{"title":"CHARACTERISTICS OF FUEL DISTRIBUTION IN THE VOLUME OF THE COMBUSTION CHAMBER OF TWO-STROKE DIESEL ENGINE WITH OPPOSITE MOVEMENT OF PISTONS","authors":"A. Lal, M. Shelestov","doi":"10.20998/0419-8719.2022.2.07","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.07","url":null,"abstract":"The paper analyzes ways of organizing mixture formation in a two-stroke diesel engine with reciprocating piston move-ment. Issues such as heat exchange with the walls, atomization and evaporation of fuel, distribution of the fuel jet and fuel vapors in the volume of the combustion chamber are considered. It is noted that the tangential vortex, which is achieved thanks to the special profiling of the windows, has a significant impact on the processes in the two-stroke diesel cylinder. The movement of the air charge is an important and critical factor in the formation of a mixture, the intensity of the vortex is estimated by the vortex number, which is the ratio of the number of revolutions of the vortex to the engine speed. In the process of volumetric mixture formation, the basic issues are fuel atomization and uniform distribution in the air volume. Fuel spraying has such criteria as the degree of dispersion and uniformity of the ignited fuel. The degree of dispersion is estimated by the average diameter of drops in the sprayed fuel. And the uniformity of spraying in the volume of the combustion chamber depends on the fuel jet shape, range of the jet, swirling air, the type of combustion chamber. The presence of long-range jets must necessarily be accompanied by the necessary intensity of air charge movement along the wall. Otherwise, in the conditions of the hot wall, which is typical for the domestic 6ChN12/2×12, in the places of contact of the jets with the overheated wall, significant solid deposits of soot are found, and these deposits have the character of coke, obtained as a result of fuel cracking. The mentioned drawback cannot be eliminated only by changing the wall temperature, if its main cause is not eliminated simultaneously, namely, a local lack of air (for example, in the central part of the piston bottom). Development of measures for prevention of this phenomenon will improve the engine's environmental friendliness and efficiency.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88299058","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}
A. Polyvianchuk, V.L. Khreshchenetskyi, O.P. Antonuk, M.V. Mitko, A. Dmitrieva
{"title":"IMPROVING THE ACCURACY OF SYSTEMS FOR GRAVIMETRIC CONTROL OF PARTICULATE MATTER IN EXHAUST GASES OF TRANSPORT DIESEL ENGINES","authors":"A. Polyvianchuk, V.L. Khreshchenetskyi, O.P. Antonuk, M.V. Mitko, A. Dmitrieva","doi":"10.20998/0419-8719.2022.2.08","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.08","url":null,"abstract":"The requirements of regulatory documents - UNECE Regulations R-49, R-96, international standard ISO 8178, etc. were analyzed regarding the technical characteristics and conditions of use of reference full-flow and alternative partial-flow systems (tunnels) for diluting the exhaust gases of transport diesel engines with air and carrying out gravimetric control of the content of solid particles in them. The world and domestic experience of operating dilution tunnels of various types - full-flow with 1st and 2nd dilution lines and partial-flow mini- and micro-tunnels and partial-flow mini- and micro-tunnels were studied, which made it possible to establish empirical dependencies for evaluating the degree of influence of the temperature regimes of gas sampling on the accuracy of measurements of mass emissions particulate matter in different modes of diesel operation. Mathematical models have been developed to determine the sample temperatures of diluted exhaust gases in tunnels of various types and to estimate the resulting measurement error of the normalized average operational emission of diesel particulate matter - the PM indicator. Based on the results of environmental tests of transport diesel engines 1Ch12/14 and 4ChN12/14 according to the 13-step ESC test cycle and developed mathematical models, calculation studies were carried out to assess the effect on the accuracy of a mini-tunnel with a diameter of 10 cm and a micro-tunnel with a diameter of 3 cm of the sampling temperature regimes, which were compared with a reference tunnel with a diameter of 46 cm. The research results proved the expediency of adjusting the temperature of the sample in the micro-tunnel to increase its accuracy by eliminating the significant methodical errors of measuring the PM indicator, which amount to -1.6 ... -1.7%. It was established that in the mini-tunnel the corresponding errors are not significant and amount to -0.3 ... -0.4%, which indicates that there is no need to adjust the temperature of the sample in this system.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84864197","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}
{"title":"RESEARCH OF A HIGH-EFFICIENCY CHARGE AIR COOLER","authors":"A. Savchenko, M. Shelestov","doi":"10.20998/0419-8719.2022.2.06","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.06","url":null,"abstract":"Currently, internal combustion engines have become widespread as sources of mechanical energy in many areas of human activity. It is the internal combustion engines that were and remain the most widespread in transport, where, as a rule, strict requirements are put forward for the mass-dimensional characteristics of the engines and the power plant as a whole. In order to meet these requirements, there is a constant increase in the level of forcing of the engines. For diesel engines, the most common technical measure that provides an increase in the level of engine forcing with almost unchanged weight and dimensional characteristics is an increase in supercharging pressure. However, as a result of air compression, its temperature increases, which is proportional to the degree of increase in air pressure in the compressor. An increase in air temperature causes a decrease in the mass charge of the cylinders, and therefore, a significant deterioration in the fuel combustion process. It also causes an increase in the level of maximum temperatures of the cycle, which in turn causes an increase in thermal loads and the rate of formation of nitrogen oxides in diesel cylinders. The above determines the urgency of the tasks of implementing effective charge air coolers in modern high-pressure transport diesel engines. This technical problem can be solved using air or liquid coolers. The article considers a liquid cooler, because compared to an air cooler, it can be made more compact, allows to achieve a much smaller length and volume of the intake tract, as well as to simplify the layout of the intake tract as part of the power plant as a whole, which is a priority for diesel engines. The article considers the influence of the design parameters of the supercharged air cooler on its overall characteristics and the hydraulic resistance of the supercharged air flowing through the cooler. Thus, the article provides data indicating the possibility of making a compact, highly efficient supercharged air cooler while maintaining its hydraulic resistance at an acceptable level by choosing rational parameters.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91350094","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}
O. Yeryganov, V. Kyrnats, R.O. Brusnik, V.S. Glebov, P.A. Goncharenko, V.I. Holdenko
{"title":"IMPROVMENT OF ENVIRONMENTAL PERFORMANCE TWO-STROKE DIESEL DURING OPERATION","authors":"O. Yeryganov, V. Kyrnats, R.O. Brusnik, V.S. Glebov, P.A. Goncharenko, V.I. Holdenko","doi":"10.20998/0419-8719.2022.2.09","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.09","url":null,"abstract":"The development of world shipping is taking place in the context of ever-increasing requirements to reduce the concentrations of toxic components of gaseous combustion products of hydrocarbon fuels. Concentration limits for these substances are regulated in accordance with Appendix VI of the MARPOL 73/78 Convention. Among the controlled components of diesel exhaust gases, nitrogen oxides are the most dangerous for humans and environment. However, a decrease in the content of nitrogen oxides is inevitably associated with limitations on the maximum cycle temperature, that is, thermal efficiency, and hence with a deterioration in the fuel efficiency of the engine. At the moment, in order to reduce emissions of nitrogen oxides by large transport diesel engines, the most widely used is the recirculation of exhaust gases into the air receiver. A significant disadvantage of using this scheme is the need for cooling the exhaust gases and their additional purification, which leads to an increase in the weight and size characteristics of the system and to its rise in price. Therefore, to reduce its cost, it seems logical to combine exhaust gas recirculation with other ways to reduce nitrogen oxide emissions. For engines in operation, one of these methods is to change the angle of fuel injection. It can be assumed that the later the fuel is injected into the cylinder, the lower the temperature of the air charge will be and, accordingly, the lower the maximum combustion temperature, and hence the amount of nitrogen oxides. The calculation of nitrogen oxide emissions was simulated for the main engine MAN-B&W 7S50MC-C installed on the vessel \"LILA SHANGHAI\". Initially, the model created using the AVL-BOOST package was verified based on the available indexing results. After verification, the calculation of emissions of nitrogen oxides NOx was made with a variation in the angle of the start of fuel combustion at the nominal mode. The composition of the gases in the receiver was taken unchanged. As the fuel combustion start angle shifted further from the TDC, deterioration in fuel efficiency and a drop in cylinder power were observed, while reducing the mass of emitted nitrogen oxides NOx. However, it can be said that the environmental friendliness of an engine improves much faster than its fuel and power characteristics deteriorate. The above calculations show that for engines already in operation, changing the fuel injection angle makes it possible to reduce nitrogen oxide emissions. Therefore, this approach can be combined without much difficulty with other methods, thus reducing the cost of environmental improvement of the engine.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89869393","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}
{"title":"METHOD OF ORGANIZING TWO-STAGE FUEL INJECTION INTO A DIESEL CYLINDER USING A HYDROMECHANICAL FUEL EQUIPMENT","authors":"A. Prokhorenko, S. Kravchenko, E. Solodky","doi":"10.20998/0419-8719.2022.2.04","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.04","url":null,"abstract":"The use of multiphase injection allows reducing the emission levels with exhaust gases and the noise of diesel engines. This paper proposes to improve the hydromechanical fuel supply system of diesel vehicles by providing the possibility of two-stage fuel supply. This task is solved by high-pressure fuel pump equipment, additionally by high-pressure sections that work to inject fuel for pilot injection. The drive shaft cams of these sections are ahead of the shaft cams of the main sections by 2-10 degrees rotation of the camshaft. In order to check the performance of the proposed two-stage fuel supply system and to confirm the possibility of achieving its stated parameters, calculation studies were performed based on mathematical modeling of hydromechanical processes in this system. \u0000Calculation studies were carried out using a mathematical model of the high-pressure fuel system of the Ch12/14 research single-cylinder diesel engine. The mathematical model is implemented in the MATLAB programming environment. Test results of calculations according to this mathematical model for the operating mode of the system at a camshaft rotation frequency of 650 min-1 and full fuel supply, the high-pressure system provides two-stage injection with the following indicators: total cyclic fuel supply 64 mm3/cycle, pilot dose - 9 mm3/cycle (which is 16% of the total cyclical supply); the maximum injection pressure is 49 MPa with a maximum pressure of 58 MPa in the over-plunger cavity; the maximum injection pressure of the pilot dose is 14.7 MPa, while the pressure reached in the over-plunger cavity is 26.5 MPa; the duration of the injection of the pilot dose is about 2 degrees rotation of the camshaft, the main one - 4.7 degrees rotation of the camshaft. \u0000The system also provides two-stage injection in modes according to the load (and speed) characteristics. When the load is reduced from the maximum by 35-40%, it does not affect the maximum injection pressure of the main part of the fuel at all speed modes of the system, after which there is a sharp drop of this parameter to the value of the maximum injection pressure of the pilot. The maximum injection pressure of the pilot dose practically does not depend on the speed mode and lies within 13.5-15 MPa. Since the amount of the pilot dose is not adjustable, it does not depend on the movement of the high-pressure fuel pump rail and is 2 mm3/cycle at a rotation frequency of 450 min-1, 6 mm3/cycle at a rotation frequency of 550 min-1 and 9 mm3/cycle at a rotation frequency of 650 min-1.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84917254","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}
{"title":"USE OF BIOGAS AS A RAW MATERIAL AND ENGINE FUEL IN ENERGY AND TRANSPORT","authors":"A. A. Lisoval","doi":"10.20998/0419-8719.2022.2.02","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.02","url":null,"abstract":"In the article, based on existing global trends, legislative incentives for climate-friendly development of economic sectors, the place of biogas as a raw material and engine fuel in the decarbonization of energy and transport in Ukraine is substantiated. To reduce greenhouse gas emissions, most countries are making the transition from fossil fuels to renewable energy sources. In EU countries, renewable energy with a Green Deal label was equated with energy obtained from the combustion of natural gas. In Ukraine, biomethane is legislated as an alternative gas fuel similar to natural gas. The raw material for biomethane is biogas. In Ukraine, biomethane is not produced on an industrial scale due to the lack of special purification and enrichment technologies at biogas stations. In Ukraine, it is necessary to start producing biomethane on an industrial scale and use the natural gas infrastructure for transporting biomethane. An existing quantity and quality of treatment technologies of biogas plants allow the use of biogas as an independent fuel in cogeneration plants in the immediate vicinity of biogas plants. Calculation of the heat balance of the drive gas engine (8-cylinder, 100 mm cylinder diameter, 88 mm stroke) showed that in addition to generating 30 kW of electrical energy, it is possible to obtain additionally up to 162 MJ of thermal energy without taking heat from the lubrication system. When generating only electrical energy, the efficiency installation in nominal mode is about 30%, and with cogeneration – it increases to 75%. The next step is – the use of biogas as an additive to natural gas in reciprocating internal combustion engines on cars, buses and special agricultural machinery at the local or regional level. The results of research on the 8Ch10/8.8 gas combustion engine ensured the transition from quantitative to qualitative regulation of the fuel mixture of natural gas with biogas additives. An interdependent regulation algorithm has been developed for mixed fuel. With an increase in load, the share of biogas decreases, the mixture is enriched with natural gas. At a load of 75% or more, the enrichment of the fuel mixture occurs more intensively.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91073569","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}
{"title":"INTERNAL COMBUSTION ENGINES AND ENVIRONMENT","authors":"A. Marchenko, I. Parsadanov, O. Strokov","doi":"10.20998/0419-8719.2022.2.01","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.01","url":null,"abstract":"Solution of energy and environmental problems is one of the main tasks of modern times. This paper points out the role of internal combustion engines, especially diesel engines, in the global energy sector and specifically in road transport, consumption of natural resources, negative impact on the environment and global warming. The directions for further improving the efficiency of diesel engines and power plants in road transport are given. These directions are related to the implementation of existing reserves to improve engine efficiency, design, manufacturability, environmental performance and the use of alternative fuels. The leading role of the internal combustion engine as a power plant for vehicles will be complemented in the future by the increased use of hybrid plants consisting of a diesel engine, electric generator, drive motors, energy storage, microprocessor control and optimum control systems. Hybrid plants will be used in passenger transport for urban and intercity haulage, to be installed on private vehicles. When adapted to hybrid plants transmissions, the concept of diesel engine improvement will change in the direction of providing higher operating efficiencies, economic and environmental performance in high boost modes while simplifying its design.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75958564","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}
{"title":"INTERNAL COMBUSTION GAS ENGINES IN SYSTEMS FOR INCREASING THE EFFICIENCY OF FUEL ELEMENTS OF LARGE ENERGY FACILITIES","authors":"V.M. Bgantsev, A. Levterov","doi":"10.20998/0419-8719.2022.2.03","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.03","url":null,"abstract":"The proposed article analyzes the potential possibility of increasing the efficiency of an energy complex with a gas turbine and solid oxide high-temperature fuel cells, into the structure of which an auxiliary piston gas engine of internal combustion is integrated. Natural gas, methane was used as an energy carrier. The subject of the research is indicators of the working process of the auxiliary engine when it is working on mixed gas fuel (carbon monoxide - methane) of variable composition. The research was carried out by the computational and analytical method using a simplified method of calculating the working cycle of a piston engine. Solutions to several problems are considered: disposal of carbon monoxide emissions at the exit from fuel cells during their heating; provision of an additional source of electrical energy for powering methane conversion devices and an additional source of heat for its steam-plasma conversion; utilization of carbon monoxide and residues of incomplete methane conversion. Calculation studies of indicators of the working process of an auxiliary gas engine with a capacity of 100 kW on mixed fuel of variable composition (carbon monoxide - methane) show its stable operation with appropriate correction of the fuel supply regulation system. The effective efficiency coefficient in the entire range of fuel concentration slightly changed (from 0.369 to 0.380). Its growth is observed with an increase in the proportion of methane in the mixed fuel. The average effective pressure of the cycle practically does not change, and the maximum pressure of the cycle during engine operation in the entire range of changes in the composition of the mixture is at the level of 8.0 MPa. Slight change in the maximum temperature with an increase in the concentration of methane in the fuel mixture (from 2117 K to 2048 K) has been noticed. The research testified to the effectiveness of the proposed method of improving the environmental and economic characteristics of the energy complex with fuel cells, by including in its structure an auxiliary gas engine with minimal cost adaptation for operation on mixed fuel of variable composition.","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73119772","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}
G. Frolov, M. Iefimov, V. Kisel, Y. Evdokimenko, D. Borovik, S. Buchakov
{"title":"THERMOPHYSICAL CHARACTERISTICS OF THE HVAF COATING FROM QUASICRYSTALLINE ALLOY OF THE Al-Cu-Fe SYSTEM","authors":"G. Frolov, M. Iefimov, V. Kisel, Y. Evdokimenko, D. Borovik, S. Buchakov","doi":"10.20998/0419-8719.2022.2.11","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.11","url":null,"abstract":"The article deals with the results of determining the thermal conductivity coefficient from quasicrystalline coatings of the Al-Cu-Fe system in the temperature range up to 900 °C. The Al-Cu-Fe quasicrystalline alloy acquires a great interest for practical use as a material for protective coatings. The Al-Cu-Fe alloy is used to produce thermal barrier coatings in internal combustion engines, non-stick coatings on chemical synthesis equipment and in the food industry and to prevent the icing in aviation. The Al-Cu-Fe quasicrystals have low density, high hardness, high elasticity modulus, high values of corrosion resistance and wear resistance, low coefficient of friction, lowered adhesion, low thermal conductivity in combination with the coefficient of thermal expansion, which is close by its value to some metals. The water atomized Al63Cu25Fe12 powder with a dispersion of +40/-63 μm that has a content of the quasicrystalline phase of about 60 wt. % was used for spraying. The coating was sprayed to the butt of a cylindrical substrate from steel 45 (diameter – 25 mm, height – 10 mm), which before spraying was subjected to jet-abrasive treatment by corundum powder with a determining particle size of 1 mm at air pressure of spraying of 0.5 MPa. The Al-Cu-Fe coating with a thickness of more than 0.8 mm was made by high-speed air-fuel (HVAF) spraying using a burner GVO-RV12 with the following spraying mode: the pressure in the combustion chamber of the burner is 1.0 MPa; the oxidant excess coefficient a ≈ 1.2, the spraying distance is 270 mm. The samples were installed on the side surface of the drum (diameter 120 mm), which rotates at a speed of 2.0 rev/s (the speed of movement of the sputtering spot is 0.8 m/s). Spraying was done in three steps of 10 seconds each with a 30 second cooling time between them. Determination of the temperature dependence of the thermal conductivity of the coating was carried out by solving the inverse problem of thermal conductivity by one-dimensional temperature fields in samples obtained by single-sided jet heating with an industrial hot air torch (at surface temperatures up to 450 °C) and an oxygen-propane welding torch (at temperatures above 450 °C). It is shown that the values of the thermal conductivity coefficient of Al-Cu-Fe quasicrystalline coatings in the range of 20 °С…900 °С vary within λ = 1.9 – 2.31 W/(m×K).","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76442366","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}
{"title":"THERMOPHYSICAL CHARACTERISTICS OF THE HVAF COATING FROM QUASICRYSTALLINE ALLOY OF THE Al-Cu-Fe SYSTEM","authors":"O. Linkov, V. Pylyov, S. Lykov, V. Pylyov","doi":"10.20998/0419-8719.2022.2.10","DOIUrl":"https://doi.org/10.20998/0419-8719.2022.2.10","url":null,"abstract":"The article deals with the results of determining the thermal conductivity coefficient from quasicrystalline coatings of the Al-Cu-Fe system in the temperature range up to 900 °C. The Al-Cu-Fe quasicrystalline alloy acquires a great interest for practical use as a material for protective coatings. The Al-Cu-Fe alloy is used to produce thermal barrier coatings in internal combustion engines, non-stick coatings on chemical synthesis equipment and in the food industry and to prevent the icing in aviation. The Al-Cu-Fe quasicrystals have low density, high hardness, high elasticity modulus, high values of corrosion resistance and wear resistance, low coefficient of friction, lowered adhesion, low thermal conductivity in combination with the coefficient of thermal expansion, which is close by its value to some metals. The water atomized Al63Cu25Fe12 powder with a dispersion of +40/-63 μm that has a content of the quasicrystalline phase of about 60 wt. % was used for spraying. The coating was sprayed to the butt of a cylindrical substrate from steel 45 (diameter – 25 mm, height – 10 mm), which before spraying was subjected to jet-abrasive treatment by corundum powder with a determining particle size of 1 mm at air pressure of spraying of 0.5 MPa. The Al-Cu-Fe coating with a thickness of more than 0.8 mm was made by high-speed air-fuel (HVAF) spraying using a burner GVO-RV12 with the following spraying mode: the pressure in the combustion chamber of the burner is 1.0 MPa; the oxidant excess coefficient a ≈ 1.2, the spraying distance is 270 mm. The samples were installed on the side surface of the drum (diameter 120 mm), which rotates at a speed of 2.0 rev/s (the speed of movement of the sputtering spot is 0.8 m/s). Spraying was done in three steps of 10 seconds each with a 30 second cooling time between them. Determination of the temperature dependence of the thermal conductivity of the coating was carried out by solving the inverse problem of thermal conductivity by one-dimensional temperature fields in samples obtained by single-sided jet heating with an industrial hot air torch (at surface temperatures up to 450 °C) and an oxygen-propane welding torch (at temperatures above 450 °C). It is shown that the values of the thermal conductivity coefficient of Al-Cu-Fe quasicrystalline coatings in the range of 20 °С…900 °С vary within λ = 1.9 – 2.31 W/(m×K).","PeriodicalId":35991,"journal":{"name":"Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81585757","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}