BACKGROUND: Studies of alternative fuels for automobiles and tractors are of great importance for the development of the Russian engine industry. This trend finds its place in the Transport Strategy of the Russian Federation until 2030, thus being one of the priority directions. Many Russian scientists have been dealing with the problem of multi-fuel capability of internal combustion engines for a long time. This article discusses the operation of the D-245.5S2 diesel engine with biomineral fuel mixtures (BMFM) for their environmental friendliness according to the methodology of UN Regulation No. 96 (02). AIM: Justification of the relevance of the use of biomineral fuel mixtures (BMFMs) for diesel engine operation in various load modes based on a comparison of their final specific emission value with the specific emission of toxic components of pure diesel fuel according to the UNECE Methodology No. 96 (02). METHODS: The following components were used for the preparation of BMFMs: ethanol (E), rapeseed oil (RO) and diesel fuel (DF). Biological components were mixed in different ratios to DF. Their ratio in the mixture was determined by laboratory studies of the physicochemical properties of the components. Subsequently, the mixtures were subjected to bench tests at the facility equipped with the D-245.5S2 diesel engine and the RAPIDO SAK N670 electric brake rig. Further, the obtained total values of the relative terms of the studied toxic components (soot, carbon monoxide, nitrogen oxides, hydrogen oxides) for all test cycles (percent — % and millionths — ppm) were converted into the actual content of these substances in the total specific emission in exhaust gases (according to UN Regulation No. 96(02) — g/kWh). RESULTS: It was found that the use of these mixtures has a positive effect on the environmental component of the exhaust gases: a decrease in the emission of the studied toxic components was observed when operating with the BMFMs in comparison with traditional diesel fuel. CONCLUSION: Although BMFMs show reduced emission values of harmful substances in exhaust gases compared to pure diesel fuel, they cannot make a diesel engine to satisfy the environmental indicators of the Stage II of the UNECE Regulation No. 96 (02); optimization of the fuel supply system and installation of additional exhaust gas filtration systems are necessary.

The composition of a tool material based on WC–Co is investigated. The TiAlN surface coating is studied. The physicomechanical properties of hard-alloy end mills produced by Guhring and LEPSE Electrical Machine Plant are analyzed.

The paper presents theoretical and experimental studies of the working process of the 4ChN 11.0/12.5 (D-245.5S2) diesel engine operating on diesel fuel with addition of the liquefied hydrocarbon gas by a separate system into the intake manifold. Regression dependences were obtained of the relative specific effective fuel consumption and the main ecological indicators of the diesel exhaust gases on the fuel injection advance angle. Dependences are provided of torque, specific effective fuel consumption, maximum cylinder pressure, working process rigidity, content of solid particles and nitrogen oxides, as well as of total emission, on the amount of the supplied liquefied hydrocarbon gas into the diesel engine. The indicator diagram and the diesel engine heat release characteristic were analyzed with operation on the diesel fuel and with addition of the liquefied hydrocarbon gas. The experimental setup is described. Theoretical and experimental results were compared. The amount of liquefied hydrocarbon gas supplied to the diesel engine not exceeding 30% of the diesel fuel consumption was substantiated. Convergence of experimental and theoretical data at the level of 6.3% was confirmed. It was established that the diesel engine operation with addition of up to 30% of the liquefied hydrocarbon gas made it possible to reduce total emission of the particulate matter and of the nitrogen oxides in the exhaust gases by 20.2%.

Introduction. The review of literature sources has shown that at the moment there are no reliable methods, which theoretically determine the main parameters of axial devices for threshing grass seeds and it is necessary to conduct researches to establish a mathematical relationship between these parameters and quality indicators. Aim of the Article. The article aim is theoretical substantiation of the dependence of the main parameters of axial devices for threshing grass seeds on the quality requirements to the technological process of threshing grass seeds. Materials and Methods. A set of priori information about the operation of axial rasp-bar threshers, the analysis of literary sources and own observations of the working process of the clover thresher K-0.3 allowed determining the basic prerequisites to develop an algorithm for solving the task. Results. As a result of theoretical consideration of the process of moving particles of the processed material in the working space of a drum-deck axial-rotor device for threshing grass seeds, a system of mathematical equations is obtained. The solution of the resulting system of equations makes it possible to determine the average axial velocity of the particles and a number of impacts inflicted by the rasps on them during movement. There is obtained an expression for linking the degree of seed threshing and main parameters of the device such as length, a number of rasps and the direction of their cleats, and the frequency of rotation of the drum. Discussion and Сonclusion. It was found that the degree of seed threshing significantly depends on both the length of the threshing device and a number of drum rasps and the direction of their cleats. The theoretical dependencies obtained as a result of the study make it possible to determine the main parameters of axial devices for threshing seeds, depending on the requirements imposed on the device.

The paper studies the combustion process that ensures operation of a tractor diesel engine with external mixture formation to determine type and proportion of the gas fuel added to the tractor diesel engine cylinders with fresh charge providing alteration in the mixture formation from internal to the external. To confirm reliability of the theoretical assumptions, the 4CHN 11.0/12.5 (D-245.5S2) diesel engine was experimentally studied on the RAPIDO SAK N679 load electric brake stand (Germany) with the 250 kW balancing pendulum machine and using specialized equipment for indexing. Alteration from the internal mixture formation in the tractor diesel cylinders to the external occurring at the constant diesel fuel injection rate was theoretically substantiated. For the given load-speed operation mode, the type of gas fuel was determined, i.e. the propane-butane mixture added to the main diesel fuel in an amount of 38% or more by weight. It was experimentally established that addition of up to 40% gas fuel to the diesel fuel completely eliminated the diffusion phase in the combustion process, which indicated transition of the diesel engine operation from the internal mixture formation to the external.

Introduction. Physico-chemical properties of the diesel fuel emulsion with Brassica rapa oil and ethanol have been studied. The use of blended fuel does not make structural changes in the engine, but only the improvement of the attachments: the power supply system of the internal combustion engine. Aim of the Article. The article aims at determining the effect of additives of Brassica rapa oil and ethanol in commercial diesel fuel in different quantities on such indicators as density, kinematic viscosity, and the lowest specific heat of combustion of mixtures and determining the optimal mixture of fuels for bench tests on the diesel. Materials and Methods. There were used the following equipment: laboratory scales VIBRAAJH-620CE, pycnometer PZh2-10-KSh 7/16, viscosimeter VPZh-2, and electronic stopwatch. Results. The dependence between the density, kinematic viscosity and concentration of additives in blended fuels has been determined. The relationship between the kinematic viscosity of oils and the lower specific heat of combustion has been noted. The dynamics of a decrease in the average lower specific heat of combustion of blends relative to an increase in the concentration of blended fuels is presented. Discussion and Conclusion. For bench tests on the engine, there were selected two blends 10% Brasssica rapa +10% Ethanol+80% Diesel and 25% Brasssica rapa +25% Ethanol +50% Diesel. When selecting the mixtures, the focus was on 4 parameters: kinematic viscosity, density, stability time, and lower specific heat of combustion.

BACKGROUND: Intensive development of the transport sphere and the extension of the fleet of tractors and cars, as well as the tightening of standards and requirements in the field of exhaust gas emissions have resulted in increased requirements for the combustion process. This problem can be solved by improving the working process in the engine by preheating the fuel to 300 C in the high pressure fuel supply system. Under external thermal influence, the conditions of mixture formation are improved, an increase in the rate of preflame reactions and a positive change in the dynamics of the combustion process are observed. When potential energy of hydrocarbon molecules increases in the activated complex system, energy is redistributed among active molecules. Along with this, the rate coefficient of a chemical reaction increases due to the concentration of foci of hydrocarbon molecules that have reached the energy barrier. The object of research is the process of diesel fuel combustion at preliminary external influence on it. AIMS: The aim is to study the combustion process of a motor-tractor diesel engine upon fuel activation. Development of a scheme of individual phases of the activated diesel fuel combustion of depending on the temperature at heating. METHODS: Theoretical study and analysis of the combustion process of thermally preprepared fuel for an automotive diesel engine. Theoretical determination of the dependence of the rate of formation and concentration of toxic components and dispersed particles on the rate constant of direct and reverse chemical reactions, as well as on the activation temperature of fuel at emission in exhaust gases. RESULTS: The actual coefficient of molecular change of the working mixture increases when diesel fuel is activated. The rate of formation of total nitrogen oxides and hydrocarbons increases by 1.79% and 3.66%. The proportion of unburned carbon in the combustion process on activated fuel varies within (24) %. CONCLUSIONS: Theoretically, a scheme for changing individual phases of the activated fuel combustion process by time and temperature has been developed. Fuel heating accelerates the pre-flame preparation in the liquid phase, shortens the duration of the rapid gorenje phase. The concentration of toxic indicators depends on the constant of the chemical reaction rate and the activation temperature of the fuel.

The aim of the study is dependences of the indicators of the combustion process of a diesel engine when it is operating on various mixed fuel (MF). For this, an experimental setup was developed. As a result of the studies carried out, for the first time, combined indicator diagrams and the dependences of the averaged cycle temperature on the crankshaft angle were obtained when the diesel engine is operating on various MF. Data analysis showed a decrease in the maximum pressure in the cylinder from 11.5 to 11 MPa, the maximum and average rate of pressure rise from 0.65 to 0.5 and 0.24 to 0,2 MPa/degree, respectively, shortening the fast combustion phase from 6.5 to 4.2 degrees and the period of slowed-down combustion from 40 to 34 degrees, a decrease in the average temperature of the cycle from 2920 to 2810 K, an increase in the apparent combustion pressure from 7.4 to 7.6 MPa, the ignition delay period from 20.4 up to 22.5 degrees, increasing the period of controlled combustion from 10 to 14 degrees, the period of the main combustion by 4 degrees when the share of rapeseed oil in MF changes from 0 to 80%.

BACKGROUND: When conducting experimental studies aimed at finding optimal parameters of the diesel engine operating mode, as well as other objects, the issue of reducing the volume of the experiment becomes acute. The use of modern methods of planning, obtaining, processing and analyzing experimental data allows to reduce significantly the number of experiments conducted without notable loss of the reliability of the data obtained. AIMS: The aim of this study is to determine the optimal operating characteristics of the diesel engine, which uses the multi-component bio-fuel composition. METHODS: In order to determine the optimal values of the main parameters, affecting the effective indicators of the 4ChN 11.0/12.5 diesel engine when operating on the multicomponent biofuel composition and a mathematical description of their relationship, a second-order three-factor Box Benken plan was implemented. These factors are effective load, crankshaft rotational speed, and fuel injection advance angle. The diesel engine operation studies were performed on the most stable mixture of the multicomponent biofuel composition, including the following ingredients, wt %: rapeseed oil 34.5; ethanol 31.0; diesel fuel 34.5. The search of a compromise solution for the optimal combination of the levels of studied factors was performed with the method of superimposing of bidimensional sections of the response surfaces of the effective efficiency factor and the specific effective fuel consumption. RESULTS: Adequate models of second-order regression analysis of changes in effective efficiency factor and specific effective fuel consumption have been obtained. The factor space is described and grapho-analytical studies are carried out. The analysis of regression models and bidimensional sections of response surfaces allowed to determine the optimal values of the studied factors. The method for determining the optimal load and speed ranges of the diesel engine operation, using the multicomponent biofuel composition, has been optimized due to the application of the experimental plan and the description of the factor space by mathematical models, while number of experiments was reduced. CONCLUSIONS: The optimal area of the combination of the factors is in the range of varying the rotational speed of the diesel engine crankshaft n=1400...1550 rpm and the effective load Pe=0.68...0.85 MPa at the fuel injection advance angle Ѳinj=23.5 degrees to TDC. Considering the variable nature of the load and speed modes of a diesel engine in a real operation environment, the obtained data are of practical interest.

The urgency of mathematical simulation and electronic processing of obtained experimental data for estimating the working process increases by the day. The solution of real-world problems requires high-speed computer programs that enable us to reliably simulate complex processes occurring in engines and to simplify a considerable part of research effort. In connection with these considerations, the aim of our investigation is the improvement in the methods for estimating the nature of the working process of an internal combustion engine by applying CNIDI techniques for processing indicator diagrams by designing a hardware and software package. The package is able to present the obtained design data of heat-generation law values in a readable form of a digital model that enables us to produce their subsequent export into other software products for further research. The novelty of our work lies in developing a program for personal computers which is able to process experimental indicator diagram obtained in any form and by any technique for acquisition of heat-generation values. The main purposes of our investigation are the analysis of existing CNIDI techniques of processing indicator diagrams, the algorithm design of computer software operation and the verification of data obtained by programmed methods with design data. We found that applying the technique of processing experimental indicator diagrams is one of the methods most reliably describing the processes occurring in diesel cylinders. We analyzed the theoretical basics of a fuel combustion process by using experimental indicator diagrams, examined taking into account imprecision of source data, and validated ways of updating the data. We upgraded the computer program aimed at the methods of heat-generation data calculation under combustion according to specified diagrams. The use of introduced CNIDI techniques and the appropriate program of indicator diagram analysis provide the required quality of results in investigating the influence of various factors on fuel combustion process in an engine.

The relevance of the study is stipulated by the necessity for determining of optimum composition of water-fuel mixture (WFM) for a spark-ignition internal combustion engine with electronic control. The objective of the study is the determining of the optimum composition of water-fuel mixture (WFM) during the operation of a VAZ-21114 engine which allows for the best quantitative performance specifications. For this purpose, an experimental test fixture was developed, consisting of a KI-2139 electrical brake bench with a pendulum arm machine and an “AVTOTEST-02.03” 5-component gas analyzer, with equipment for bench testing in accordance with the requirements of GOST 14846-81 “Automotive engines. Bench test methods”. As a result, for the first time, optimum quantitative WFM composition was obtained for operation of VAZ-21114 spark-ignition engine with electronic control providing for the best quantitative performance specifications. The analysis of the obtained data demonstrates lowering of the concentration of toxic exhaust gas (EG) components of the engine, specific effective (ge ) and hourly (Gm ) fuel consumption rate, as well as the EG temperature (Toe ) during its operation by the external rpm vs. load curve within the utilization range of WFM with 0 to 12% water content. At water content growth in the WFM from 12 to 20%, a growth of carbon monoxide (CO) and unburnt hydrocarbons (CH) in the EG is observed, as well as a growth of ge and Gm . The minimum quantitative values of the parameters CO, CH, NOx, Toe, ge and Gm were: 6.0 and 1.65% of CO at water content in WFM of 10 and 13%, respectively; 173 and 142.5 ppm of CH at 10% water content in WFM; 113 and 215 ppm of NOx and Toe 650 and 730 К at up to 20% water content in WFM; ge 330 and 303 g/kWh at 12.5 and 11.5% water content in WFM, respectively, Gm 6.5 kg/h at 11.5% water content in WFM. The maximum quantitative value of the effective engine power Ne of 44.2 kW was obtained with WTM with 20% water content. The obtained results demonstrate that, for the operation of a spark-ignition type VAZ-21114 engine with electronic control, the WTM should contain 9…12% water as an optimum providing for achievement of the best quantitative performance values.

A problem of reduced number of tests was identified during the determining of optimal load and speed performance of a diesel engine with a multi-component bio-fuel composition. The planning method of the experiment for determining of effective ICE performance was improved. For factor space description, graph analyses were carried out using a semi-rotatable 2nd order Box-Behnken statistical design for three factors. The operation studies of a 4ChN 11,0/12,5 diesel engine were performed with the most stable multi-component bio-fuel composition, including the following ingredients, % wt.: RSO – 34.5; ethanol – 31.0; DF – 34.5. The analysis of regression models and 2D sections of response surfaces provided for determining of the optimum advance angle of fuel injection Θɞnp . = 23.5 deg. to TDC. By method of superposition of the 2D sections of the response surfaces of the effective efficiency η e and the specific effective fuel consumption g e a search for a compromise solution on optimum combination of the levels of the factors to be studied. It was found out that the optimum area of the combination of factors is located in the range of the crankshaft rpm n = 1400…1550 min −1 of the diesel engine and in the effective load range P e = 0.68…0.85 MPa. Under recognition of the variable nature of the load and speed modes of a diesel engine in a real operation environment, the obtained data are of practical interest.

Local types of fuels occupy 33.6% in the fuel balance of the Kirov region. The share of consumption of local fuels in the region is one of the highest in Russia. The Vyatka State University (VyatSU) in cooperation with the Belarusian State Agricultural Academy (BSAA) carry out the tests of the operation of automotive diesel engines on fuels with rapeseed oil (RO) and ethanol (E) additives, and spark internal combustion engines with generator gas (GG) additives. A new area of work of the scientific school is the study of the use of multicomponent compositions of biofuel compositions (MKBTK-15 and MKBTK-25). The use of such compositions as a fuel compensates some of their distinctive properties for further use in internal combustion engines without changing the design and adjustments. The use of alternative fuels (AF) in internal combustion engines is a main topic for research. However, the use of any AF requires that the environmental indicators of the engine remain within acceptable limits. An important task is to determine the dependences of the emissions of toxic components on the load. The use of MKBTK-15 and MKBTK-25 as AF for engines will improve the environmental situation in the region and reduce the need for commercial fuel. The operation of a diesel engine on multicomponent biofuel compositions makes it possible to reduce the smoke content of exhaust gases by 65% and 85%, the content of total nitrogen oxides remains at the same level or slightly decreases. There is a slight increase in the content of carbon dioxide СО2 up to 22.3%, but the solutions to this problem are already known. One of the ways is to preserve and increase boreal forests, which have great potential for absorbing greenhouse gases.

In the recent years, no considerable growth of use of alternative fuels by vehicle fleets has been observed, in spite of the availability of a vast volume of research data and recommendations. The identified reason is the reluctance of manufacturers to produce ICE modifications for operation with fuels different from DF. The problem could be solved by development and study of ways to extend the multifuel capability of ICE. Basic ways were identified to extend the limits of the usability of alternative fuels with different physical and chemical properties. Regressions were suggested allowing for determining the chemical nature of additives and their degree of influence on the decreasing of the kinematic viscosity of the fuel. A mathematical solution was obtained describing conditions of physical existence of a fuel emulsion. An analysis of a number of combustion inhibitors was carried out. A mechanism of inhibition of additives of new generation was analyzed. Subcaloric fuel combustion process (generator gas) was studied, ways to improve its efficiency were suggested. Based on the theoretical analysis and experimental data, generalized assessment criteria were formulated for the usability limits of non-conventional energy materials. The obtained results could help to essentially extend the fuel base of engines in real operation environments.

Introduction. The expansion of the fleet of tractors and vehicles causes increased requirements for internal combustion engines. This problem can be solved by improving the work process in a diesel engine that can be achieved by heating the diesel fuel in the fuel supply system. External thermal action is carried out on the high pressure line directly in front of the injectors. Materials and Methods. To analyze and calculate the process of combustion and heat release in a diesel engine with preliminary thermal fuel preparation, bench tests were carried out using the National Instruments software and the necessary equipment. Results. Experimental data of the diesel fuel combustion process in the cylinder of the 4CHN 11.0/12.5 engine are obtained. The analysis of the combustion performance and heat release of diesel with a preliminary high-temperature effect on the fuel was carried out. Indicator diagrams, graphs of heat release, the maximum average temperature of gases in the engine cylinder, and graphs of active and total heat release were constructed. The experimental data showed a decrease in the ignition delay period, the maximum cycle temperature in the engine cylinders, and an acceleration of the start of heat release and combustion process. The values of the parameters of the diesel fuel combustion process are obtained. Discussion and Conclusion. On the basis of the conducted studies, the dependences of the parameters of the combustion process of a diesel engine with fuel heating to high temperatures are revealed. Indicator diagrams allow drawing a conclusion about the influence of the fuel heating temperature on the intensification of the combustion process. There is an acceleration of the beginning of heat release, a decrease in the rate of pressure build-up and in the rigidity of the engine.

Проблема и цель. Цель исследований – определение оптимальных регулировочных значений топливоподающей аппаратуры (ТПА) дизельного двигателя Д-245.5S2, широко применяемого в народном хозяйстве, при использовании многокомпонентного биотоплива. Объекты и методы. Объект исследований – экспериментальная установка, включающая дизель Д-245.5S2, моторный стенд RAPIDO SAK N670, разработанные составы многокомпонентных биотоплив. Содержание стендовых испытаний определялось ГОСТ 18509-88. Исследовалась работа двигателя на чистом дизельном топливе (ДТ) и многокомпонентных биотопливных композициях (МКБТ) с присутствием 15 % и 25 % этанола и рапсового масла, каждого. Методика испытаний включала снятие регулировочной характеристики. Меняли установочный угол подачи топлива в номинальном режиме работы объекта исследований. Не менее, чем при семи значениях угла фиксировались выходные показатели. Ход экспериментов. Значения дымности и токсичности, мощности и экономичности фиксировались, данные эксперимента и последующих расчетов наносились на график. Результаты и выводы. В результате анализа данных были выявлены наиболее приемлемые, с экономической точки зрения, интервалы изменения регулировок системы впрыскивания топлива. изменения токсичности и дымности отработавших газов при разных составах топлива. Problem and the purpose. The purpose of researches - defnition of optimum adjusting values submitting fuel equipments (SFE) the diesel engine D-245.5S2 widely applied in a national economy, at application of multicomponent biofuels. Objects and methods. Object of researches - the experimental installation including diesel engine D-245.5S2, electrobrake stand RAPIDO SAK N670 with балансирной by the balance pendular machine, new structures fuels. The contents of bench tests was determined GOST 18509-88. Job of the engine on pure diesel fuel(DF) and multicomponent biofuel compositions (MCBT) with presence of 15% and 25% of ethanol and rape seed oils, everyone was investigated. The technique of tests included removal of the adjusting characteristic. Changed an adjusting corner of submission of fuel in a nominal operating mode of object of researches. Not less, than at seven values of a corner target parameters were fxed. Course of experiments. Values smokiness and toxicity, power and proftability were fxed, data of experiment and the subsequent calculations were rendered on the schedule. Results and conclusions. As a result of the analysis of data the most comprehensible have been revealed, from the economic point of view, intervals of change of adjustments of system of injection of fuel. Changes of toxicity and smokiness the fulflled gases at diferent structures of fuel.

Introduction (problem statement and relevance). Today, vegetable oils, in particular, rapeseed oil (RO) are widely used types of fuels for diesel engines. The main physicochemical properties of RO are somewhat similar to diesel fuel (DF). However, one can highlight a large fraction of the oxygen content in it, which affects the fuel combustion intensity in diesel cylinders. In this regard, the addition of rapeseed oil is very important to optimize the composition of mixed fuel (MF) for its use in diesel engines. The purpose of the study was optimizing the MF composition and obtaining experimental data of diesel engine effective performance by means of regression analysis. Methodology and research methods. To optimize the MF composition studies were carried out to determine the relative fractions of carbon, hydrogen, oxygen in RO and MF, as well as bench tests of diesel fuel and MF with various RO additives operation, followed by the regression analysis of effective indicators. Scientifi c novelty and results. The effective performance dependences of the diesel engine on the RO content in the MF have been determined. Basing on the obtained load characteristics of the diesel engine, it was concluded that an increase in the average effective pressure from 0.2 to 1.2 MPa, as well as in the share of RO in MF from 0 to 80%, would lead to an increase in the effective specifi c fuel consumption to 383–506 g/kW·h and the decrease in effective effi ciency by 14–28%. On the basis of the regression analysis the maximum values of the optimality criterion indicators D-optimum = 0.98–1.0 with the addition of RO to MF from 45 to 50% were determined. Practical signifi cance . The value of the maximum permissible composition of MF, consisting of 50–55% of diesel fuel and 45–50% of RO and ensuring maximum compliance with the specifi ed conditions of optimality on the diesel engine under consideration has been obtained.

The internal combustion engine is the most widespread source of energy for vehicles. The main requirements for an internal combustion engine include: the efficiency of functioning as part of a vehicle, high performance indicators, as well as environmental parameters of the emission of exhaust gases into the environment. The fulfillment of these conditions is possible by improving the design of the engine, as well as improving the working process of the diesel engine while increasing the quality of diesel fuel or additional impact directly on the fuel itself. One of the most effective ways to influence diesel fuel is to transfer a certain amount of heat to it in the high-pressure fuel line in front of the injectors. At the same time, the physical and mechanical properties of diesel fuel change, which leads to a change in mixture formation and the combustion process in the engine cylinder. To intensify the combustion process, a method of preliminary high-temperature local heating of diesel fuel in the fuel supply system in front of the injectors was proposed. To achieve this goal, several main directions were identified, including the study of environmental indicators during the intensification of the combustion process. The tests were carried out in stages. At the first stage, the operation of the fuel injector when operating on activated fuel (bench, laboratory tests) was investigated. At the next stage, the indicators of the diesel engine in the main modes of its operation were investigated. Bench (laboratory) tests made it possible to draw a conclusion about the operability and compliance of the aggregate with the technical requirements of the manufacturer and the parameters of GOST. The bench tests proved the possibility of a diesel engine running on activated fuel without deteriorating environmental performance in the exhaust gases; at the same time, changes in the toxicity and smoke of the exhaust gases from different values of the average effective pressure were revealed.

The relevance of this work is due to the need of preliminary engineless assessment of performance factors for diesel engines working on alternative fuels. The aim of the work is a development of programmed techniques for performance characterization of a diesel engine. The work was carried out according to a standard methodology for determining combustion procedure performance factors developed by the Central Research Diesel Institute and Bauman Moscow State Technical University. The authors suggested performance calculation algorithms for preparatory and master phases of the combustion procedure in a diesel engine cylinder working on composite fuel and emulsions doped with aliphatic alcohols and plant oils. A calculation and a comparative assessment of precision of measurements in design and experimental data of an ignition delay period, cycle peak pressure and combustion procedure inflexibility were performed. Based on the results of the research, conclusions were drawn on the possibility of a preliminary performance assessment of diesel engines working on alternative fuels and potential effect of suggested research methods. Using the suggested makes it possible to forecast the performance of a diesel engine working on liquid alternative fuels. The results of the research can be applied to developing new kinds and compositions of alternative fuels as well as to assessing necessary remodeling of diesel engines in their practical application.

Introduction. The relevance of the study is determined by the need to estimate the influence of mixed fuel, including diesel and biofuel (rapeseed oil), on ecological parameters of an agricultural tractor diesel in working in agricultural fields and transporting. The objective of the study is forecasting, obtaining and comparing the calculated and experimental environmental performance indicators of the Belarus-922 tractor diesel engine using mixed fuel for farming operations. Materials and Methods. To achieve the objective of the study, the quantitative indicators of component structure of rapeseed oil samples of various origins have been defined, a theoretical estimation and the comparison of calculated and experimental environmental performance indicators of tractor diesel engine have been made with the use of the necessary equipment. Results. For the first time, quantitative values of indexes of the component composition of rapeseed oils of various origins have been obtained. The analysis has shown that the most recommended to be used as fuel is the sample with the maximum content of unsaturated acids that will allow providing the maximum speed and combustion efficiency. The calculations show a decrease in working temperature by 200 K as a result of added rapeseed oils that should lead to a reduction of the constant of the reaction speed and concentration of nitrogen oxides approximately by a factor of 2.7. The endogenous origin of nitrogen compounds influences essentially on the concentration of nitrogen oxides in worked-out gases. Discussion and Conclusions. Based on the analysis of nitrogen oxide mechanisms on combustion of rapeseed oils, the calculation of the semi-quantitative reaction rate is theoretically proved and experimentally confirmed.