The application of alternative fuels in diesel engines is relevant because of the exhaustibility of mineral fuel resources, and the necessity to reduce exhaust gases (EG) toxicity. The most acute problem of diesel engines, if the growing requirements for reducing the toxicity of exhaust gases are taken into consideration, is the reduction of NO_x and particulate emissions. The problem can be solved by optimizing the engine working process by means of biodiesel fuel usage. It is well known that the simultaneous reduction of smokeness and NO_x concentration is quite difficult. It is also known that the toxicity reduction can be achieved by crushing the cyclic fuel feed into two or more parts by changing the fuel injection pressure and changing the advance angle of the pilot and main fuel portions, as well as after fuel injection. The adjusting characteristics have been determined by the advance change of injection angle of the pilot and main fuel portions, the pilot portion fuel mass, and by the injection pressure on the biodiesel fuel. As a result of the determining of the regulating characteristics the dependence of the power and environmental indicators on the adjustment parameters was discovered. It was found out that the most significant impact on the biodiesel engine running was made by the fuel injection pressure and the advance injection angle of the main fuel portion. These adjusting parameters influenced both the power change of the diesel engine and the toxicity of the exhaust gases. The pilot portion mass and the advance injection angle of the pilot dose affected, to a greater extent, the toxicity of the exhaust gases. As a result of the tests, optimal variable ranges of the adjustment parameters for each loading mode were revealed and recommendations for the fuel equipment tuning were given.

One of the actual tasks facing the engine building industry is the forcing and upgrading of existing medium-speed diesel engines to meet modern requirements and environmental standards. The required upgrading leads to an increase in the maximum operating temperature, and, as a result, to an increase in the thermal stress of parts contacting with hot gases. The purpose of this paper is the calculation of the boundary conditions necessary for calculating the heat-stressed-deformed state (HSDS) of the cylinder cover. In order to obtain a reliable result, modern software systems are to be used to determine the local loads on the main engine parts. For this, a three-dimensional non-stationary calculation of the diesel working process was carried out in the AVL Fire software package in the Fire Workflow Manager module, possessing physical-chemical models of a deep level of detail. The results of calculation in the zero-dimensional program complex “Dizel’-RK” were used as the initial data for modelling. The calculations were carried out using various combustion modes: Magnussen-Khartager (here the parameter B was varied) and the three-zone extended model of a coherent flame. The verification of the obtained indicator diagram of the diesel CHN21 / 21has been carried out by comparing the calculation results with the experimental data obtained during the testing of the engine at “UDMZ” Ltd. As a result of the three-dimensional non-stationary calculation of ChN21/21 diesel workflow, the values of non-stationary thermal boundary conditions of the second kind on the part of the working piece have been obtained, which will be later used to calculate the HSDS of the main engine parts forming the combustion chamber. The resulting calculation indicator diagram had a high convergence with the experimental diagram.

The article presents the results of experimental studies of the thermal conductivity, heat capacity, viscosity and density of cooling “nanofluids” which represent a two-phase mixture of aqueous solution of ethylene glycol and nanoparticles of graphene oxide. Graphene oxide, which is a multi-graphene laminate compound with covalently bound oxygen with a number of layers from 1 to 10, was obtained by ultrasonic exfoliation of graphite oxide. The known theoretical models for the thermal conductivity and viscosity of two-phase nanofluids may not coincide with the experimental data, which makes it difficult to use these models to predict the properties of the nanofluids being created. The effect of graphene oxide particles concentration and the nanofluids temperature on their thermal conductivity, heat capacity, viscosity and density is shown. When choosing among existing or while creating and investigating new cooling liquids, it is advisable to compare not only their individual physical properties (for example, thermal conductivity or viscosity), but the entire complex of their features (thermal conductivity, viscosity, heat capacity, density) that determines their “cooling” properties, called the cooling complex. A quantitative evaluation of the water and antifreeze cooling complex and the investigated nanofluid has been presented. Differences in nanoparticle obtaining technologies, in their sizes, shapes, concentrations, and physical properties of base liquids affected the thermal conductivity, heat capacity, viscosity and density of cooling nanofluids and, as a consequence, the heat transfer coefficient. The obtained results of the measurement of the thermal conductivity coefficient, viscosity, heat capacity, and density of the cooling nanofluid allowed us to reasonably approach experimental studies of the heat transfer between the heated wall of the part and the cooling fluid at different coolant velocities, pressures, temperatures and concentrations of nanoparticles.

Pilot tests have been carried out to evaluate the effectiveness of side airbags to determine the indications of the driver (passenger) injuries of a M1 category vehicle in side collisions. Seven cars of different manufacturers and in different configurations were taken as objects of research. The tests were carried out in accordance with UN Regulation No. 95 using a special Euro SID-1 dummy and a deformable impactor. Comparing the test results of cars not equipped with protective cushions and inflatable screens, it could be concluded that in the side collision the level of driver and passengers protection was significantly influenced by the design of the power elements placed in the doors of vehicles and which prevent the spread of the deformation zone to the area of the ribs and abdomen of the EuroSID-1 dummy. Compared to cars not equipped with side cushions, the use of side airbags to protect the head of the driver and the passenger could reduce the rate of head injury more than 7 times, on average. The use of side cushions placed in the backs of the seats could reduce the damage of the ribs and pelvic injuries by 4 times, and the rate of injury of the abdominal section was 1.5 times. It should be recommended to include a section defining the regulated requirements for side airbags in the UN Regulation No. 95, including the following paragraph “The time for the full disclosure of inflatable restraints used to protect the driver and passengers in side impacts should be no more than 15-20 ms”.

The object of the study is the undercarriage of wheeled vehicles - frame, housing and body. The subject of the study is the ways of calculating the stress-strain state of the wheeled vehicles undercarriages on the basis of the finite element method. The aim of the work is to reduce the calculation complexity when considering a large number of calculated cases with the help of loading automation and the formation of boundary conditions by the usage of the inertia relief (inertial unloading) method and the solid-state dynamic vehicle. On the example of a complex undercarriage with articulated joint, two types of calculations have been carried out: using the inertia relief method and a solid-state dynamic model; and the use of the “classical” method of specifying loads through simplified beam-rod suspension model, wheels, steering, and anti-roll bar. Calculations of both models were performed for several calculation cases typical of the undercarriage. The results of the calculation proved the adequacy of the obtained stress-strain state determination by the method of calculation of inertia relief in comparison with the “classical” method. At the same time, it was concluded that the load affecting the undercarriage was more accurately determined by the applied inertia relief method compared with the “classical” loading method of the undercarriage since the local changes in the acting forces direction were taken into account at the attachment points of suspension as well as in the other mechanisms for different calculation cases. The comparison of calculations showed that the application of the inertia relief method not only provided greater accuracy in calculating the stress-strain state of the vehicle undercarriage in local areas, but also significantly reduced the complexity of calculations when considering a large number of calculated cases by automating the formulation of boundary conditions and loads when transferred from solid-state dynamic model of the vehicle.

The vehicle moving in space without direct human participation, ceased to seem something supernatural or fantastic. Today, there are cases of fairly successful implementation of a motor vehicle autonomous driving. In many cases this was caused by a sharp leap in the development of intellectual transport systems at the turn of the first two decades of the 21st century. However, until some significant problems are solved talking about the widespread appearance of autonomous vehicles is premature. The purpose of the work is to formulate the main problems arising in the transition to the higher levels of automation. The article lists three main problems which are to be solved while implementing autonomous vehicle driving: legal (responsibility for road traffic accidents), technological (adaptability of algorithms, self-organization and survivability of the driving system) and social (hedonistic approach to driving). The author calls the widely spread application of mobile gadgets one of the main social problem and notes the negative impact of this phenomenon on the level of road safety in the country. The transition to fully automatic control seems to be the only possible solution to this problem. Modern classifications of automation levels have been considered and a number of remarks was made concerning them. The author developed a new classification of driving paradigms depending on the kind of signal between the elements of the system “driver - vehicle - road - objects - environment” (DVROE), which included traditional, active, intelligent, remote, autonomous and isolated control. The main problem arising in the transition to an autonomous and isolated level of automation is the adaptation of the driving process to the elements of the DVROE system. The author proposes some solutions to this problem. A diagram of the application of various control paradigms, depending on the automation level of the vehicle is suggested.

In the article the authors consider the vibration process, which occurs when the vehicle mechanical transmission is switched on. Oscillations arising at idle speed of the vehicle and associated with an engine bearing system defect or its gear knocking are not considered in this article. Vibrations that appear during the slipping of friction discs have been investigated. This phenomenon, known in the automotive industry as a “jerk” of the clutch, determines both the durability of the vehicle and its comfortability. Two reasons to cause the vibrations in transient operating modes were determined. One of the reasons was the self-oscillations of the friction discs caused by the change in the friction coefficient depending on the sliding speed. As an example, a model of a mechanical system describing the causes of arising oscillatory processes was considered, and recommendations for their elimination were given. The second reason for the occurrence of clutch “jerks” was accounted for by the deviations in the geometric dimensions of the structural elements. The narrowing of production tolerances of parts and the control of accuracy during assembly made it possible to reduce the likelihood of oscillations. However, the best technical solution should be found at the early stages of the vehicle design, since the separate optimizing of the coupling design would not result in a technically and economically feasible effect. The task to reduce the vibration load on the vehicle requires a comprehensive consideration. The article also proposes the scheme of the vehicle dynamic system. The development of the model will allow to determine the natural frequencies of the system, to reveal the resonance modes of operation and to find the maximum amplitude of the inertial masses oscillations, thereby reducing the time, labor and materials costs to carry out a large amount of full-scale experimental and finishing work at the design development stage. The result of the research is the developed recommendations necessary for predicting and ensuring the vibration resistance of the vehicle against the “jerk” of the clutch.

The article considers the modern problems of atmosphere pollution in the large cities. The official discussion of a new urban air pollution problem put forward by the Russian Federation has been analyzed. The new problem was caused not only by the gas exhausts but by the wear of tires and roads surface.The quotations from speeches made by the representatives of different countries and organizations were cited and analyzed. The authors came to a conclusion that in the environment the particles of worn tire treads did not exist in isolation. In fact, they were always mixed with at least pavement particles, thereby reducing the rubber weight in the solid fraction. It was stressed that the choice of methods used for the detection of particles was also an acute problem. The comparative materials of the research carried out at FSUE “NAMI” on the values of PM 10 and less emitted by vehicles in urban conditions on the example of the city of Moscow were given as well as the forecast estimation of their exhaust up to 2030. The studies showed that solid particles emissions caused by worn tires and braking systems were nowadays 10 times greater than the solid particles emissions made by diesel engines when compared to Euro-6 standards adopted in Europe. On the basis of the materials presented in the article, it can be stated that there is a serious problem that has not been given attention before - the pollution of the urban air environment by products of tire wear and brake mechanisms, leading to the formation of smog in major European cities.

The complexity of determining the internal combustion engine (ICE) power level, in general, and the use of a flywheel power energy, in particular, makes it necessary to evaluate and take into account a large number of probabilistic objective and subjective factors in traffic conditions. A vehicle with a combined power unit (CPU) has an additional unit that presents a problem - a stored flywheel energy with a stepless variable drive and with a specific algorithm of connection to the transmission. The productivity of a transport vehicle is characterized by an average speed of motion, which depends on the probabilistic external environment impact, determined both by the objective motion conditions and subjective environment factors. The external impact of the environment (road or off-road) on the transport vehicle is represented by a vector with random components that have stationarity and ergodicity properties. Comparative characteristics of such systems based on the average speed of movement were given by using the developed technique of statistical modeling of external disturbances affecting a conventional or CPU vehicle equipped with an ICE and a flywheel of stored energy. The effect of the energy capacity of the flywheel and, in particular, the setting power of the stepless hydrostatistic-mechanical drive of the CPU on the average speed of the vehicle with a mechanical transmission and the loading of the ICE was assessed. The factors limiting the speed of the transport machine and their impact on the effectiveness of the investigated system in motion were studied and determined. The obtained results allowed to determine and optimize the parameters of the CPU with the flywheel energy storage.