaged Navier-Stokes equations (RANS) was implemented, the dissipation rates were determined using the Enhanced Wall Treatment near-wall function. For numerical simulation problems, a computational polyhedral mesh was built. The purpose of the calculations was to evaluate the effect of the method for supplying igniter hot gases to the start of the combustion chamber. The article does not address the operation of the igniter itself (its ignition, combustion, and the flow in it), but only its main task is the generation of a flame (gas) with a given temperature. All calculations were carried out for two gas temperatures, 800 and 1200 °C, at the outlet of the igniter nozzle, and a temperature of minus 20 °C at the inlet to the combustion chamber. In the calculation model, at the inlet to the igniter nozzle, the gas flow rate was set with a temperature taken from the experiment. When the chamber operates in the region of low temperatures, low velocities and pressures at the inlet, the degree of fuel evaporation and the mixing of its vapors with air have a significant effect. Therefore, with an increase in air flow through the chamber, the limits of flame blow-off expand. With a further increase in air flow, the processes of fuel evaporation and its burnout in the reverse current zone are completed, and flameout is mainly determined only by the temperature in the reverse current zone, and the boundaries of stable combustion narrow with increasing flow rate, which is typical for combusting a homogeneous mixture. The calculations found that the penetration and spread of heat when using igniter nozzles with a large diameter (12 mm) in the outlet section are higher than those in holes with a smaller diameter (8 mm). In the variants where the supply of hot gases is in the plane of the nozzle, a better distribution of heat in the zone of reverse currents is shown than where the supply of hot gases is carried out between the nozzles. Also, to analyze the results of the calculation, a criterion was proposed that shows the optimal conditions for the ignition of the mixture.
{"title":"Аналіз впливу способу подачі гарячих газів пристрою запалювача на запуск камери згоряння за допомогою тривимірного комп'ютерного моделювання","authors":"Serhii Yevsieiev","doi":"10.32620/aktt.2022.4sup1.10","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.10","url":null,"abstract":"This paper presents the results of a numerical simulation of the gas flow in the flame tube of an annular combustion chamber of a gas turbine engine. Numerical simulation was performed in the ANSYS Fluent 2022 R1 computational complex, in which the numerical solution of the Reynolds-averaged Navier-Stokes equations (RANS) was implemented, the dissipation rates were determined using the Enhanced Wall Treatment near-wall function. For numerical simulation problems, a computational polyhedral mesh was built. The purpose of the calculations was to evaluate the effect of the method for supplying igniter hot gases to the start of the combustion chamber. The article does not address the operation of the igniter itself (its ignition, combustion, and the flow in it), but only its main task is the generation of a flame (gas) with a given temperature. All calculations were carried out for two gas temperatures, 800 and 1200 °C, at the outlet of the igniter nozzle, and a temperature of minus 20 °C at the inlet to the combustion chamber. In the calculation model, at the inlet to the igniter nozzle, the gas flow rate was set with a temperature taken from the experiment. When the chamber operates in the region of low temperatures, low velocities and pressures at the inlet, the degree of fuel evaporation and the mixing of its vapors with air have a significant effect. Therefore, with an increase in air flow through the chamber, the limits of flame blow-off expand. With a further increase in air flow, the processes of fuel evaporation and its burnout in the reverse current zone are completed, and flameout is mainly determined only by the temperature in the reverse current zone, and the boundaries of stable combustion narrow with increasing flow rate, which is typical for combusting a homogeneous mixture. The calculations found that the penetration and spread of heat when using igniter nozzles with a large diameter (12 mm) in the outlet section are higher than those in holes with a smaller diameter (8 mm). In the variants where the supply of hot gases is in the plane of the nozzle, a better distribution of heat in the zone of reverse currents is shown than where the supply of hot gases is carried out between the nozzles. Also, to analyze the results of the calculation, a criterion was proposed that shows the optimal conditions for the ignition of the mixture.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115157786","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.04
Iryna Morozova, Yuriy Tereshchenko, Vasyl Yehunko
This paper considers the possibilities of improving the reliability and efficiency of the aircraft engine, which are one of the main indicators of quality and require high-quality fuel. Modern gas turbine engines (GTE) are much more powerful and economical compared with those produced 50 years ago. Nevertheless, manufacturers are constantly working to improve gas turbine engines with the main emphasis on their fuel efficiency. Mechanical impurities present in the fuel can clog the fuel filters, thereby cutting off the fuel supply. The presence of resins in the fuel leads to the formation of various deposits on engine parts, and the content of sulfur, acids and alkalis increases the corrosiveness of the fuel. The completeness of combustion and the tendency of carbon formation are the main performance characteristics of hydrocarbon fuels, which are of great practical importance in improving the efficiency and service life of the engine. Currently, there are many options for improving technical and economic indicators. The proposed ways to prepare a better fuel mixture before supplying it to the engine. The preparation of aviation fuel is carried out because of the electrophysical effects on the fuel. The electrophysical effect on the fuel is determined by a magnetic installation with a sign-changing magnetic field. Studies were conducted to determine the effect of electrophysical impact on the completeness of combustion of aviation fuel and carbon formation in the combustion chamber of a gas turbine engine. The method allows to give a comparative assessment of the completeness of combustion and carbon formation of fuels for engines with a small amount of fuel consumed for testing. It has been established that under electrophysical action on aviation fuel, the fuel combustion efficiency increases by 10...12 %, carbon formation in the gas turbine engine combustion chamber decreases by 20...25 %. The positive effect on the combustion process in the previous phases decreases the afterburning phase, therefore, a decrease in the temperature of the exhaust gases, a decrease in the concentration of nitrogen oxide by 12...16 %, carbon monoxide by 0.64...0.7 % and hydrocarbon by 25...35 %. After the electrophysical impact and the fuel running time, the content of resinous compounds increased four times, the content of oxygen compounds decreased by ~23 %, and the content of sulfur compounds decreased by ~25 %.
{"title":"Оцінка впливу експлуатаційних параметрів на роботу авіаційного газотурбінного двигуна","authors":"Iryna Morozova, Yuriy Tereshchenko, Vasyl Yehunko","doi":"10.32620/aktt.2022.4sup1.04","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.04","url":null,"abstract":"This paper considers the possibilities of improving the reliability and efficiency of the aircraft engine, which are one of the main indicators of quality and require high-quality fuel. Modern gas turbine engines (GTE) are much more powerful and economical compared with those produced 50 years ago. Nevertheless, manufacturers are constantly working to improve gas turbine engines with the main emphasis on their fuel efficiency. Mechanical impurities present in the fuel can clog the fuel filters, thereby cutting off the fuel supply. The presence of resins in the fuel leads to the formation of various deposits on engine parts, and the content of sulfur, acids and alkalis increases the corrosiveness of the fuel. The completeness of combustion and the tendency of carbon formation are the main performance characteristics of hydrocarbon fuels, which are of great practical importance in improving the efficiency and service life of the engine. Currently, there are many options for improving technical and economic indicators. The proposed ways to prepare a better fuel mixture before supplying it to the engine. The preparation of aviation fuel is carried out because of the electrophysical effects on the fuel. The electrophysical effect on the fuel is determined by a magnetic installation with a sign-changing magnetic field. Studies were conducted to determine the effect of electrophysical impact on the completeness of combustion of aviation fuel and carbon formation in the combustion chamber of a gas turbine engine. The method allows to give a comparative assessment of the completeness of combustion and carbon formation of fuels for engines with a small amount of fuel consumed for testing. It has been established that under electrophysical action on aviation fuel, the fuel combustion efficiency increases by 10...12 %, carbon formation in the gas turbine engine combustion chamber decreases by 20...25 %. The positive effect on the combustion process in the previous phases decreases the afterburning phase, therefore, a decrease in the temperature of the exhaust gases, a decrease in the concentration of nitrogen oxide by 12...16 %, carbon monoxide by 0.64...0.7 % and hydrocarbon by 25...35 %. After the electrophysical impact and the fuel running time, the content of resinous compounds increased four times, the content of oxygen compounds decreased by ~23 %, and the content of sulfur compounds decreased by ~25 %.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122648942","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}
In the process of developing a method for numerically investigating a plane flow around a nozzle array with a rotary diaphragm, calculations were performed for various degrees of opening of the rotary diaphragm δ and pressure drops π on the array. The article presents some results of a numerical study of the flow in the nozzle channel at the degree of opening of the rotary diaphragm δ = (1…0.15). Modeling and calculations of the flow of the working fluid were performed using the Fluent software package. The construction of computational areas, limited by one inter-blade channel, for a different degree of opening of the diaphragm of the nozzle apparatus has been carried out. The grids for the computational domains were constructed. Calculations were carried out for δ = (1…0.15) and for various degrees of pressure drop across the grate. Because of the performed calculations, flow patterns in the interblade channel and behind it, and the distribution of kinetic energy loss coefficients along the grating front at various degrees of aperture opening at the nozzle inlet, were obtained. Based on the results of the work carried out, the following conclusions can be drawn: the operation of a nozzle array with a rotary diaphragm at different degrees of opening of the rotary diaphragm δ and pressure drops π on the grate can be divided in the range of opening steps δ = (1…0.77) as operation in the nozzle mode, and in the range δ = (0.77…0.15) as in throttle mode; when the angle of attack changes, the values of the kinetic energy loss coefficients increase significantly (up to 25 %) only for π = 0.7 and δ = 1; at π = 0.3 and δ = 1, the coefficient increases slightly (up to 0.5 %); at π = 0.7; 0.3 and δ = 0.3, the coefficient increases to 5 %, while the coefficient ζі changes less relative to the coefficient ζ90 at the calculated angle of attack α0 = 90 grids). The results obtained in this work will be used to develop a technique for numerically investigating the spatial flow around nozzle arrays with rotary diaphragms.
{"title":"Процес дроселювання в соплових апаратах з поворотними діафрагмами","authors":"Оleksandr Zhyrkov, Оleksandr Usaty, Olena Avdieieva, Yuriy Torba","doi":"10.32620/aktt.2022.4sup2.03","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup2.03","url":null,"abstract":"In the process of developing a method for numerically investigating a plane flow around a nozzle array with a rotary diaphragm, calculations were performed for various degrees of opening of the rotary diaphragm δ and pressure drops π on the array. The article presents some results of a numerical study of the flow in the nozzle channel at the degree of opening of the rotary diaphragm δ = (1…0.15). Modeling and calculations of the flow of the working fluid were performed using the Fluent software package. The construction of computational areas, limited by one inter-blade channel, for a different degree of opening of the diaphragm of the nozzle apparatus has been carried out. The grids for the computational domains were constructed. Calculations were carried out for δ = (1…0.15) and for various degrees of pressure drop across the grate. Because of the performed calculations, flow patterns in the interblade channel and behind it, and the distribution of kinetic energy loss coefficients along the grating front at various degrees of aperture opening at the nozzle inlet, were obtained. Based on the results of the work carried out, the following conclusions can be drawn: the operation of a nozzle array with a rotary diaphragm at different degrees of opening of the rotary diaphragm δ and pressure drops π on the grate can be divided in the range of opening steps δ = (1…0.77) as operation in the nozzle mode, and in the range δ = (0.77…0.15) as in throttle mode; when the angle of attack changes, the values of the kinetic energy loss coefficients increase significantly (up to 25 %) only for π = 0.7 and δ = 1; at π = 0.3 and δ = 1, the coefficient increases slightly (up to 0.5 %); at π = 0.7; 0.3 and δ = 0.3, the coefficient increases to 5 %, while the coefficient ζі changes less relative to the coefficient ζ90 at the calculated angle of attack α0 = 90 grids). The results obtained in this work will be used to develop a technique for numerically investigating the spatial flow around nozzle arrays with rotary diaphragms.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126995663","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 : 2022-08-22DOI: 10.32620/aktt.2022.4sup1.05
Roman Maiboroda
The design of modern aircraft engines cannot be imagined without numerical simulation methods. The advantages of numerical simulation at the first stages of creating engines are obvious: the ability to explore different geometric models in a fairly short time, while the accuracy of calculations reaches 5 ... 15%. An integral part of the numerical experiment is conducting test problems, because of which it is necessary to identify the necessary topology of the computational grid and the turbulent viscosity model. The current study conducts a test problem of flow simulation in a supersonic compressor cascade-based on the STFF rotor to select the topology of the computational grid and the turbulent viscosity model for closing the system of Navier-Stokes equations. In this work, four variants of the computational grid and four models of turbulent viscosity were studied. The time step was automatically changed. The maximum time over time was 0.00005…0.001 s. Control points were set in front of the grating and behind it, where the value of the Mach number was displayed. When calculating, the value of the Mach number in front of the grating was selected by changing the value of the velocity at the input. The calculation was terminated when the values of the Mach numbers at the input and output of the cascade were reached, as well as constant values of the residuals, which did not change during subsequent iterations. 4 variants of the structured type computational grid were built. Grid No. 3 was chosen for further calculations since it provides sufficient similarity with the test results, and it also has a smaller size, which makes it possible to speed up the calculation. Next, calculations are performed for different types of turbulence models. The turbulence models SST, SST GTT, k-ω and RNG k-ε were considered. For all turbulence models, the boundary layer height was chosen based on the condition Y+ < 1. An analysis of the calculation results showed that the smallest error was obtained in calculations with the SST GTT turbulence model. This paper presents a comparison of the density distribution in the cross-section of the cascade with a schlieren photograph obtained from a field experiment. A qualitative analysis of the obtained results shows that the flow patterns around the STFF-based compressor grate are of a similar nature, in particular, in the interblade channel and edge wakes behind the cascade. Thus, for further research to study the flow in the fan, the topology of the Mesh3 computational grid and the turbulent viscosity model SST GTT were chosen.
{"title":"Моделювання течії в надзвуковій компресорній решітці","authors":"Roman Maiboroda","doi":"10.32620/aktt.2022.4sup1.05","DOIUrl":"https://doi.org/10.32620/aktt.2022.4sup1.05","url":null,"abstract":"The design of modern aircraft engines cannot be imagined without numerical simulation methods. The advantages of numerical simulation at the first stages of creating engines are obvious: the ability to explore different geometric models in a fairly short time, while the accuracy of calculations reaches 5 ... 15%. An integral part of the numerical experiment is conducting test problems, because of which it is necessary to identify the necessary topology of the computational grid and the turbulent viscosity model. The current study conducts a test problem of flow simulation in a supersonic compressor cascade-based on the STFF rotor to select the topology of the computational grid and the turbulent viscosity model for closing the system of Navier-Stokes equations. In this work, four variants of the computational grid and four models of turbulent viscosity were studied. The time step was automatically changed. The maximum time over time was 0.00005…0.001 s. Control points were set in front of the grating and behind it, where the value of the Mach number was displayed. When calculating, the value of the Mach number in front of the grating was selected by changing the value of the velocity at the input. The calculation was terminated when the values of the Mach numbers at the input and output of the cascade were reached, as well as constant values of the residuals, which did not change during subsequent iterations. 4 variants of the structured type computational grid were built. Grid No. 3 was chosen for further calculations since it provides sufficient similarity with the test results, and it also has a smaller size, which makes it possible to speed up the calculation. Next, calculations are performed for different types of turbulence models. The turbulence models SST, SST GTT, k-ω and RNG k-ε were considered. For all turbulence models, the boundary layer height was chosen based on the condition Y+ < 1. An analysis of the calculation results showed that the smallest error was obtained in calculations with the SST GTT turbulence model. This paper presents a comparison of the density distribution in the cross-section of the cascade with a schlieren photograph obtained from a field experiment. A qualitative analysis of the obtained results shows that the flow patterns around the STFF-based compressor grate are of a similar nature, in particular, in the interblade channel and edge wakes behind the cascade. Thus, for further research to study the flow in the fan, the topology of the Mesh3 computational grid and the turbulent viscosity model SST GTT were chosen.","PeriodicalId":418062,"journal":{"name":"Aerospace technic and technology","volume":"247 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114277528","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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