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  • Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method
    132-138
    Views:
    288

    Nowadays, the automotive industry is focused on weight and size reduction. Main advantage of this weight and size reduction are improving the fuel economy. The specific fuel consumption of a vehicle can be improved through e.g. downsizing area of heat loss, if we focus on vehicle with weight reduction. Weight reduction can be done by replacing material or by changing the size (dimensions) of components. In the present work we have focused on Audi A6 muffler, troubleshooting and optimizing the muffler by changing pipe length of inlet and outlet, also by replacing the original mesh plate to porous pipe. Based on optimization, prototype has been built with the help of 3D design tool CATIA V5 and the calculations of transmission loss (TL) have been performed by MATLAB. Plane wave-based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for muffler designers. The principles of TMM for predicting the transmission loss of a muffler was used. Result of this present study of an existing muffler has been analysed and then compared with vehicle level test observation data. Noise level have been optimized for new muffler design. Other literatures were played significant rule for validate our results.

  • Application of Topological Methods in the Development of Vehicle Components
    67-75
    Views:
    213

    Many areas of the industry are characterized by continuous changes, which define new directions of development in product design. The development of computers and software, the spread of modern production tools and the development of material technology make it possible to expand traditional production technologies with modern processes. Integrated CAD systems have occupied their place in the product design and development process for decades, reforming classical design methods. Popular optimization procedures in integrated CAD systems, such as shape optimization, topological optimization and the new generative design process, provide effective solutions for design engineers in more and more industrial application areas. Experience shows that modern design methods can be used in many areas of industry. The appearance of metal powder printing and additive technology make it possible to test the designed prototypes or even to produce the final products. The following article aims to support the above with the help of a case study.

  • Thermoelastic Problems of Multilayered Spherical Pressure Vessels Subjected to Axisymmetric Loading
    106-115
    Views:
    259

    This paper deals with the linear thermoelastic analysis of functionally graded multilayered spherical bodies subjected to constant mechanical and thermal loading. The temperature field is arbitrary function of the radial coordinate, the material properties and the radial body force vary according to power law functions along the radius of the sphere. An analytical method is presented to calculate the displacements and stresses within the multilayered spherical body. The method is expanded to tackle the problem of spherical bodies made from radially graded materials with temperature dependent material properties. The results are compared to finite element simulations and other methods.

  • Simulation Aspects of the High Pressure Die Casting Process
    521-529
    Views:
    189

    High pressure die casting (HPDC) is a manufacturing process for producing accurately dimensioned, sharply defined, smooth or textured surface metal parts. It is accomplished by injecting liquid metal at fast velocity and under high pressure into reusable steel dies. Compared to other casting processes, die casting is at the top end of both velocity and pressure. The high velocity translates into a very turbulent flow condition. The process is often described as the shortest distance between raw material and the finished product.

  • Experimental Study on the Effect of the Geometry of Punching Tool on Clinch Joints
    154-158
    Views:
    221

    In this study the effect of the punching tool’s geometry on aluminum alloy clinch joints is analyzed by experiments. Based on FE simulations the tip radius and the cone angle of the punching tool is changed, and their effect was analyzed by microscopic investigations and single lap tensile-shear tests.

  • Kinematics and Control of a Planar Cable Robot
    88-95
    Views:
    226

    This paper deals with the kinematics and control of a planar cable robot [1], which is driven by four DC motors with gear. Cable robots are frequently used e.g., for the motion of cameras in sport halls and stadiums and also in high storage logistical systems [2]. Main goal of this research work is to design and build a test bench with low budget, which can model the motion of real life cable robots.

  • The Influence of the Boundary Conditions on the Buckling of Thin-walled Cans during Manufacturing
    41-50
    Views:
    198

    In this paper the effect of the boundary conditions on the stability of thin-walled aerosol cans under axial pressure is investigated. The main objective is to outline the main characteristics of this highly nonlinear mechanical problem and to present methods to simulate the buckling of cans with different boundary conditions. Due to the numerical difficulties coming from the contact between the can and different components of the machines, the effect of the different supports of the can is investigated on the crushing (or buckling) force at which the loss of stability occurs. The commercial finite element software Abaqus is used to solve the problems and to present the efficiency of FE codes in the design process of cans.

  • Simulation of an Operating Machine in Dust Chamber
    266-275
    Views:
    211

    Auxiliary equipment used in the automotive industry, such as generator, air conditioner, or starter, is often exposed to harsh conditions, for example splash water, frost, or serious dust load. Therefore, these auxiliary devices are intended to be prepared by the manufacturers to these conditions. The topic of this paper is a part of the analysis of the dust control of generators, which in principle is no different from the examination of other equipment. The flow around the generator and in the dust chamber was simulated by Ansys FLUENT.

  • Component Development Using Topological Methods
    54-62
    Views:
    224

    The article aims to briefly summarize the design aids which can be used nowadays, such as topology optimization and generative design, which are common in integrated CAD systems. A case study is used to present the results and comparisons provided by the previously mentioned methods.

  • Application of Additive Technology in Precision Casting
    43-56
    Views:
    326

    In this paper the surface of the prepared test specimens had been examined with light microscopy and surface roughness measurements. In order to improve the surface smoothness of PLA specimens, application of ethyl acetate was required. After this surface treatment, microscopic images were taken again. The melting and decomposition temperatures of the materials had been determined using derivatography. The chosen method was precision casting with gypsum molding. Also, the plaster molds had been burnt out according to the predefined melting and firing diagram. The measurement series shows that the samples produced by 3D printing can also be used in the field of precision casting. They provide greater freedom of design, more sophisticated pieces, and prototypes can be finished in a shorter amount of time.

  • CSR Reporting Practices of Hungarian Banks
    70-81
    Views:
    272

    The disclosure of information on the exercise of corporate social responsibility (CSR) is the tool most frequently used by companies to promote understanding of the social and environmental performance of an organisation and to improve relationships with stakeholders. For most of the world’s largest companies, reporting on non-financial information appears to be a continuing trend, so it is essential to present the new corporate reporting trends of the 21st century. The disclosure of socially responsible information will be analysed, with a focus on the application of the Global Reporting Initiative guidelines related to CSR. Global Reporting Initiative (GRI) is the best-known framework for voluntary reporting of environmental and social performance by business worldwide. The main objective of the paper is to explore the corporate voluntary disclosure practices of the listed and non-listed banks in Hungary. The extent of voluntary disclosure has significantly improved for decades worldwide, but the situation is not that obvious regarding the Hungarian financial sector. This paper aims to describe the status of disclosure practices of corporate sustainability in the annual reports, sustainability reports or CSR reports of the banking industry in Hungary. Also, increased corporate visibility and financial risk increase stakeholder demand for transparency on the social impact of financial institutions and their CSR practices. Finally, the analysis and subsequent comparison of available CSR reports of banks will be presented.

  • Temporal Changes of Pyrite Oxidation Rate in Bolivian Sulphidic Mining Wastes
    194-202
    Views:
    181

    Since the 70's, when huge sulphidic open pits were developed, the acidic rock drainage (ARD) become the leader problem of the sulphidic mining industry. Although the recycling is an essential technology, it cannot cover the demand alone, thus mining activity needs to continue. Acidity in mine drainage commonly requires most of the attention, but the main problem is the caused elevated level of metal mobility and leaching, which are generated by the increased rates of sulphide weathering under acidic conditions. The Itos mine is a polymetallic vein deposit in Bolivia, had been mined for silver and tin until 1990, leaving behind much and huge tailings and mine waste heaps, where quite often the pyrite content exceeds 10 %. Serious ARD effects take place in the mine waste heaps. These processes can be well characterized with the pH 1 or 2 of the seepage water, which forms serious alteration in the waste itself and the neighbouring rocks. In three consecutive years, the pyrite oxidation rate was investigated on the same 7 samples by humidity cell test. 5-6 months pauses were left between the humidity cell test periods, which mimics the alternation of wet and dry periods, typical for the place. The results give much more information, than the oxidation rate in the individual test periods, showing the changes by time. This applied method gave good result to characterize the behaviour of the waste in long-term. The column test was complemented with mineralogical analyses, such as electron probe micro analysis. The mineralogical and column test analyses show, that the changes of the pyrite oxidation rate split the samples into three different groups, one where the oxidation rate decreases, second where it increases with time and the third where oxidation rate is maximal and stays stable for several years.

  • Investigation of the Granulometric and Mechanical Properties of Inorganic Used Sand
    302-308
    Views:
    261

    This paper examines the use of a modified inorganic binder in metal-alloy casting. The results of investigations regarding the effect of reusing the used sand multiple times without reclamation. The technological properties of silica sand with inorganic binders were presented, two different temperatures were applied to make the used sands. After lump crushing the inorganic used sand was recycled in order to make a new sand mixture. Our work was focused on the effect of multiple usage of inorganic used sands on the mechanical and granulometric properties prepared with modified inorganic binder.

  • Testing of Micro Switches for Garden Tools
    206-213
    Views:
    173

    The aim of this paper is to introduce the design of testing method for the prediction of the life and acceleration methods of the micro switches applied in different type of garden tools. These products will be tested for complex stressing, for example higher temperature, humidity, current load and so on. Therefore, the most important information and multi-factor acceleration models are summarized, the Weibull, the lognormal and the exponential distributions which are suitable for performing and evaluating tests.

  • Effect of Heat Input on the Toughness Properties of S690QL Steel during Hardfacing
    1-12
    Views:
    21

    In recent years, the use of high-strength steels in hardfacing process has become increasingly common. One typical industrial example is the case of hydraulic shears used in building demolition operations, where the components are exposed not only to significant abrasive wear but also to intense dynamic loading. The use of quenched and tempered high-strength steel grade S690QL has become particularly widespread in this field, primarily as the base material for the hardfacing applied to the most heavily loaded regions of demolition shears. However, quenched and tempered high-strength steels are highly sensitive to the effects of the welding thermal cycle, which typically cause detrimental changes in the microstructure and mechanical properties of the heat-affected zone. The thermal cycles occurring during hardfacing differ from those typical of fusion welding, and consequently, the structure and mechanical properties of the resulting heat-affected zone may also vary. In addition, the penetration depth of the hardface layer can differ, which may significantly alter the load-bearing cross-section of the high-strength steel and, thus, the in-service behavior of the component. In the experimental work, hardfaced samples were performed on S690QL base material using different levels of heat input, thereby producing varying penetration depths. The aim of the study was to determine the effect of penetration depth on the resistance of the hardfaced component to dynamic loading. The tests were carried out at both +20 °C and –40 °C. The results clearly demonstrated that samples with deeper penetration exhibited reduced toughness at both investigated temperatures. 

  • Application of Nanomaterials in Food Industry and Agriculture
    116-126
    Views:
    302

    Nanomaterials have unique application features which can mainly be associated with their size properties. These materials have much higher surface than the normal particle size variant of the same materials. Due to these properties, nanomaterials are widely used in the industry. Food industry and the agrarian sector are using these materials increasingly. The main goal of nano size components and additives are the improvement of some parameters of the food manufacturing process, the elongation of the best before date of the food and the improvement of the texture, stability and the consistence of the food. Probably, nanomaterials will play an important role in the development of the food industry, moreover, it can be anticipated that nanotechnology will also appear there and will influence the whole food chain. It should be noted that food industry is using several nano size class materials which are not referred to as nanomaterials. Some examples are the micelles of some proteins, like milk protein, and fatty acids. Considering all these, the aim of our work was to present a thorough review and summary of the current applications.

  • Application of Rexroth Controlling for Inverted Pendulum
    174-179
    Views:
    259

    This paper deals with the control of an inverted pendulum. Balancing techniques are used in great many controlling problems. The inverted pendulum problem is often used as a benchmark. The theoretical background is well-known and easy to treat. A commercially available Rexroth axis controller and a CKK compact module are used to control the input of the system, which is usually applied in industrial fields. A test bench has been designed and built. A PLC based program has been developed to swing up the pendulum from the rest location to inverted position and LQR controller is designed to balance the system.

  • Safe, Health Working in Health Care in the Shadow of a Pandemic
    85-97
    Views:
    323

    Safe work that does not endanger health is a complex category, the provision of which creates an obligation on the part of the state, the employer and the employee. The task of the state is to determine the basic requirements for work that does not endanger health and safe, as well as the related rights and obligations, and to develop a national policy on occupational safety and health. As a result of the coronavirus epidemic in early 2020, we have faced a whole new form of accidents at work and occupational diseases. In my study, I want to examine the course of the investigation of the infection that takes place during the pandemic in healthcare work, and the possibilities of remuneration for the duration of the illness.

  • Design of Chip Conveyor
    81-85
    Views:
    204

    The following article examines the design methodology of screw conveyors. The most significant steps are discussed concerning the design of the apparatus and its use in machine tools as a service component is explained.

  • The Impact of Optical Character Recognition Artificial Intelligence on the Labour Market
    9-16
    Views:
    512

    Because of present day information technology, there is neither need to plant complicated computers for more millions price if we would like to process and store big amounts of data, nor modelling them. The microprocessors and CPUs produced nowadays by that kind of technology and calculating capacity could not have been imagined 10 years before. We can store, process and display more and more data. In addition to this level of data processing capacity, programs and applications using machine learning are also gaining ground. During machine learning, biologically inspired simulations are performed by using artificial neural networks to able to solve any kind of problems that can be solved by computers. The development of information technology is causing rapid and radical changes in technology, which require not only the digital adaptation of users, but also the adaptation of certain employment policy and labour market solutions. Artificial intelligence can fundamentally question individual labour law relations: in addition to reducing the living workforce, it forces new employee competencies. This is also indicated by the Supiot report published in 1998, the basic assumption of which was that the social and economic regulatory model on which labour law is based is in crisis.

  • Numerical analysis of effects of an open-pit coal mine to groundwater
    70-74
    Views:
    256

    In this study we investigated the hydrogeological problems of an open-pit brown coal mine in the Borsod coal basin with Processing Modflow software. The coal mine is located in the valley of the Sajó-river with high transmissivity overburden layer where the traditional dewatering solutions were not encouraging due to inrush risks and low cost-efficiency. A new way of barrier forming was found out and numerically simulated to prove the efficiency of the solution. Since there are several contaminated sites in the surroundings it was a key factor to assure that the new mine dewatering technique has only a negligible effect on the groundwater regime that undisturbs the known contaminant plumes nearby.

  • Determination of the Differential Equations of a Dynamical System using Dual Description
    41-48
    Views:
    159

    The paper deals with the description of a mathematical model of a mechanical system using the so-called energy-based approach. The model is created using both generalized displacements and generalized momenta. The latter prescription method is less common in practice, due to its complexity. The two ways are presented through the same example mechanical problem, and a control task is also solved with the help of a PID block.

  • Innovative Utilization Possibilities of Industrial Wastes from Hungary as Construction Industrial Material
    203-212
    Views:
    204

    The research results carried out at the University of Miskolc Faculty of Earth Science and Engineering in the Center of Excellence of Sustainable Natural Resource Management show that the physical and mechanical properties of the construction industrial products (strength, compactness) made of waste sources can be controlled reasonably by the appropriate processing technologies and under optimized circumstances and characteristics (particle size distribution, specific surface area). It was established that beside the chemical activation, the mechanical activation of solids is an effective tool for improving the product characteristics. However, this modifies the physical as well as structural, mineralogical properties of the raw materials, therefore its determination is of great importance.

  • Boundary Value Problem for a Heated Nanofluid Flow in the Presence of Magnetic Field
    58-66
    Views:
    172

    The aim of this paper is to introduce some new numerical results on the magneto-thermomechanical interaction between heated viscous incompressible magnetic nanofluid and a cold wall in the presence of a spatially varying magnetic field. The governing nonlinear boundary layer equations are converted into coupled nonlinear ordinary differential equations by similarity transformation. The ODE system is solvable numerically for example using higher derivative method. The investigation is focused on the influence of governing parameters corresponding to various physical conditions. Numerical results are exhibited for the dimensionless wall skin friction and for heat transfer coefficients at the wall, along to distributions of the velocity and the temperature.

  • Environmental Index and Environmental City Resilience Index calculation for Four Settlements in Szabolcs-Szatmár-Bereg County and Four in Győr-Moson-Sopron County
    17-29
    Views:
    252

    Globalization and urbanization pose a number of challenges for different settlements. Stakeholders seek to cure global problems through sustainable projects. Since the Brundtland Commission's definition of sustainable development in 1987, the approach to sustainability has permeated all dimensions of the economy, including the environmental dimension. In Hungary, IBM conducted a study (Lados - Horváthné Barsi, 2011), in which the search for green, sustainable solutions defined in the definition of a livable city plays a key role. The characteristics of sustainable cities, that they are resilient to disasters, return to equilibrium after a shock has occurred (Seeliger, Turok, 2013). Resilience can also be mentioned as one of the pillars of sustainability. In a UN-Habitat statement, resilience refers to the ability of any urban system to withstand and recover from multiple shocks and to maintain the continuity of its services (OECD, 2018). In my study, I would like to present the results of the environmental index and the Environmental Urban Resilience Index (EURI) of the four largest cities selected on the basis of the population in the easternmost and westernmost counties of the country.