bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mathematical model of wedge-shaped plain bearing considering the dependence of viscosity on pressure
Authors: Mukutadze A , Prikhodko V , Dolgiy I 
Published: December 2021

Abstract
This paper outlines a new approach for finding an asymptotic and exact self-similar solution for the zero and first (without taking into account the melt and considering the melt, respectively) approximation of the wedge-shaped plain bearing with a non-standard support profile of the slide and the low-melting metal coating of the surface. The given approach is based on the flow equation of a ferromagnetic fluid for a «thin layer», the continuity equation, as well as the equation describing the profile of the guide’s molten contour. The proposed method takes into account the dependence of the rheological properties of the lubricant and the melt that have ferromagnetic properties in the laminar flow on pressure. We have succeeded in obtaining accurate analytical dependences for the field of velocities and pressure at zero and first approximations and the ones for the profile of the guide’s molten surface. Besides, we have managed to determine the key performance properties for the slide–guide friction pair, including load-bearing capacity and friction force. Finally, we could assess how the bearing capacity and friction force are influenced by parameters caused by the coating melt adapted to the conditions of the support profile friction and a parameter that characterize the rheological properties of the lubricant.
The performance evaluation of heavy loaded tribosystems with vacuum ion-plasma PVD and DLC coatings
Authors: Kolesnikov V , Manturov D , Kolesnikov I 
Published: December 2021

Abstract
The results of studies of the physical, mechanical and tribological characteristics of PVD and DLC coatings are presented. The complex of basic mechanical properties (hardness H and elastic modulus E), as well as derivatives of mechanical characteristics H/E and Н3/Е2
, were investigated by the method of continuous indentation at various loads. The friction coefficient, the wear rate of the sample and the counterbody were determined as tribological indicators. The applied purpose of the work was to determine the friction unit for applying the developed coatings, materials and modes of applying PVD and DLC coatings. To solve this problem, a test bench was designed and built that simulates the operation of the selected friction unit. As a result of the research carried out, the results of laboratory and bench tests were compared. The performance of the coatings was determined by the volume of the tooth wear of the sleeve and the tip with the help of the method of micrometric measurements. As a result of the study of the surface morphology, the volumes of wear of rubbing conjugations and the intensity of their wear were determined. It has been established that the results of bench tests confirm laboratory studies and suggest that such an installation can be used for researching other heavily loaded spline conjugations.
The prospects and scientific solutions for the application of the innovative technologies to create vacuum-levitation vehicles
Authors: Kolesnikov I , Kolesnikov V , Boiko M 
Published: December 2021

Abstract
The elevated transport system is currently being challenged to increase speed. Of course, Russia is facing this problem because of its vast territory connecting the economic centers of the European Union - the North American continent - Southeast Asia. The answer to this challenge is the vacuum-levitation transport system (hereinafter VLTS), which significantly increases the speed of freight and passenger traffic. In fact, you can list many more tasks when creating VLTS - these are issues of safety, earthquakes, landslides, floods, karsts and others, but we will focus on the field of chemistry and the sciences of composites, which will be the subject of this article. When developing VLTS, it is necessary to determine the behavior and reliability of friction units - this is a braking system, a center plate - a thrust bearing, a reducer, etc. The fundamental difference between tribocontact surface layers operating in air and vacuum is that oxide films are formed during friction in a gas environment and thus there is no contact between juvenile surfaces, and in a vacuum, juvenile surfaces are seized, which leads to intense wear. The article presents a technology for increasing the wear resistance of metal-polymer friction units, taking into account the properties of polymer composites to form secondary structures on the friction surface.
Reactive inductor machines on transport
Authors: Grebennikov N , Kireev A 
Published: December 2021

Abstract
The experience of using reactive inductor machines (RIM) on vehicles is described. Over the past decade, the interest in RIM for the transport industry has significantly increased. One of the promising areas of RIM use is hybrid vehicles. A RIM has a simple design, high reliability and performance. It is capable of operating in motor and generator modes. The world experience in the development of vehicles with RIM has been promising in using this type of electric machines in electric power transmissions of locomotives.
Thermal processes in the stack of perishable cargo transported in the heated isothermal car
Authors: Voron O , Moiseev V 
Published: December 2021

Abstract
The article deals with the organization of heat exchange processes when using a new heating system for the cargo room of the isothermal car. Using the example of considering a stack formed from glass containers with fruit juices packed in cardboard boxes, the equivalent thermophysical characteristics of the cargo in the stack are formulated. Analytical methods are used to determine the main regularities of the regular thermal regime and the nature of thermo-gravitational flows in the cargo room of the car. The possibilities of improving the design of the heating system of the cargo room of isothermal rolling stock for the transportation of perishable cargo are considered. The possibilities of modernization of specialized equipment allowing optimization of the temperature regime in the cargo room of the car are presented. The article deals with the organization of heat exchange processes when using a new heating system for the cargo room of the isothermal car. Using the example of considering a stack formed from glass containers with fruit juices packed in cardboard boxes, the equivalent thermophysical characteristics of the cargo in the stack are formulated. Analytical methods are used to determine the main regularities of the regular thermal regime and the nature of thermo-gravitational flows in the cargo room of the car. The possibilities of improving the design of the heating system of the cargo room of isothermal rolling stock for the transportation of perishable cargo are considered. The possibilities of modernization of specialized equipment allowing optimization of the temperature regime in the cargo room of the car are presented.
Error analysis of the cutting machine step adjustable drive
Authors: Rudikov D A , Ilinykh A S 
Published: December 2021

Abstract
The implementation precision of a number of adjustment bodies of a metal-cutting machine is also the most important indicator of its quality, a strictly standardized industry standard, technical conditions for manufacturing and acceptance. Moreover, the standard for limiting the error is set depending on the used denominator of the series. An essential feature of the precision of the series being implemented is that it is determined not by an error in parts’ manufacturing, but by the disadvantages of the used method of kinematic calculation. The established modes largely determine the efficiency of processing on metal-cutting machines. If the setting is set to an underestimated mode, then the performance is reduced accordingly. In the case of the mode overestimation, this leads to a decrease in durability and losses due to increased regrinding and tool changes. Creation of a complex of mathematical models for the design kinematic calculation of the metal-cutting machines’ main movement drive, which allows reducing the error in the implementation of a series of preferred numbers and increasing machining precision. The article provides a mathematical complex for analyzing the total error components, which allows determining and evaluating the total error of the drive of a metal-cutting machine by analyzing its constituent values with high precision: errors of a permanent part, errors of a multiplier part, rounding errors of standard numbers, errors in the electric motor and belt transmission. The presented complex helps to identify the role of the rounding error of preferred numbers in the total relative error formation and makes it possible to reduce it, which allows solving the problem of increasing the step adjustable drive precision. When using a mathematical complex, a fundamentally new opportunity for creating a scientific base appears, developing algorithms and programs for engineering calculation of tables that facilitate the selection of the numbers of teeth for multiple groups, structures and guaranteeing high precision of the implemented series.
Study of heat transfer during steam condensation in the tubes of diesel radiator cores
Authors: Sklifus Ya K , Ignatieva O V 
Published: December 2021

Abstract
The article contains an assumption about the practicability of using the processes of boiling and condensation of the coolant in the cooling system of a locomotive diesel in order to reduce the energy consumption of fans of the refrigerating chamber. The possibility of using of standard radiator cores of a diesel locomotive with flat tubes as steam condensers is considered. The results of the criterion equation of heat transfer from steam to a flat tube during condensation, obtained by the mathematical model of this process, are estimated. The assessment was carried out by comparison with experimental data. The influence of the initial steam velocity, the corresponding tube diameter, the working length of the tube, the physical properties of steam and condensate is considered. The comparison of the influence of these factors on heat transfer in round and flat tubes of a locomotive radiator core is carried out. The processed results of physical and numerical experiments for both circular and flat tubes are shown in the graphs and regression equations. The advantage of flat tubes over round ones in terms of heat transfer intensity during steam condensation, which can reach 24%, for a standard radiator core of a diesel locomotive was found.
Justification of the structure and determination of the mathematical model parameters for a mechanical system with tribospectral optimization
Authors: Shcherbak P , Kuznetsova M , Razuvaev D 
Published: December 2021

Abstract
The questions of determining the structure and parameters of the working bodies mechanical system model for the track renewal train with tribospectral optimization are considered. It is proposed that the tribospectral characteristics should be considered as an optimization parameter recognition source. The main attention is paid to the identification of the main regularities in the realized tribospectrum of the useful vibration signal. Based on the results of processing the vibration acceleration spectra, possible signs of optimization assessment are proposed.
Luminescence decay kinetics as a tool for quality control of polymer materials used in railway transport
Authors: Nikitchenko V , Gromova E , Semenov A , Ruban A 
Published: December 2021

Abstract
Protective coatings and composite materials based on polymer materials are widely used. They are used in construction, railway, water and air transport to protect various structures from the harmful effects of the environment. In order to create new materials with greater strength and durability, the research related to the development of methods for controlling their quality and the formation processisneeded.The luminescence of chromophores (molecules capable of luminescence) attached to polymer molecules (polymer chains) is an effective tool for this control. The paper discusses the effect of the polymer chain size and the nature of the interaction of its units on the chromophores’ luminescence decay kinetics.
Detection of particles of dark matter from the spectrum of secondary particles in high-energy proton-proton collisions in a thermodynamic model
Authors: D’yachenko A T , Gromova E S 
Published: December 2021

Abstract
In a simple hydrodynamic model, the transverse momentum distributions are found for A hyperons formed in pp collisions at ultrarelativistic energies. The calculated spectra are compared with the experimental data obtained for various colliders in a wide range of proton collision energies, including the data from experiments at the Large Hadron Collider. An interpretation of the transverse momentum spectra of soft photons in pp collisions is proposed, taking into account the X17 boson with a mass of 17 MeV - a new particle, a possible candidate for the role of dark matter particles. A tube model is proposed on the basis of combining two-dimensional quantum chromodynamics and quantum electrodynamics. An interpretation is proposed for the detection of a 38 MeV boson in the spectra of photons emitted in the reactions of protons with carbon nuclei at an incident proton momentum of 5.5 GeV/c. The X38 boson with a mass of 38 MeV has a mass close to the boson mass obtained by us, equal to 35 MeV for an electromagnetic tube. This new particle was discovered in experiments carried out recently in Dubna for the reactionp p + C→2γ + X. To interpret the obtained experimental data on the spectra of emitted photons depending on their mass, it is proposed to use the formulas obtained for massive particles, setting the mass of a boson decaying into two photons equal to 38 MeV. It was proposed to consider bosons X17 and X38 as particles of dark matter.
Control of plasma spatial distribution in gas discharge lamps filled with alkali metal vapors
Authors: Lapshin V F , Yu Florinsky V 
Published: December 2021

Abstract
The thermodynamic properties of alkali metal vapor plasma in the pressure range 0.25 - 3.0 atm and temperatures 1500 - 60000 K are considered. It is shown that a distinctive feature of this plasma is the existence of a relatively narrow critical temperature interval in which the plasma consists only of electrons and singly ionized atoms. The specific heat capacity of the plasma has a minimum value in the critical temperature range, corresponding to the heat capacity of a simple e-i plasma in which the second ionization of atoms has not begun. It has been shown that, due to this property, in gas discharge lamps filled with alkali metal vapors, it is possible to control the type of spatial distribution of the plasma. Under relatively low currents, when the temperature of the plasma doesn’t reach the critical range of the value, the traditional space distribution of the plasma is realized in the gas discharge tube. In this case, most of the plasma is concentrated in the axial region of the tube and its concentration decreases along the radius from the axis to the walls of the tube. With sufficiently high currents, when the plasma temperature on the axis exceeds the values from the critical interval, the opposite case is realized: the main part of the plasma is now concentrated on the periphery of the gas discharge volume. In this case, the plasma concentration increases along the radius from the axis to the tube walls. It is shown that the transformation of one type of spatial distribution of plasma into another occurs when the plasma temperature on the axis reaches values from the critical interval and the specific heat capacity approaches its minimum value, corresponding to a simple plasma consisting of electrons and single-charge ions.
Mathematical modeling of a new method of transportation of viscous petroleum products at low air temperatures
Authors: Moiseev V I , Ksenofontova V A 
Published: December 2021

Abstract
High viscosity petroleum products such as fuel oils and cracking residues are widely used as marine and boiler fuels both in Russia and in its exports. Conveying viscous petroleum products at low air temperatures has a high cost due to the unloading and cleaning processes of the transport tanks. Refined petroleum product cools and solidifies during transportation, becoming highly viscous, making it impossible to drain it without preheating to restore fluidity. Emerging difficulties are common to all countries with long winters and geographically wide areas. To justify a new method of rail transport of viscous petroleum products while maintaining their high temperature and fluidity by suppressing the natural convection of the petroleum product at the stage of filling the tanker. Temperature field calculations using the finite element method and the ANSYS R18.2 package are presented. The business process of the proposed transport method is universal for all modes of transportation. Using Petri nets and simulation modelling, it is investigated using the example of cleaning a tank car boiler from highly viscous residual oil products. You must perform these operations periodically during the operation of the tank wagon, and they are mandatory before every scheduled inspection and repair. Viscous oil products can be transported in a new way, the duration of the cleaning process of the tank wagon boiler is reduced by three times and the amount of water consumed is reduced by one and a half times.
Assessment of the switching time and fluid type influence on the transient quality in hydro-mechanical systems
Authors: Osipov A V , Kurilkin D N 
Published: December 2021

Abstract
The number of transients in hydro-mechanical power transmissions accounts for a significant portion of the total operating time and has a significant impact on drive economy. The quality of the transients largely depends on their duration and the type of working fluid used. The purpose of the work is to analyze the transients in the hydro-mechanical system, taking into account the effect of the duration of switching processes and the type of working fluid used. Determination of transient parameters in the hydro-mechanical power transmission was performed on the basis of mathematical dependences describing the switching process of two torque converters depending on the duration of the filling and emptying process and the influence of the type of working fluid used. Analysis of the calculated characteristics of transients in hydromechanical power transmissions showed that the main factor in the switching of torque converters, is the combination of filling and emptying processes, depending on the type of working fluid used. The obtained results give grounds to propose recommendations on coordination of filling and emptying processes in order to increase the efficiency of the hydromechanical drive.
Physical processes simulation in a precision device for liquid samples thermal cycling
Authors: Kiselev I G , Belov D A 
Published: December 2021

Abstract
An urgent task is the development of devices that provide a precision temperature change. The devices used in the real-time polymerase chain reaction method require not only repeated cyclic temperature changes with high accuracy, but also the temperature gradient minimization over the working fluid. In this article, the modeling of the working processes taking place in the thermal block of the device with the previously proposed thermohydraulic system, which ensures the temperature change together with the Peltier elements, is carried out. A mathematical model is formulated and a differential equation, boundary and initial conditions are substantiated. Numerical methods for solving the mathematical model in the Elcut software were applied. An experimental setup was developed and a study of heat exchange processes in the thermal block of a nucleic acid analyzer with a thermohydraulic system was carried out, confirming the adequacy of the developed mathematical model.
Operation of vibration source of an unbalance type with liquid-filled internal working chamber
Authors: Savchenko A , Nikolaev A , Evstigneev D 
Published: December 2021

Abstract
Equipment for increasing water inflow to the well is proposed, which affects the aquifer by seismic vibrations. The method is based on accelerating the filtration process in soils, exposed to vibration. The equipment can work in conjunction with a submersible pump and has the ability to pump liquid through the working chamber of the generator. Generators can be combined into a group and driven by one electric motor to increase the efficiency of vibration treatment. This method is built into the existing technology of dewatering and pits drainage. The dynamics of the vibration source operation of an unbalance type with a liquid-filled inner chamber was studied in laboratory conditions, on a test. The vibration source was attached to the stand frame and was in a vertical position coaxially with the electric drive, thereby simulating its location in the well. The unbalance was unwound by an electric drive with a rotation frequency of 10 to 50 Hz in 5 Hz steps and seismic vibrations, generated by a vibration source, were recorded. Based on the experiments’ results, the amplitude-frequency characteristics of an unbalanced vibration source in the low-frequency range with a dry and liquid-filled inner chamber were obtained. In order to prevent the bearing assemblies from jamming, their heating was monitored with a thermal imager and temperature sensors.
Longitudinal-transverse thermal- force bending and stability layered inhomogeneous profiled rod
Authors: Mishchenko A 
Published: December 2021

Abstract
The solution to the problem of the stress-strain state of an inhomogeneous profiled rod is based on the use of nonlinear equilibrium conditions and physical relations of a layered thermo elastic thin rod. A differential equation of bifurcation inhomogeneous rod stability of variable cross-section is obtained. The equation has variable functional coefficients. In the initial state, the rod is subjected to bending with the implementation of one of the asymmetric shapes. The critical state occurs under the action of a longitudinal load corresponding to one of the lowest symmetrical shapes, orthogonal to the initial shape. In the first series, numerical calculations of an inhomogeneous I-rod with a variable cross section height are performed. Shelves and wall I-rod are made of steel, aluminum and titanium alloys. The graphs of maximum deflection and normal stresses acting at the calculate points at the boundaries of the layers are plotted depending on the longitudinal load at the given levels of transverse loads and thermal field. A significant influence of the rod physical structure, the profiling its form and the factor of nonlinearity of static relations on the stress fields has been established. A homogeneous temperature field with a nominal value of 80°C creates fields of self-balanced stresses in an inhomogeneous rod. The components of normal stresses in this case reach 20-40% of the materials permissible resistance level. The presence of rod parts with a significant difference in the coefficients of thermal expansion in the composition enhances this effect. In the second, the stability analysis of an inhomogeneous I-rod with a variable width cross section was performed. The transition of the initial S-shaped bend to an unstable state is shown.