COMBUSTION OF GASOLINE AND ETANOL MIXTURE

Thanks to the pressure of the Environmental Society, the priority of engine manufacturers is to reduce emissions of harmful substances into the atmosphere and reduce fuel consumption while constantly increasing engine performance. One way to overcome the aforementioned technical and social problems is to use alcohols, natural or synthetic, such as ethanol to power engines. The objectives of manufacturers of alternative fuels is to provide consumers with the opportunity to use their product without changing the parameters of the main units in their vehicles, therefore the stoichiometry of the combustion of fuel mixtures is important, since this parameter can affect the amount of fuel burned, the quality of exhaust gases and the power of the internal combustion engine. Combustion in a car engine is exothermic, which means that a side effect of this chemical reaction is heat released into the environment. The condition for starting the combustion process is the thermal coefficient – for spark ignition engines – a spark, and for diesel engines – heat during compression of the fuel-air mixture. From the above it follows that after the oxidation reaction in the exhaust gases there should be no residual fuel particles, which in turn is an image of stoichiometric combustion. Since the stoichiometric mixture is very difficult to achieve outside laboratory conditions, a distinction is made between a non-greasy mixture (too much oxidizing agent) and a saturated mixture (too little oxidizing agent), but always strive to reach λ = 1, which corresponds to a stoichiometric mixture. The heavy weight when working with ethanol fuel is the one that affects the operation of the engine and its components. Therefore, it is important to compare the physicochemical data of gasoline and ethanol, as well as mixed fuel – E85. The article deals with the stoichiometry of combustion of an alternative fuel - a mixture of gasoline and ethanol. The economic and environmental conditions that initiated the production of this type of fuel were taken into account, the fuel mixtures were divided according to the content of fuel and oxidants in the combustion chamber. Attention is drawn to the determination of the stoichiometric mixture, as well as to the lambda coefficient (λ), which helps to determine the type of mixture. The properties of gasoline (in the form of iso-octane) and ethanol are described in separate sections and each is compared. One chapter is devoted to the description of the E85 mixture used in Flexi Fuel Vehicles engines, the requirements for this fuel are determined by the Minister of Economy on the requirements for the quality of biofuels, and attention is also paid to the effect of the mixture on the operation of the engine and the content of chemical compounds in the exhaust using E85 biofuel. It has been established that ethanol fuel (in particular E100) is undoubtedly a step forward in terms of ecology, transport economics and the development of alternative fuels. However, its physicochemical properties cause many problems in engine operation. Despite the improvement in the net power generated by the engine, it should be remembered that for the current mechanical parts and their materials, this is a “problem” mixture that requires frequent and accurate diagnostics and calibration. KEY WORDS: STOICHIOMETRIC MIXTURE, COMBUSTION, MIXTURE OF GASOLINE AND ETHANOL, ALTERNATIVE FUEL, IMPROVEMENT OF THE PHYSICAL AND CHEMICAL PROCESSES OF THE ENGINE.

EFFECT OF CONTAMINATANTS IN FUEL USED IN DIESEL ENGINES ON FUEL LUBRICITY

During the production, transportation, distribution, use or storage of diesel fuel, liquid and solid substances get into it, negatively affecting their operational properties. These substances are called pollutants. At the same time, impurities are removed from the fuel by filtration, dehydration and settling. The total amount is the result of the cleaning process. The performance of the aforementioned tasks of the fuel system is mainly determined by the corresponding physicochemical properties of the diesel fuel. The properties of the fuel that affect the functioning of the fuel system are as follows: masticity, viscosity, density, rheological indicators at low temperatures. Failure to comply with the requirements for oil and the content of impurities in diesel fuel can quickly damage injection equipment, which is sensitive to changes in fuel quality. By nature, contaminants of diesel fuel include: dust particles, water, corrosion products of pipelines and tanks, microorganisms, resinous substances. The requirements for diesel oils contained in the PN-EN 590 standard determine the permissible contamination level. The maximum content of solid pollutants for diesel engines is 24 mg / kg. This value is the amount of solids released when filtering a given amount of fuel through a nitrocellulose filter, the pore size of which is less than 0.8 microns. The fifth edition of the World Fuel Charter, September 2013, contains an additional criterion for the particle size of particulate pollutants. A section introduced concerns particles larger than 4 µm, 6 µm and 14 µm. According to the assumption of the division of molecules into corresponding groups of sizes, the purity of diesel fuel is determined by three numbers. These, in turn, correspond to the number of molecules contained in the above size ranges. TDue to the possibility of microbial growth, filter blocking or increased galvanic corrosion, it is assumed that the water in diesel fuel should not be in a separate phase. The permitted water content in diesel fuel is 200 mg / kg. The release of sulfur compounds into the atmosphere increases the concentration of other toxic components in the exhaust gases of vehicles with compression inflammation engines. Sulfur improves the masticability of diesel fuel, but due to environmental protection, its content is systematically reduced. Modern standards for these fuels allow sulfur content up to 10 mg / kg. The content of impurities can be defined as the volume (v / v) or mass (w / m) fraction of impurities contained in a unit volume or mass of the test liquid. There are many methods for determining the content of various types of impurities, from the simplest - visual, through quantitative and qualitative tests, to chemical tests. Four samples of diesel fuel were tested. Diesel (ON) was the baseline. The rest of the samples underwent an accelerated contamination procedure. The pollutants used in the study were: water, gasoline, solid powder abrasive substances consisting of silicon carbide grains SiC (95 - 98%) and impurities Fe2O3, Al2O3, CaO, SiO2, MnO2, granulation 4.5 μm ± 1%. In a baseline test of unstained diesel fuel, a capture force Poz of 930 N was obtained. Capture occurred after 2 s of the test. The sample, a mixture of diesel and gasoline, showed a slight decrease in Poz strength compared to baseline breakdown. The difference was 3%. The time over which the entrainment was observed was similar to the time taken for the baseline sample. During the examination of a diesel fuel sample contaminated with solid particles of abrasive powder, there was a sharp decrease in the gripping force by as much as 97% relative to the result obtained for the base sample, and the beginning of gripping was less than 0.5 s. Tests with a mixture of diesel fuel and water showed a 15% decrease in gripping force, and the time was also 2 s. After comparing the results obtained, it can be concluded that all the impurities used influenced the force of the gripping load. Different results indicate different degrees of influence of certain pollutants on the makability of diesel oil. KEY WORDS: DIESEL, POLLUTANTS, LUBRICANT PROPERTIES, GRIP, GRIP STRENGTH.

WAYS TO INCREASE THE PRODUCTIVITY IN CONTINUOUSLY OPERATING TRENCHING EXCAVATORS

The article considers and reasons the ways and possibilities to create the highly efficient constructions of trenching excavators that dig trenches of the defined profile by means of using bucketless rotors as soil excavating implements together with design of the discharge assembly improved construction. Study objective: to create a bucketless highly efficient rotary implement of the trenching excavator with two-stage discharge. Study object: continuously operation earthmoving machines. Research technique – analytical-experimental. One of the most important problems for the machine-building industry of Ukraine is the efficiency improvement of machines created in the country. Solving of this problem is required due to necessity to perform the increasing amount of earthworks in building and construction works. The cheapest way to perform lengthy soil excavations is to excavate them with trenching excavators. Increasing of their productivity is the one of the main directions to improve the efficiency of the earthworks mechanization. Increasing the efficiency of trenching excavators is possible by means bucketless rotary implement usage and by improving of the rotary discharge process. The study justifies and proves the scientific hypothesis about the possibility to use the force of the soil flow header pressure create by the soil that is being transported from the excavation for the bucketless rotary implements discharge. This allows by means of two-stage discharge of the implement to ensure the full clean-up and to improve the productivity of the soil excavation. The study analytically justifies the requirements for the main construction parameters of the bucketless rotor. Based on the obtained results the technical proposal is created for highly efficient construction of the bucketless rotary implement of the trenching excavator with two-stage discharge. KEYWORDS: BUCKETLESS ROTOR, SOIL, TWO-STAGE, DISCHARGE, DISCHARGE ASSEMBLY, TRENCH DIGGER

DETERMINATION OF THE OBJECTIVE FUNCTION OF THE OPTIMIZATION OF LOSSES OF THE SERVICE STATION RELATED TO THE TYPE OF ORGANIZATION OF ACCEPTANCE AND DIAGNOSTICS OF VEHICLES

The article considers the components of the target function of optimization of HUNDRED losses associated with the introduction of the post (posts) of acceptance-diagnosis with the increase of the set of diagnostic equipment. In particular, the target function of optimizing losses at the service station is presented in the form of an economic criterion that takes into account the maximum possible number of components on which depends the technological efficiency of the service station and the level of "satisfaction" of car owners with services. The object of research is a car service station. The purpose of the work is to conduct a study of the target function of optimization of HUNDRED losses associated with the type of organization of acceptance-diagnosis of cars and to find out algorithms for finding the components of the target function based on the representation of HUNDRED as a queuing system. Research method - analysis and formalization: quantitative indicators of the objective function, methods of forming a group of events, alternative solutions and calculation of the main components of optimization of HUNDRED losses as a queuing system. It is established that the target function of optimization of HUNDRED losses has economic essence and can be presented in the form of complex criterion. It is found that based on the theory of queuing for the area of reception-diagnosis it becomes possible to find solutions of the system of equations that describe its current state, namely: 1) the probability that the system has no requirements, ie free all "workers »Posts and no applications in the queue; 2) the probability of finding the system in a certain state; 3) the probability of denial of the received application for maintenance, ie the probability of finding the system in the last valid state; 4) the average number of occupied reception posts. Similar solutions were found for the TO-R zone. The formulas for determining the components of the duration of the application are considered and given. The formulas for determining the average value of the duration of work in the area of maintenance by the flow of faults and their share in the total flow of applications. The necessity of the 5th - 6th step of building the equipment in the reception-diagnostic area for detection of additional malfunctions (hidden defects) is substantiated. It is established that the average processing time of the application at the posts of acceptance-diagnosis includes three components: 1) the average time of acceptance-diagnosis of the declared ambiguous manifestation of the fault; 2) the average time of additional preliminary diagnosis on the application, which contained ambiguous manifestations of malfunctions. Depends on the number of diagnostic operations performed and the available equipment; 3) the average time of additional diagnosis on the application, which either did not contain ambiguous manifestations of malfunctions, or they did not fall within the capabilities of the existing diagnostic complex at the reception. The results of the article can be used to model the operation of the service station as a queuing system in computer software products and will reveal the low efficiency of diagnosing the main systems of cars in a particular service station. KEY WORDS: DIAGNOSTIC PARAMETER, APPLICATION, PROBABILITY, FAULT, EQUIPMENT, POST, PROFIT, ACCEPTANCE-DIAGNOSIS, SYSTEM.

FEATURES OF LUBRICANE LAYER CREATING IN A LOCAL CONTACT

The article presents the results of research of the influence of the rolling speed parameter during pure rolling and 20% rolling with slip on the kinetics of formation of the lubricant layer thickness in the central contact zone. The aim of experimental research is establishing the impact of operational parameters of friction pairs - speed rolling (a pure rolling and 20% rolling with slip) the dynamics of the process of forming the lubricant layer thickness in the central contact zone between contacting surfaces experimental «steel ball - glass disc.» Oils of various operational purpose were used in the research work, namely motor oils for gasoline and diesel engines (М8Г2К, М10Г2К), universal motor oil (SAE15w40LUX) and universal motor­gear oils (ЄМТ-8, ЄМТ ПРОТЕК) (I-40). The increase in rolling speed was shifted from 0 to 1.8 m / s; at a volumetric temperature (об'ємній температурі) of oils 20°С; contact stress of 251.5 MPa. The thickness lubricating layer in contact was determined by optical interferometry. According to the results of experimental researches concerning determination of the lubricating action of oils in different composition and operational purpose, it was found that during the period of friction steam kinetics of the formation of the lubricant layer thickness depends on the rolling speed - with the increase of which there is an increase in the lubricant layer thickness in the central contact zone, leading to the establishment of appropriate lubrication modes (from boundary to hydrodynamic). Decisive role kinematic viscosity of the lubricant, which depends on the base of oils and quantitative content of the additives. Based on the experimental data obtained in conditions of the rolling with slip, favorable conditions for reducing the initial rolling speed by setting the maximum lubrication regime when using lubricant which contained surfactants with polar molecules. KEY WORDS: ELASTOHYDRODYNAMIC CHARACTERISTICS, ROLLING SPEED, CLEAN ROLLING, SUSPENSION ROLLING, THICKNESS OF THE LUBRICATION LAYER

IMPLEMENTATION OF THE COMMUNICATION PROCESS EFFICIENCY MODEL IN THE PROJECT «FOSTERING THE KNOWLEDG

The study, based on existing approaches to assessing the effectiveness of communication in educational projects, used a method to assess the effectiveness of communication of project stakeholders, the effectiveness of communication planning, the effectiveness of information dissemination, the effectiveness of managing project stakeholders' expectations and the effectiveness of implementation reports. The purpose of the work is to apply the method of evaluating the effectiveness of communication processes in educational and innovative research projects and to analyze the effectiveness of communication in the FKTBUM project. Research methods - project and program management methodologies; mechanisms of set theory, system and process analysis. The developed method of evaluating the effectiveness of communication processes in educational innovative research projects allows to evaluate the effectiveness of communication of project stakeholders, the effectiveness of communication planning, the effectiveness of information dissemination, the effectiveness of managing project stakeholders' expectations and the effectiveness of implementation reports. Thus, the results of the study were used to manage communications in the implementation of educational research innovative projects at the National Transport University in the implementation of the international project TEMPUS - "Fostering the Knowledge Triangle in Belarus, Ukraine and Moldova (FKTBUM) - Supporting the knowledge triangle in Belarus, Ukraine and Moldova" . The results of the project show that the efficiency of communication between NTU and international partners is 0.5 - 1.0, which characterizes the good result of the educational project after the communication process, between NTU and DerzhavtotransNDIproekt - 0.75, which corresponds to the level "given response / reaction to information received", Between NTU and the Ministry of Education and Science of Ukraine - 0.50, which corresponds to the level of " read the information". The results of the article can be implemented in the procedure of evaluating the effectiveness of communications in the formation of the required level of information exchange between stakeholders in the process of implementing innovative technologies in educational activities based on a value-oriented approach. Predictive assumptions about the development of the object of study - the development of a method of effective communication model in educational innovative research projects. KEY WORDS: PROJECT, PROJECT MANAGEMENT, STAKEHOLDERS, EDUCATIONAL INNOVATIVE SCIENTIFIC PROJECTS, COMMUNICATIONS.

INNOVATIVE APPROACH TO INCREASE OF OPERATIONAL SPEED AND PRODUCTIVITY

The article proposes an approach to improving the structure and parameters of complexes for the organization of cargo exchange of piggyback trains using the approach of complex system optimization. The object of study - the process of piggyback transport, methods and approaches to increase its efficiency and speed. The purpose of the work is to determine the methods of improving the efficiency of piggyback transportation and their flexibility in order to adapt its parameters to the needs of customers. Synthesis of methods to increase the flexibility of the piggyback transport system while maintaining consistently high rates of carrying capacity and speed of goods delivery. Research method - system analysis and complex structural-parametric optimization. The organization of piggyback transportation is one of the elements of improving the efficiency and balance of the country's transport system. From the point of view of customer needs, the piggyback system should be flexible, while providing conditions for high transport capacity and speed. To do this, it is necessary to solve a number of problems that would allow the exchange of piggyback trains on the way, without allowing the deterioration of other parameters of the system - mainly performance and speed. The most effective approach to solving these problems is to use the methodology of directed synthesis of complex systems. The peculiarity of this methodology is that it allows you to reach the predefined parameters of a complex system. The synthesized structure of the terminal to ensure highly efficient high-speed freight exchange in the organization of piggyback transport allows piggyback freight exchange at intermediate stations of their route in a minimum time without significantly reducing the route speed and carrying capacity of the system. KEYWORDS: PIGGYBACK TRANSPORTATION, FREIGHT TERMINALS, DIRECTED SYNTHESIS OF SYSTEMS.

DETERMINATION OF THE KINEMATIC VISCOSITY AND DENSITY OF THE MIXTURE OF DIESEL WITH ETHANOL AND DODECANOL

The most popular group of alternative fuels is that derived from renewable sources. This group of fuels includes: vegetable oils and their derivatives (for example, esters of higher carboxylic acids) alcohols (for example, ethanol and methanol) ethers (for example, methyl tert-butyl ether, ethyl tert-butyl ether) liquid biomass processing products ( synthetic fuel). Among this group, the most interesting are alcohols, especially ethanol. This is due to the fact that ethanol has better physicochemical properties than methanol. It can be produced from renewable sources and the manufacturing process is not complicated. Drinking alcohol also reduces emissions of carbon dioxide (CO2) and toxic compounds such as particulate matter and nitrogen oxides (NOx) from diesel engines. By using alternative fuels, costly engine design changes can be avoided and only regulatory changes can be made. The miscibility of ethanol with diesel is influenced by water content and temperature. At a temperature of about 10 ° C, the mixture stratifies. One additive that can be used as a stabilizer for an ethanol-diesel mixture is dodecanol (C12H26). It is obtained by reduction of methyl esters. Dodecanol is solid at a temperature of 24 ° C, insoluble in water and mixes well with diesel fuel and ethyl alcohol. In order for this type of fuel to be used to power diesel engines, it is necessary to know their physicochemical properties, since they have a significant impact on the correct operation of the internal combustion engine, operational parameters and the purity of exhaust gases into the environment. The addition of ethanol to diesel fuel affects key properties such as kinematic viscosity and density. Viscosity affects the atomization and atomization characteristics of the combustion chamber. According to Soter, a lower viscosity value leads to smaller droplet diameters, thus increasing the surface area of the droplets significantly affects the evaporation time of the droplets. Taking into account the processes occurring in the injection systems, the choice of fuel with the optimal viscosity should be a compromise option. On the one hand, the increase in viscosity is favorable due to the efficiency and pressure in the high-pressure pumps and the lubrication conditions of the moving interacting elements of the injection system, but on the other hand, it leads to an increase in energy for pumping fuel into the supply system. On the other hand, an increase in density leads to an increase in particulate emissions. Low density is associated with lower heating value. This will affect the degradation of power and torque. In such a case, in order to reduce the difference, the fuel dose should be increased, the fuel consumption will be increased and the beneficial effect of low fuel density on the reduction of particulate matter emissions will be eliminated. The article presents the results of the study of the issue substantiated the need to measure the kinematic viscosity and density of mixtures of diesel fuel with ethanol and dodecanol. The results of the viscosity measurements can be used to determine the injection parameters and the macrostructure of the atomized fuel flow. KEY WORDS: DIESEL FUEL, ALTERNATIVE FUEL, ETHYL ALCOHOL, DODECANOL, KINETIC VISCOSITY

FEATURES OF THE STUDY OF THE ENVIRONMENTAL SITUATION AROUND THE OBJECTS OF ROAD TRANSPORT INFRASTRUCTURE

In recent years, the state of the road transport infrastructure in Ukraine has deteriorated significantly. With the process of urbanization and the expansion of the transport infrastructure, the ecological danger of the functioning of these strategically important objects increases, which requires effective methods of detailed study of the state of environmental components in areas of urban pollution in order to prevent negative consequences. Working with the problematic, using robots, we analyzed the methods to monitor the environmental situation around the road transport infrastructure for the development of recommendations for advancing efficiency. An algorithm for assessing the environmental situation around the objects of motor transport infrastructure is considered, based on monitoring the impact of these objects on the components of the environment and determining the main factors of this influence. The regularities and dependences of the influence of the motor transport infrastructure from the standpoint of environmental safety have been established. The indicators of pollution of the components of the environment in the study areas and methods of their production are analyzed. It has been concluded that a complex combination of chemical research methods with biodication is observable, makes it possible to analyze the effect of vehicles on various components of the environment (atmospheric air, soil and soil solutions, plants, animals, surface waters, etc.) and to establish the level of anthropogenic load. KEY WORDS: MOTOR VEHICLE INFRASTRUCTURE, ENVIRONMENTAL SAFETY, HARMFUL SUBSTANCES, POLLUTION

MODEL OF SOUND LEVELS CALCULATION FOR NOISE FROM COMPRESSOR STATIONS FOR JUSTIFICATION OF SANITARY PROTECTION ZONE BOUNDARIES

This article is devoted to the study of sound levels for noise from a gas turbine plant and technological equipment of a compressor station in everyday operation, in order to assess the sustainability of the conditions of sanitary protection zones around the compressor station and in order to protect the population living near the compressor station. The main purpose of the study is to assess the compliance of the sizes of sanitary protection zones in terms of noise load on environment. The main source of noise at compressor gas-pumping stations is determined by the noise regime at the industrial site, in addition to auxiliary equipment; include gas-pumping devices, systems of technological gas discharge from the blower circuits, fuel and starting gas of gas-pumping devices. The dependence of the noise conditions at the production site and in the environment on the sound power level of gas-pumping apparatuses, the installed power of gas-turbine plants, the sound power of the turbocompressor, service life of gas-pumping apparatuses, the number of simultaneously operating gas-pumping apparatuses, the characteristics of production premises, the design of the gas-pumping apparatuses, the state of means of noise absorption of gas-pumping apparatuses. In gas turbine installations of compressor stations, intense noise occurs in the air intake and exhaust systems, in the cooling system fan, in the turbomachine housing and in the generator. To calculate the sound levels at a separate point, depending on the distance to the noise source, a model was used taking into account the effects of sound wave propagation in atmospheric air and the characteristics of the noise source, such as: directivity and spectral characteristics of radiation, the height of the source above the surface; distance from the source to the point of determining the sound level; absorption of sound in atmospheric air, depends on the frequency and parameters of the state of the atmosphere; the effect of the influence of the earth; weather effects and others. The methodology of the standard and the international method CONCAW were used based on the results of calculating sound levels at the border of the sanitary protection zone at the compressor station. The calculation results, for standard atmospheric conditions, according to the international CONCAW method indicate that at a distance of 700 m from the sound source, the sound propagation will be 50.0 dBA, which coincides with the calculation results using the standard method and also exceeds the night noise standard by 5 dBA for conditions in the residential area. Development even when only one gas compressor is in operation, which proves the relevance of studying the environmental risks of compressor stations. KEY WORDS: NOISE, ENVIRONMENTAL RISKS, NOISE SOURCE, COMPRESSOR STATIONS, GAS PUMPING UNIT, GAS PUMPING APPARATUS, SOUND.