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Trudy NAMI

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No 2 (2023)
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ENGINE DEVELOPMENT

6-17 210
Abstract

Introduction (problem statement and relevance). In addition to the toxic substances generated during fuel combustion in the engine, the vehicle generates a significant amount of hydrocarbons in the form of fuel vapors generated as a result of evaporation from the fuel tank and fuel system components. The evaporation process parameters and the amount of fuel evaporations are determined by dynamics of fuel heating in the tank in various vehicle operation modes. Modern requirements for the limit level of emissions caused by evaporation become much stricter. Therefore, the solution of the task of fuel evaporation minimization and prevention of ingress thereof into the atmosphere is relevant and practically significant. The purposes of the studies are to develop a model of the processes of evaporation generation in the vehicle fuel tank based on the analysis of mathematical modeling and experimental research results as well as to develop the optimum strategy and algorithm of the canister feed.

Methodology and research methods. In the study, a combination of analytical methods of the classical thermodynamics with modeling in the Simcenter Amesim integrated program platform environment is used.

Scientific novelty and results. It has been found that transition from feeding the canister with an open vapor space to evaporation in a fixed-volume space allows significant reduction of the amount of hydrocarbons delivered to the canister.

Practical significance. It has been found and proved that accumulation of hydrocarbons in a closed tank with discrete cyclic feed of the canister allows significant reduction of evaporation generation and lowering of the requirements for the canister parameters. An algorithm of optimum canister feed is suggested.

18-30 139
Abstract

Introduction (problem statement and relevance). The oxidation catalysis provides the necessary efficiency and performance of diesel filters for trapping dispersed particles and systems for selective treatment of nitrogen oxides. In addition, oxidation catalysts can be a tool for neutralizing emissions of methane and some non-regulated but very hazardous polycyclic and partially oxidized hydrocarbons. There are also poorly studied theoretical issues of oxidation catalysis associated with mutual influence of toxic components contained in exhaust gases of diesel engines.

The purpose of the study is to clarify the oxidation catalysis role in the general problem of after-treatment of toxic emissions of diesel engines, development and testing of catalysts and converters for neutralization of toxic combustion products of engines powered by natural gas.

Methodology and research methods. Research into the catalysts under flow conditions using modern methods of gas analysis, IR spectroscopy, engine tests of the developed catalytic converters.

Scientific novelty and results. The paper shows the role of oxidation catalysis in solving the common problems of after-treatment of hazardous emissions of diesel engines including both direct after-treatment of toxic compounds and supporting functions. Catalysts of higher efficiency and a series of converters for gas engines have been developed. Innovative methods to increase the resistance of oxidation catalysts to sulfur oxides have been proposed.

Practical significance. The developed catalysts and converter designs are recommended for implementation in KAMAZ-820.52-260 and Cummins 250 and 280 gas engines.

31-41 138
Abstract

Introduction (problem statement and relevance). Improvement of environmental parameters of internal combustion engines is one of the most relevant tasks of the domestic transport engineering. Calculation support allows reducing the time and raising the efficiency of works for refining of the bench work process in order to meet the required parameters. The paper is devoted to development of a two-dimensional calculation model for hazardous substances formation in combustion products of spark-ignition engines based on the non-equilibrium kinetic models of formation of nitrogen oxides and carbon monoxide.

Methodology and research methods. Computational methods for differential equations (ordinary and partial ones) are applied. Non-equilibrium kinetics of hazardous substances formation in combustion products is considered. The work process is calculated based on a combination of the mesh control-volume method and determination of the observable flame rate based on the experimental data (taking into account the development stage of the flame source).

Scientific novelty and results. The new calculation method for flame propagation in the spark-ignition engine is suggested. The developed model combines such advantages as good predictability and short time of calculation.

Practical significance. The model can be applied, in particular, to preliminary planning of three-dimensional calculations of the work process or their check in the absence of experimental data (at the stage of preliminary/concept design). The calculation results can be used as initial data for modeling of the exhaust gas aftertreatment (additional purification) system.

AUTOMOBILE DEVELOPMENT

42-59 223
Abstract

Introduction (problem statement and relevance). Currently, mobile driverless transport and technological means are widely used for automation of work processes and remote control over a vehicle, excluding immediate human attendance in dangerous areas. Generally, such vehicles feature an electric powerplant while using batteries as energy storage devices. In order to reduce the number of operations during such vehicle driving, it is convenient to use a running gear design that is symmetric relative to its longitudinal and transverse planes. Reducing energy consumption will allow increasing in energy efficiency when performing transport and other technological operations. One of the ways to improve energy efficiency is to reduce the weight of elements of such vehicles. This can be achieved by using materials with high specific strength, such as aluminum alloys, and by developing optimum loading patterns for such element structures. The object of the study is a driverless 4x4 vehicle with the fully loaded weight of 830 kg. The research subject is the methods of optimum designing of vehicle load-bearing structures and their use taking into account the operating conditions. The purpose of the study is to develop the methodology for designing suspension elements for a vehicle with a symmetric design of the running gear made of aluminum alloy taking into account the loading modes.

Methodology and research methods. The paper presents a dynamic mathematical model of the wheeled vehicle for determination of loads created in a program for rigid bodies dynamics modeling, the methodology for bringing the loads to one suspension unit (front left wheel), loading patterns for suspension elements obtained with the use of topological optimization and strength calculations performed with application of the finite element method confirming the design functionality.

Scientific novelty and results. The paper presents the method for bringing the loads obtained for all suspension elements to the front left point, since the driverless vehicle has a symmetrical running gear design. Taking this into account, a rigid-body dynamic model and an algorithm for processing the obtained loads for a finite element model were developed. Also, typical modes of vehicle loading were selected. The loads were distributed among the following types: operational, extreme and emergency ones. Recommendations were given for the choice of restrictions when conducting topological optimization depending on the mode type. As a result, loading patterns for suspension guiding device elements were obtained. Check calculations were carried out to confirm the design functionality.

Practical significance. The obtained results can be used in development of highly loaded elements of wheeled vehicles.

REVIEWS, ANALYTICS

60-72 114
Abstract

Introduction (problem statement and relevance). Today's scientific papers on hydrodynamic torque transformers are related to the topic of optimising their design in order to decrease the cost of manufacture with improvement or insignificant degradation of transforming properties and fuel economy at the same time. However, no attention is paid to the issue of building rational model ranges of hydrodynamic torque transformers.

The purpose of the study is to analyze the existing approaches to development of model ranges of hydrodynamic torque transformers and to search for criteria for development of a higher-quality calculation method.

Methodology and research methods. The study was carried out by comparing the model ranges of hydrodynamic torque transformers in question produced by various manufacturers and defining the common parameters applied to classify models in a model range.

Scientific novelty and results. As a result of the analysis of model ranges of hydrodynamic torque transformers and existing methods of development of model ranges of hydrodynamic torque transformers, classification of approaches to their development has been carried out. Recommendations were also given regarding the parameters to be considered when developing model ranges of hydrodynamic torque transformers.

The practical significance consists in the systematization of information about the model ranges of hydrodynamic torque transformers of different manufacturers. It is shown that building model ranges of hydrodynamic torque transformers according to the known methods does not take into account correspondence of their key parameters with the characteristics of the range of internal combustion engines applied together therewith. The paper offers the approach, which takes this aspect into account.

73-83 271
Abstract

Introduction (problem statement and relevance). Reduction of greenhouse gas emissions and energy consumption related thereto (energy efficiency) for vehicles is a part of the global problem of reduction of human impact on climate change and saving natural resources. As a member of the global community, the Russian Federation takes part in relevant international agreements and treaties. This scientific paper offers a detailed analysis and expert opinion regarding the main existing approaches aimed at electric vehicle (EV) cruising range extension, also taking into account the experience accumulated in the Russian Federation.

The purpose of the study is to analyze international and domestic experience in design and development of EVs having an extended range per charge.

Methodology and research methods. The methods used are based on the fundamental principles of the theory of vehicles, vehicle automated systems, as well as fundamental principles of electronics and electrical engineering, research test methods.

Scientific novelty and results. The analysis of electric vehicles (EVs) development through synthesis of approaches to extend the cruising range on a single charge was carried out. The analytical and expert assessment of the approaches to extend the EV cruising range on a single charge is proposed.

The practical significance consists in the results of scientifically based synthesis of approaches to extend the EV cruising range on a single charge. The obtained results and recommendations are aimed at improving energy efficiency of vehicles as well as promoting EVs in the Russian Federation.

84-102 233
Abstract

Introduction (problem statement and relevance). The territory of our country is located in the area with periodic snow cover. There is a great variance in duration of snow cover, its nature and properties among different regions of the country. The Far North snow cover lasts for 10–11 months. To develop the territory of Siberia, Altai, the Far East and the Far North, as well as to solve the issues of energy, technological and economic security, there is a need for vehicles having high passability or off-road performance in a wide range of driving conditions. Despite intensive road construction and growth of the road network, provision of transport accessibility for the far regions of our country continues to be a relevant and prospective task for the automotive industry. The article considers scientific and practical approaches and results of the studies conducted by the Special Design Bureau of the Automotive Plant n.a. Ivan Likhachev (hereinafter – SDB ZIL) led by Vitaliy Grachev and focused on creation of ultrahigh-passability vehicles.

The purpose of the study is to review and to analyze the high-passability and ultrahigh-passability land vehicle designs made based on the studies conducted in the SDB ZIL for severe driving conditions (deep snow, water, swamp, sand, engineering obstacles).

Methodology and research methods. The article presents the analysis of the results of scientific and practical experiments in driving vehicles with both conventional – wheels and tracks – and non-conventional – rotary screw, pneumatic roller and other – running gears in different environments, which were obtained using the methods proposed by Vitaliy Grachev.

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 off-road conditions, as well as reliable design and engineering solutions proven by practical implementation of successful projects.

Practical significance. Restoring the belief in capabilities and potential of the Russian scientific and engineering school by informing the new generation of engineers about the achievements and successful projects by the SDB ZIL led by Vitaliy Grachev related to creation of wheeled vehicles and vehicles with non-conventional running gear types (rotary screw and pneumatic roller tracked running gears) in different environments, as well as about the scientific and practical methods used in their implementation.



ISSN 0135-3152 (Print)