• TRANSPORT TECHNICS. INVESTIGATION OF ELEMENTS. RELIABILITY

    Experimental Results of the Hybrid Electric Vehicle Energy Efficiency in Urban Transportation

    Trans Motauto World, Vol. 6 (2021), Issue 2, pg(s) 43-46

    The development of internal combustion engine vehicles, especially automobiles, is one of the greatest achievements of modern technology. Automobiles have made great contributions to the growth of modern society by satisfying many of its needs for mobility in everyday life. The automotive industry and the other industries that serve it constitute the backbone of the word’s economy and employ the greatest share of the working population. However, the large number of automobiles in use around the world has caused and continues to cause serious problems for the environment and human life. Air pollution, global warming, and the rapid depletion of the Earth’s petroleum resources are now problems of paramount concern [1]. A hybrid vehicle combines any type of two power (energy) sources. Possible combinations include diesel/electric, gasoline/fly wheel, and fuel cell (FC)/battery. Typically, one energy source is storage, and the other is conversion of a fuel to energy. The most modern hybrids are powered by a combination of traditional gasoline power and the addition of an electric motor. However, hybrid still use the petroleum-based engine while driving so they are not completely clean, just cleaner than petroleum only cars. This enables hybrid cars to have the potential to segue into new technologies that rely strictly on alternate fuel sources [2,3].
    This paper considers the experimental result obtained from HEV energy efficiency researching in urban transportation in the town of Sofia.

  • MECHANIZATION IN AGRICULTURE

    Theoretical and methodological features of soil water regime optimization in pedagogical technologies of agroengineers training for innovative project activity

    Mechanization in agriculture & Conserving of the resources, Vol. 66 (2020), Issue 5, pg(s) 157-162

    Innovative scientific-technical and pedagogical bases of studying in higher education institutions by future specialists in agroengineering of the theory and calculation fundamental questions of sprinkler nozzles and devices of machines for irrigation of agricultural crops are presented. Some constructive schemes of nozzles, namely, deflector, crack, etc. are analyzed. Graphs for determining the range of the jet and determining the rational shape of the nozzle are given. It is proved that all this can be effectively applied both in the educational process during the study of agricultural machinery and equipment by students and in research and production practice. Depending on the purpose, tasks, methods of technological processes of irrigation disintegration of a water jet on drops is analyzed. An algorithm for calculating the working bodies of sprinklers is presented, it can be used by agricultural engineers during their design activities. It is established that it is effective when students first study and analyze the state of agricultural production, for example, during internships, identify shortcomings of technological processes, opportunities for improvement, level of technical support, and then, using theoretical knowledge, mastered methods of engineering calculations, design and construct working bodies of sprinklers. Formulas for determining the radius of the irrigation sector, the maximum angle of the rocker arm at which the nozzle is attached, the total travel time of the rocker arm in both directions, the speed of the liquid in the jet and more are given. The methodological features of functioning of various designs of nozzles of sprinklers are theoretically described. The results of scientific research presented in the article can be used as didactic material in lectures, during laboratory-practical classes, independent work of students, as well as graduate students and scientists at the stage of design and construction of reclamation machines. The main theoretical provisions are recommended to be included in the list of test tasks for assessing the readiness of agricultural engineering for innovative project activities. It is noted that the study of the basics of designing the working bodies of irrigation machines is one of the factors of a holistic conceptual system of protection of soils and water resources. Emphasis is placed on the fact that soil and water resources are important objects and prerequisites for the development of reclamation machines and the formation of special design competencies of agricultural engineers

  • VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY

    Methodology for static tuning of the HEV fuel flow measuring system

    Trans Motauto World, Vol. 5 (2020), Issue 1, pg(s) 30-33

    The modern automobiles are subject of more stringent requirements [1] corresponding to power, torque, fuel economy and ecology legislations, which is led to designing of new power sources and constructions, such as the hybrid electric vehicles (HEV). They are moving by the energy [2], which is ensured by the internal combustion engine (ICE) and the battery. The main factor in this area is the HEV fuel system, which is controlled by the electronic control unit (ECU) [1]. The electronic control of the Spark Ignition Engines (SI engines), as well as the Direct Ignition Engines (DI engines) is based on the certain sensors signals, program maps and management algorithms. The result in this electronic control is the management of the fuel injectors. The management of the fuel injectors consists in the start of injection, injection duration, number of injection events, injection advance, injection pressure etc. Moreover, the fuel consumption and fuel efficiency are the main factors, which are determining the HEV advances. The learning and measuring the HEV fuel consumption, as well as, the conventional automobiles, is the ground for achievement of quality results in the education of the automotive engineers, as well as for obtaining of scientific researching for developments and innovations. Significant meaning in this concept has the real, live and practical performance with the help of testing equipment and test-benches. This paper renders the methodology of static tuning the Fuel Flow Measuring System EFMS100 on the test bench SAV-1 with the support of controller Matrix MIAC MI0245 and Flowcode 7 software.

  • MECHANIZATION IN AGRICULTURE

    Soil and water resources as important objects and prerequisites for the design of agricultural machines and the formation of professional competencies of an agricultural engineer

    Mechanization in agriculture & Conserving of the resources, Vol. 65 (2019), Issue 4, pg(s) 120-125

    The scientific, technical and pedagogical bases of studying issues of soil and water protection by future specialists in agro-engineering in of higher education institutions are presented. Some concepts and categories that are used in the educational process for students to study agricultural land reclamation machinery and equipment are analyzed. Depending on the purpose, tasks, techniques of technological processes, the types of land reclamation measures are distinguished. The example of calculation of working bodies of earthmoving reclamation machines is given. According to the developed innovative studying technologies, students first study and analyze the state of agricultural production, identify the disadvantages of technological processes, the level of technical support, and then, using mathematical apparatus, methods of engineering calculations design and construct a reclamation machine. The methodological features of calculating the power balance of the earth-moving reclamation machine, which includes the power required to: isolate the material to be processed, taking into account its deformation, are theoretically described; the movement of the material being treated, that is, providing it with kinetic energy; lifting of the processed material; overcoming the friction resistance of the treated material against the surface of the working body and guide surfaces; overcoming the full resistance of the movement of the machine, taking into account the slope of the surface of the movement to the horizon; overcoming the propulsion of the propulsion; acceleration of the machine to the calculated speed of movement (overcoming the forces of inertia); drive conveyors and accessories. The developed procedure of laboratory and practical work includes the study of the methods and features of the calculation of balance capacity components of reclamation machines, taking into account such indicators as the type of soil, its density, thickness of layer, productivity, kinematics of the working body, the required lifting height, etc. The lecturer must draw up a general report on the theoretical and practical part of the laboratory and practical work in accordance with his task and protect it from the faculty of the department. The developed pedagogical technology of cross training emphasizes that soil and water resources are important objects and prerequisites for the development of agricultural machines and the formation of design competencies of agricultural engineers.

  • Solidification in small volume

    Materials Science. Non-Equilibrium Phase Transformations., Vol. 4 (2018), Issue 4, pg(s) 142-145

    Model results of solidification processes as a bridge between individual sciences are presented. There is a historical analysis of the development of knowledge and methodologies in different sciences. A methodological scientific approach has been used. It is proposed to develop known scientific methodologies with the expansion of new results. Representations are modeling results in low volume solidification. These tasks are convenient in a mathematical description of an additive approach.

  • Methodology and results of experimental studies of combined unit for sugar beet tops harvesting on the basis of a row-crop tractor

    Mechanization in agriculture & Conserving of the resources, Vol. 64 (2018), Issue 5, pg(s) 158-161

    On the basis of an integrated wheel-type tractor (traction class 3.0), there was created the new combined machine and tractor unit carried out a continuous flat cutting of the sugar beet tops with a front mounted sugar beet tops cutting machine. To carry out this field experimental studies, a program and methodology was developed based on measurements of the remains of the tops on the heads of root crops after passing through the aggregate at a given rate of translational motion, the height of the installation of its rotary cutting mechanism above the level of the soil surface and the frequency of its rotation. The results of the study were statistically processed on a personal computer using regression and correlation analysis methods. Based on the developed methodology of the full-factor experiment, empirical mathematical models were constructed in the form of regression equations for the process of cutting the tops of sugar beet. According to the results of these calculations, it was found that the speed of the forward movement of the sugar beet tops cutting aggregate exerts the greatest influence on the mass of the remains of the tops on the spherical surfaces of the root heads, after a continuous main cut. In a lesser extent, this process is influenced by the rotational speed of the rotor of the sugar beet tops cutting machine and the height of the rotor installation above the soil surface level by means of two pneumatic copying wheels. According to the results of experimental studies, it has been established that the rational design and technological parameters of the process for harvesting sugar beet tops by a front mounted sugar beet tops harvesting  machine with a rotary cutting apparatus is its rotation frequency equal to 960 rpm, the speed of the aggregate should not exceed 2.0 m.s-1, and the height of the rotor installation should be as low as possible, not less than 0.02 m.

  • Protection of soils and water resources as an important factor in forming preparation to the project activity of future agroengineers in institutions of higher education

    Mechanization in agriculture & Conserving of the resources, Vol. 64 (2018), Issue 4, pg(s) 141-145

    Here are presented the results of scientific researches on the study of the bases of protection of soils and water resources by future agroengineering specialists in higher education institutions. In the educational process of agroengineering training, it is important to develop a motivational and cognitive criterion of preparing the future specialists for the project activity on the basis of fundamental  knowledge of the mechanical and technological properties of agricultural materials such as soil, water, fertilizers, pesticides, plants, shrubs, trees, as well as other additional products and agricultural waste, etc., for the purpose of carrying out the necessary environmental measures that will ensure the optimization of the parameters of technological processes, machines and structures which are being developed, constructed and projected. Innovative pedagogical technology of teaching is developed according to the method of gradually increasing the amount of educational material, which comes as a result from previously learned and mastered material. It is recommended that about 20% of the training program for agroengineering to be directed by obtaining general and special environmental competencies. The acquired special professional skills of agroengineers will ensure the development of project activity on the basis of preservation and multiplication of natural resources.

  • TRANSPORT. SAFETY AND ECOLOGY. LOGISTICS AND MANAGEMENT

    LINE TRACK CAPACITY – ANALYSIS OF THE IMPLEMENTATION OF THE UIC 406 METHODOLOGY IN ŽSR CONDITIONS

    Trans Motauto World, Vol. 3 (2018), Issue 4, pg(s) 181-184

    A variety of A variety of methodologies are used across Europe for the estimation of railway infrastructure capacity. This paper introduces the basic principles of the analytical methodology (e.g. Slovak railways) and UIC methodology. On the basis of these new approaches, dependencies between occupation time and buffer time is researched. The aim is to compare the needed buffer time and its impact to the line capacity.

  • INTENSITY OF SOLIDIFICATIONI

    Materials Science. Non-Equilibrium Phase Transformations., Vol. 4 (2018), Issue 1, pg(s) 23-26

    The identification of the heat exchange intensity at the work surface of the mold is defined by the base information of the type and movement of the solidification front. Parameters and their influence are shown on the type and movement of the solidification front: initial melt temperature; initial temperature of the mold; the ceramic coating on the work surface of the mold; distribution of the mass of the mold. The methodological link of these parameters is shown in the creation of each casting technology.

  • MECHANIZATION IN AGRICULTURE

    DETERMINATION OF THE LIQUIDITY VALUE OF AGRICULTURAL AND FORESTRY EQUIPMENT

    Mechanization in agriculture & Conserving of the resources, Vol. 63 (2017), Issue 6, pg(s) 239-241

    The structure of production in agriculture is changing with the change of priorities, both at EU and national level. On the one hand, this is due to interconnection in individual sub-branches, on the other, to the replacement of traditional technologies with new ones. In both cases, this requires the maintenance of more equipment than is necessary for production and the corresponding increase in the cost of production and the reduction of the profit from production. Significant lagging of the machine-tractor fleet renewal processes and increased loading of the used equipment imply intensive physical wear and obsolescence.

    Depending on the reasons for write-off, when determining the liquidation value of the machinery, account shall be taken of special features and the possibilities for further use of individual elements (parts, assemblies and aggregates). Several approaches are used to determine the liquidation value:

    – the whole machine is considered scrap. The approach is applicable to working machines and attachments to self-propelled agricultural machinery;

    – the whole machine is classified as scrap but is dismantled and divided according to the type of scrap (ferrous and non-ferrous metals). The approach is applicable to retractors and attachments to self-propelled agricultural machinery as well as stationary machinery for primary production processing;

    – the machine is rated as scrap of ferrous and non-ferrous metals and second-hand spare parts. The approach is only applicable to physically worn machines.

    In addition to that, an improved methodology for assessing the liquidation value of different groups of agricultural machinery for moral and physical extinction with and without residual resource elements is suggested.

  • TRANSPORT. SAFETY AND ECOLOGY. LOGISTICS AND MANAGEMENT

    METHODICAL ASPECTS OF DETERMINING THE PROFITABILITY OF THE RAILWAY ROLLING STOCK OPERATOR

    Trans Motauto World, Vol. 2 (2017), Issue 6, pg(s) 238-240

    This article analyzes and comparison of the various scientific and methodological approaches to determining the profitability of rolling stock operated by operating companies. We consider four different methods of profitability calculation, carried out their comparison revealed the advantages and disadvantages of each method. Recommendations on the field of application of each method.

  • TECHNOLOGIES

    CALCULATION OF TRANSPORT DEMAND BY APPLYING SOFTWARE PACKAGE PTV Vision VISUM

    Machines. Technologies. Materials., Vol. 11 (2017), Issue 3, pg(s) 134-136

    The contemporary lifestyle leads to rapid increase of number of motorized traffic participants thus, there is a need of traffic planning. The task of any modern traffic planning is creating such road network that will be reviewed, safe, with appropriate capacity, economical in terms of exploitation costs and cost for building, also designed to be compatible with structure of the city. In the field of traffic engineering exist a wide range of software packages for different purposes, with different performance and quality. One of them is world leading software package for traffic analyzes and forecast of transport demand, PTV Vision VISUM.

    In this paper will be represented the steps of the methodology for calculation of transport demand, starting from setting the background, drawing the traffic network until the forecast using an appropriate software package PTV Vision – VISUM in which the base is standard four step transport demand model.