Introduction (problem statement and relevance). Improvements of designs and performance indicators of internal combustion engines (ICEs) and motor vehicles (MVs) are constantly ongoing. Modern vehicle ICEs comply with the UN Regulations. However, an important task is to extend the ICE service life while increasing the maintenance intervals, and to significantly reduce the total particulate matter (PM) emissions into the atmosphere caused by MV operation and containing invisible cancerogenic compounds especially dangerous to the health of the population.

The purpose of the study is to determine the root causes influencing the maintenance intervals with respect to the engine oil ageing indicators.

Methodology and research methods. The study included analysis of cancerogenic PM emissions with ICE crankcase gases and their possible influence on oil ageing decreasing the maintenance intervals. Scientific novelty and results. The study determined and assessed the level of total emissions of cancerogenic PM from various vehicle units: from the engine, from brake pad wear, from tyre wear, as well as emissions from uncontrollable wear of asphalt-concrete and gravel roadway.

Practical significance. The results obtained regarding emissions of cancerogenic PM of various origin during long-term operation of motor vehicles prove low environmental efficiency of the recommendations given in the Paris Climate Accords (2015) concerning replacement of modern ICEs with electric drive power trains and replacement of conventional fuels with hydrogen. Since the main dangerous sources of urban atmosphere pollution that are dangerous to the health of the urban population still remain the same – namely, the products of asphalt-concrete, gravel roadway and tyre wear, which today make 80% of total PM emissions. Recommendations on double reduction of emissions of PM with cancerogenic substances dangerous to the health of the population have been developed.

This is the second part of the research work under the general title “On fuel and deposits” devoted to study of peculiarities of deposit formation in the internal combustion engine (ICE) and to the role of fuel in this process. The fact that the group composition of gasoline, especially the presence of olefinic and aromatic hydrocarbons (HCs), significantly affects the intensity of both “cold” and “hot” deposits is known and described by many researchers. The authors just contributed the results of their research to this fund having analysed the interrelation of physical and chemical properties of components of the main HC groups that make up the fuel compositions of gasoline and diesel fuels – alkanes (paraffins), cycloalkanes (naphthenes), arenes (aromatic HCs) and alkenes (olefins). Experimental studies of specially prepared gasoline devoid of the olefin component have been performed. The result was somewhat unexpected – the intensity of deposits on the intake valves had reduced fivefold. To some extent, this exonerates aromatic HCs from “the charge” that they are the main “supplier” of building material for formation of deposits on the intake valves. At the same time, it has been shown that the mass of deposits in the chamber was approximately the same when the engine was running on the base and olefin-free gasoline. Therefore, this clears olefinic HCs of the “suspicion” that they are responsible for the carbon residue formation in the combustion chamber, and makes it reasonable to think that it is aromatic HCs that are the “supplier” of building material for formation of carbon residue on the pistons and walls of the combustion chamber.

Introduction (problem statement and relevance). There is some significant potential for radialaxial turbine efficiency increase at the initial design stage, namely the center line of fluid flow calculation, due to the fact that the impeller machine appearance is formed and its main shape and dimensions are determined at this stage. Traditional approaches to optimization of a radial-axial turbine at the stage of center line of fluid flow calculation assume introduction of auxiliary variables or simplification of the initial system of equations.

The purpose of the study is to develop a numerical algorithm for searching optimal parameters of a radial-axial turbine at the stage of center line of fluid flow calculation using numerical optimization methods; comparison of the results obtained using the numerical algorithm with the results of optimization performed on the basis of traditional approaches.

Methodology and research methods. Formalization of radial-axial turbine center line of fluid flow calculation in the form of a nonlinear programming problem. Solving the nonlinear programming problem using numerical optimization methods.

Scientific novelty and results. Constrained nonlinear optimization of parameters of a radial-axial turbine at the stage of center line of fluid flow calculation and its subsequent software implementation.

Practical significance. Improving accuracy and reducing time of search for the optimal solution at the stage of radial-axial turbine center line of fluid flow calculation.

Introduction (problem statement and relevance). The article shows experimental studies of vehicle vibroacoustic (NVH) characteristics focused on identification of oscillation sources and their contribution to noise and vibration measured in the reference points within the vehicle, as well as analyzes the oscillation propagation paths.

The purpose of the study is to develop recommendations for improvement of vibroacoustic characteristics of transport and technological vehicles, appliances and facilities by the example of a vehicle based on studies of oscillation sources and their contribution to noise and vibration measured in the reference points within the vehicle, and oscillation propagation paths.

Methodology and research methods. Vehicle vibroacoustic characteristics study. Determination of oscillation sources and their contribution to noise and vibration measured in the reference points inside the vehicle. Oscillation transfer paths study.

Scientific novelty and results. The result of the studies is the recommendations developed to improve vehicle vibroacoustic characteristics and the developed algorithm allowing conducting comprehensive studies of vehicle vibroacoustic characteristics. The scientific novelty consists in comprehensive studies of vehicle vibroacoustic characteristics based on the studies of vehicle internal noise and vibrations in operating modes, overall noise and vibration level analysis, as well as studies of the transfer functions from the oscillation sources to the reference points, the paths of propagation of oscillations from the sources to the reference points and analysis of the developed modal chart of the vehicle.

Practical significance. The vibroacoustic studies algorithm has been developed, according to which comprehensive studies of vibroacoustic characteristics of transport and technological vehicles, appliances and facilities are performed by the example of a motor vehicle. The research results can be used in scientific, research, educational institutions and manufacturing enterprises specializing in development and production of motor vehicles as well as in studies of vehicle vibroacoustic characteristics.

Introduction (problem statement and relevance). The given paper justifies the relevance and describes the process of creating a roller bench for motorcycle and power product fatigue endurance testing. The purpose of the study is to create a roller bench for motorcycle and power product load-bearing structure fatigue strength testing; to develop individual components of the test bench; to analyze the recorded signals during mode metering and during the process of single roughnesses initialization; to test a solo motorcycle on the test bench.

Methodology and research methods. When designing the test bench, Russian and foreign test procedures for motorcycles and automobiles were studied, as well as different patents, articles and papers.

Scientific novelty and results. In order to determine the main parameters of the future roller bench, motorcycle mode metering was performed so as to assess the bearing structure loading when riding through the proving ground roads with special pavements. Further, the selection of the main bench parameters is justified, such as the range of trail and wheelbase of the object under test, diameters of the rollers and method of their rotation rate measuring, dimensions, geometry and number of obstacles, drive power, etc. A system of motorcycle ballasting and holding on the bench is designed. Potential errors when designing similar test benches are shown, their solutions are suggested. Statistical and spectral analysis of motorcycle loads recorded at the FSUE “NAMI” Testing Center proving ground was performed, and, based thereon, selection of single roughnesses for bench testing was made.

Practical significance. As a result of the conducted research, a roller bench, on which a motorcycle is currently being tested, was designed and manufactured. A foundation has been laid for methodical transition from road load tests to bench tests.

Introduction (problem statement and relevance). The studies aimed at vehicle passive safety improvement have been conducted since the middle of the 20th century. In order to determine the consequences of road accidents, anthropomorphous testing devices – dummies – are used. Besides actual or field testing for vehicle design preliminary assessment, virtual testing implemented by means of the finite-element method is conducted. The issue of development of the dummies finite-element models showing physical behavior and high accuracy of the results obtained at simulation is relevant for the domestic automotive industry development, since only free of charge models, which do not comply with the specified requirements, are available to the engineers at this time.

The purpose of the study is description of the phased plan to form the procedure of dummy finite-element model development.

Methodology and methods. The papers devoted to development of the dummies and their mathematical models and development of the dummies models and their validation have been reviewed.

Scientific novelty and results. The paper shows the basic issues arising at virtual testing simulation using the dummies. The scientific novelty consists in justification of necessity to arrange a domestic study to perform vehicle virtual testing for passive safety.

Practical significance. Considering the issue specified in this paper, studies aimed at development of domestic finite-element models of the dummies can be conducted.

Introduction (problem statement and relevance). With the high competition for specific parameters, electrified vehicle manufacturers are making great efforts to create powerful and compact components. One of such solutions is the axial flux electric motor, the specific power of which is claimed by many companies to be over 6 kW/kg. Developments of such top companies as Whylot, YASA, AVID, Beyond Motors, Phi-Power only confirm the promising potential of this research trend.

The purpose of the study is to investigate the thermal state of the axial flux electric motor and determine the heat transfer coefficient of alternative heat exchangers with lower hydraulic resistance.

Methodology and research methods. The methods used are based on the fundamental principles of electronics and electrical engineering, hydrodynamics and heat transfer, methods of research testing and engineering analysis.

Scientific novelty and results. Development of electric motors with high specific power of more that 6 kW/kg is considered to be promising, while cooling remains the main problem. According to the research results, a 3D model of the electric motor heat exchanger is obtained, which most satisfies the given requirements.

Practical significance. Due to continuous increase in power density of this type of electric motors, it is necessary to improve the cooling efficiency. This paper is aimed at solving the issue of determining geometric parameters of the heat exchangers for the electric motors.

Introduction (problem statement and relevance). In recent years, electric vehicles sharply gained extra attention as an alternative to internal combustion engine (ICE) vehicles. The main driving forces for the transition to electric vehicles are said to be environmental protection and decreasing reserves of hydrocarbon fuels. With this motivation in mind, the parties to the Paris Agreement (2016) formed the strategic goals, among which was complete decarbonization of energy and transport by 2050, also through replacing ICEs with electric propulsion. In order to reach such an ambitious target while considering the size of the global and Russian vehicle fleets, serious financial, technological, material and social resources are necessary. The article attempts to assess the current level of Russia’s raw material base required for motor vehicles decarbonization, and the degree of its readiness to reach the Paris Agreement goals. The article consists of two parts. The first part considers the Russian automotive industry energy security during its transition to electric driving, while the second part studies the availability of the most problematic units and materials to implement such a solution.

The purpose of the study is to analyze the Russian raw material base situation from the perspective of its readiness for complete or step-by-step replacement of ICE powertrains with electric drives, including hydrogen ones.

Methodology and research methods. Analysis of information about production and usage of the main raw material resources required for manufacturing and operating electric vehicles in Russia.

Scientific novelty and results. There was no analysis of Russia’s raw material base from the perspective of its readiness for complete or step-by-step replacement of ICEs with electric propulsion carried out earlier. The resources in the form of necessary materials and electric energy that are available in Russia are insufficient for full-scale replacement of the existing ICE vehicle fleet with electric vehicles, both battery and hydrogen powered.

Practical significance. The revealed unpreparedness of Russia’s raw material base for replacement of ICE vehicles with electric vehicles makes it possible to exclude unjustified optimism regarding this solution, to evaluate carefully the prospects and fields of application of electric vehicles and to focus on finding more realistic ways to improve vehicle environmental characteristics and economic efficiency.

Introduction (problem statement and relevance). Currently, one can notice active development of municipal utility service vehicles with electromechanical transmissions. For a comprehensive analysis of characteristics of such vehicles having electromechanical transmissions they shall be evaluated after having done some effective work in the process of operation. The data obtained during the tests allow assessing the energy efficiency of the electric loader and revealing its advantages and strengths compared to diesel loaders.

The purpose of the study is to assess performance characteristics of a MEP-1000 electric mini-loader that underwent testing in the municipal utility service of Moscow.

Methodology and research methods. The performance characteristics were analyzed using the miniloader on-board control system, CAN Wi-Fi telematic system, and ERA-GLONASS telematic system. Scientific novelty and results. The electric mini-loader performance characteristics results and assessment are provided, such as autonomous operation time, charging time, distribution of effective work performance time and on time, distribution of hydraulic equipment operation time and driving time, energy consumption, mileage, and charging strategy.

Practical significance. The performance characteristics analysis results will help in designing municipal utility service vehicles with electromechanical transmissions.

Introduction (problem statement and relevance). Ensuring transport accessibility of the furtherflung regions of Russia is a relevant and important task of the automotive industry. The Northern and North-East regions of Siberia and the Far East make up about 60% of the territory of Russia, or ca. 14 million km2, and are characterized by severe natural and climatic conditions. Nearly 80% of these territories, namely 11.1 million km2, are occupied by years long permafrost, and about 2.1 million km2 are occupied by tundra, with 30–40% thereof being swamps. Swampiness of the oil-and-gas-bearing forested areas of Western Siberia comes up to 50–70%. The depth of snow cover in North-West Russia reaches 1–1.5 m. There is a great variance in duration of snow cover, its nature and properties among different regions of the country. In the absence of any extensive network of paved roads, which is especially characteristic of Siberia and the Far East, an important parameter of vehicles is their passability, or off-road performance. To develop the territory of Siberia, Altai, the Far East and the Far North, as well as to solve the issues of energy and economic security of the country, there is a need for vehicles having high passability in a wide range of operational conditions. The article studies theoretical and practical approaches and results of research conducted by NAMI Cross-Country Vehicle Department (CCV Department) in order to create cross-country off-road vehicles, amphibious vehicles, snowmobiles and all-terrain vehicles.

The purpose of the study is to analyze the approaches and methods used by the CCV Department when creating cross-country vehicles for severe driving conditions (deep snow, water, swamp, sand, dirt soaked roads).

Methodology and research methods. The article presents analysis of results of theoretical and practical experiments in terms of driving vehicles with wheel, pneumatic-roller and track running gears in different road conditions and off-road.

Scientific novelty and results. The article offers solutions, methods and recommendations for selection of optimal types and kinds of running gears for operation under specific running conditions, as well as reliable design and engineering solutions proven by practical implementation of successful projects.

Practical significance. Confirming the ability and capabilities of the Russian science and engineering school by informing the new generation of engineers about the achievements and successful projects of NAMI CCV Department on creation of wheeled and tracked vehicles intended for driving in various road conditions and off-road, as well as about the theoretical and practical methods applied when implementing them.