Title of the article | MECHANICAL AND MATHEMATICAL MODELS OF ONE TYPE OF BLOCK ELEMENTS FOR PROBLEMS OF UNDERGROUND GEOMECHANICS |
Authors |
ZHURAVKOV Michael A., D. Sc. in Phys. and Math., Prof., Head of the Department “Theoretical and Applied Mechanics”, Belarusian State University, Minsk, Republic of Belarus, Belarusian State University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. NIKOLAITCHIK Mikhail A., M. Sc. in Phys. and Math., Head of the Research Laboratory “Applied Mechanics”, Belarusian State University, Minsk, Republic of Belarus, Belarusian State University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. Shiqi ZHANG, Master’s Student of the Mechanics and Mathematics Faculty, Belarusian State University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. |
In the section | GEOMECHANICS |
Year | 2023 |
Issue | 3(64) |
Pages | 73–82 |
Type of article | RAR |
Index UDK | 539.3;539.422.23;622.83 |
DOI | https://doi.org/10.46864/1995-0470-2023-3-64-73-82 |
Abstract | The article presents a procedure for constructing mechanical and mathematical models to describe the stress-strain state of one type of block element, taking into account its own deformation. On the basis of this type of block element, it seems promising to build an implementation of the discrete element method for modeling the mechanical state of rock masses in areas of a clear violation of the continuity hypothesis. The introduced block element can be used both for issues under static loading and in the case of dynamic problems. |
Keywords | numerical methods, mechanics of deformable solids, discrete element method, underground geomechanics, deformable block element, continuous-discrete models |
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Title of the article | OPTIMIZATION OF CONCENTRATION OF ANTIOXIDANT ADDITIVE IN PLASTIC LUBRICANT BASED ON RAPESEED OIL |
Authors |
GRIGORIEV Feodor A., Junior Researcher of the Department “Friction, Lubrication and Operating Resistance of Materials”, V.A. Belyi Metal-Polymer Research Institute of National Academy of Sciences of Belarus, Gomel, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. PODGORNAYA Viktoriya V., Ph. D. in Phys. and Math., Assoc. Prof., Deputy Director for Science, V.A. Belyi Metal-Polymer Research Institute of National Academy of Sciences of Belarus, Gomel, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. MARCHANKA Larysa N., Ph. D. in Eng., Assoc. Prof., Head of Fundamental and Applied Mathematics Department, Francisk Skorina Gomel State University, Gomel, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. KAVALIOVA Inna N., Ph. D. in Eng, Assoc. Prof., Leading Researcher of the Department “Friction, Lubrication and Operating Resistance of Materials”, V.A. Belyi Metal-Polymer Research Institute of National Academy of Sciences of Belarus, Gomel, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. |
In the section | MATERIALS SCIENCE IN MECHANICAL ENGINEERING |
Year | 2023 |
Issue | 3(64) |
Pages | 66–72 |
Type of article | RAR |
Index UDK | 539.621 |
DOI | https://doi.org/10.46864/1995-0470-2023-3-64-66-72 |
Abstract | Plastic lubricant with rapeseed oil dispersion medium is considered with addition of diphenylamine antioxidant additive. Analysis of tribotechnical, chemical and physicо-mechanical characteristics of the obtained lubricants with content of antioxidant additive from 0.5 to 10.0 wt.% is carried out. The effect of the additive concentration and temperature of introduction on the functional characteristics of lubricants is shown. A comprehensive method is proposed for evaluating the optimal concentration and temperature of the antioxidant additive introduction using an integral indicator, according to the lubricant total functional characteristics. It is noted that for plastic lubricant with a rapeseed oil dispersion medium and a dispersion phase based on a complex calcium thickener, the optimal temperature range for introducing an antioxidant additive is 85–95 °C at the cooling stage, at a concentration of 1.0 wt.%. In this case, the best combination of the finished product functional characteristics is achieved. Based on the proposed methodology and taking into account the experimental data, using expert criteria it is possible to optimize the concentration and temperature of introduction of antioxidant additive diphenylamine, to obtain a plastic lubricant with given characteristics. |
Keywords | plastic lubricant, calcium complex thickener, rapeseed oil, friction, tribofilm, oxidation, integral indicator, modeling, environmental safety |
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Title of the article | STRUCTURAL MECHANISM OF PERFORMANCE LOSS OF COPPER COOLERS OF GLASS PRODUCTION WITH THERMAL DIFFUSION PROTECTIVE LAYER |
Authors |
KONSTANTINOV Valery M., D. Sc. in Eng., Prof., Head of the Department “Materials Science in Mechanical Engineering”, Belarusian National Technical University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. PLETENEV Ilya V., Ph. D. Student of the Department “Materials Science in Mechanical Engineering”, Belarusian National Technical University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. DASHKEVICH Vladimir G., Ph. D. in Eng., Assoc. Prof., Associate Professor of the Department “Materials Science in Mechanical Engineering”, Belarusian National Technical University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. SUDNIKOV Mitrofan A., Ph. D. Student of the Department “Materials Science in Mechanical Engineering”, Belarusian National Technical University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. |
In the section | MECHANICAL ENGINEERING MATERIALS AND TECHNOLOGIES |
Year | 2023 |
Issue | 3(64) |
Pages | 51–59 |
Type of article | RAR |
Index UDK | 666.1.002.5 |
DOI | https://doi.org/10.46864/1995-0470-2023-3-64-51-59 |
Abstract | A general assessment of options for increasing the resistance of elements of heat-removing devices made of copper is carried out. The peculiarity of high-temperature corrosion destruction of thermal diffusion aluminum- containing protective layer on M1 grade copper as the most common cause of loss of efficiency is studied. The proposed mechanism for the destruction of the thermal diffusion protective layer on the lamellar element of a cooler of glass production is shown, which is caused by two competing processes — layer “resorption” and structural changes during phase interaction. The mechanical destruction features of the protective layer are studied during pure bending and the formation of penetrating cracks deep into the product. The elastoplastic properties of the main structural components of the diffusion layer are studied by the nanoindentation method, and the values of their plasticity index are established. |
Keywords | thermal diffusion layers, brittleness, intermetallic compounds, copper aluminides, heat resistance of copper |
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Title of the article | THERMODYNAMIC ANALYSIS OF THE FORMATION OF A NANOSTRUCTURAL POLYCRYSTALLINE MATERIAL BASED ON NANODIAMONDS MODIFIED WITH NON-DIAMOND CARBON (PART 1) |
Authors |
SENYUT Vladimir T., Ph. D. in Eng., Assoc. Prof., Leading Researcher of the Laboratory of Nanostructured and Superhard Materials, Joint Institute of Mechanical Engineering of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. VITYAZ Petr A., Academician of the NAS of Belarus, D. Sc. in Eng., Prof., Chief Researcher of the Department of Technologies of Mechanical Engineering and Metallurgy, Joint Institute of Mechanical Engineering of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. PARNITSKY Alexander M., Ph. D. in Eng., Senior Researcher of the Laboratory of Nanostructured and Superhard Materials, Joint Institute of Mechanical Engineering of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. |
In the section | MATERIALS SCIENCE IN MECHANICAL ENGINEERING |
Year | 2023 |
Issue | 3(64) |
Pages | 60–65 |
Type of article | RAR |
Index UDK | 621.762:621.921.34 |
DOI | https://doi.org/10.46864/1995-0470-2023-3-64-60-65 |
Abstract | The influence of the size of carbon particles on the parameters of the graphite–diamond phase transformation is considered. It is shown that the surface energy of carbon nanoparticles of various shapes (spherical, columnar) makes a significant contribution to their total thermodynamic potential, which leads to a shift in the diamond–graphite equilibrium curve to the low pressure region and an expansion of the diamond phase stability region. At the same time, the change in the chemical potential (Gibbs free energy) during the direct (not catalytic) transition of thin-film graphite-like nanostructures into diamond will be higher than for “massive” graphite, which leads to an increase in the pressure of phase transformation into diamond. To reduce the parameters of diamond formation and obtain nanostructured diamond polycrystals, it is proposed to use nanodiamond particles with a nanometer surface layer of non-diamond (graphitelike) carbon as the starting material. In this case, the nanodiamond surface will influence the transition of a nanometer layer of graphite (graphite-like carbon) into diamond under more favorable thermodynamic parameters. |
Keywords | nanodiamond, non-diamond forms of carbon, state diagram, phase transformations, chemical potential, Gibbs energy |
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Title of the article | LOADS OF THE TELESCOPIC BOOM FROM LOCAL LOADS DURING TELESCOPING |
Authors |
POTAKHOV Egor A., Ph. D. in Eng., Engineer of the Technical Department of the Rolling Stock Service of the Metro Administration, St. Petersburg Metro SUE, Saint Petersburg, Russian Federation, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. |
In the section | DYNAMICS, DURABILITY OF VEHICLES AND STRUCTURES |
Year | 2023 |
Issue | 3(64) |
Pages | 43–50 |
Type of article | RAR |
Index UDK | 621.873.2/.3 |
DOI | https://doi.org/10.46864/1995-0470-2023-3-64-43-50 |
Abstract | One of the main factors affecting the performance of telescopic booms is the loss of local stability of the shelves and section walls. The loss of local stability of the sections occurs due to the development of plastic deformations in some of the most loaded sections of the telescopic booms or as a result of the loss of stable equilibrium of the sections even at the stage of elastic deformation. In this case, the maximum stresses of the telescopic boom are formed in the sections of the location of the supporting elements, where the summation of deformations from external loads and forces acting from the side of the supporting elements (local loads) occurs. The aim of the work is to study the loading of telescopic boom from the action of local forces in the process of telescoping. Analysis of the loading of telescopic boom in the process of extending (retracting) the sections is carried out using the example of the boom equipment of a railway crane Sokol 80.01M. Numerical modeling is used to study the local loading of telescopic boom of a crane during telescoping. Three telescoping modes are selected: consecutive extension (retraction) of sections without load; synchronous extension (retraction) of sections without load; consecutive extension (retraction) of sections with a load. The results of the virtual experiment for each mode are the time dependences of the local forces generated at the locations of the sliding bearings, and the time dependences of the vertical loads on the pins of the telescoping hydraulic cylinders. A comparison was made of the greatest loadings of the boom and telescoping hydraulic cylinders formed with three options for extending (retracting) sections. Based on the obtained dependencies of local loads, the maximum stresses of the telescopic boom were calculated during each telescoping mode. |
Keywords | telescopic boom, local loads, telescoping, crane |
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