bluuebunny/crossref_metadata_2025_split huggingface dataset:
The dynamics of explosive vaporization of a two-component liquid mixture
Authors: Kozulin I A , Kuznetsov V V 
Published: November 2019

Abstract
The dynamics of explosive vaporization of the 2-propanol/water and ethanol/ water mixtures on the multilayer thin-film resistor with the size of 100×110 m has been investigated. An original optical method based on measuring the laser intensity reflected from resistor surface was used. The characteristics of the initial stage of the explosive vaporization of two-component mixtures were obtained. The dependence of the temperature of explosive vaporization on the rate of temperature growth and the dependence of the boiling time on effective heat flux were defined.
Multispark initiation of ring gas charges in water
Authors: Teslenko V S , Drozhzhin A P , Medvedev R N 
Published: November 2019

Abstract
The experimental results of studying in-water initiation of propane-oxygen charges in the form of ring bubbles by using 2, 4 and 6 electrical sparks have been presented. In discharge gaps, sparks were initiated from the single capacitor storage of energy 2 J and were located along the ring perimeter of diameter 52 mm at the same distance from each other. The difference between the processes of energy release in the combustion of gas charges has been revealed in the analysis of force pulses measured by the piezo-dynamometer with time resolution of 2.6 µs. It has been shown that for the same gas charges in the initiation of gas by multispark discharges, thrust characteristics have both qualitative and quantitative advantages. As the number of sparks increases from 2 to 6, the amplitude of force pulses rises to 30% and a specific pulse increases to 20% for the same gas charges.
Evolution of liquid-drop aerosol cloud during deposition in a high-temperature environment
Authors: Arkhipov V A , Zharova I K , Kozlov E A , Maslov E A , Perfilieva K G , Tkachenko A S , Bulavko A M 
Published: November 2019

Abstract
Physical-mathematical model of the evolution of a liquid-drop aerosol cloud in the atmosphere during fire extinguishing with the help of aviation is presented. Some results of calculations of the motion, heating and evaporation of polydisperse water droplets during refrigerant medium discharge from the aircraft board are given.
Analysis of hydrophysical fields in the northern part of the Black Sea on the basis of assimilation in the hydrodynamic model of temperature and salinity observations in the summer season of 2016
Authors: Demyshev S , Evstigneeva N , Dymova O 
Published: November 2019

Abstract
A numerical experiment was conducted to reconstruct the fields of the currents, the level, temperature and salinity of the Black Sea for the summer season of 2016 on the basis of the hydrodynamic model that included nonlinear equations of motion, advection equations of heat and salt. We used a high spatial resolution (horizontal grid ∼1.6 ×1.6 km and 27 vertical layers) and real atmospheric forcing. The assimilation procedure of observational data was based on a modified Kalman filter taking into account the heterogeneity and non-isotropy of estimates of the temperature and salinity fields. Areas of generation of meso- and submesoscale features of hydrophysical fields were determined in the northern part of the Black Sea (eddies of different signs of rotation with a radius of about 30 km in the western part of the region, a cyclonic eddy with a radius of about 40 km in the eastern deep-water part of the region, anticyclonic eddy with a radius of about 25 km near the city of Yalta, intense jets along the Crimean coast and eddies of small scales of a different sign of rotation along the coast of Crimea and on the north-western shelf) and possible reasons of their formation were discussed.
Numerical simulation of the laminar-turbulent transition on a swept wing in a subsonic flow
Authors: Kirilovskiy S V , Boiko A V , Demyanko K V , Ivanov A V , Nechepurenko Y M , Poplavskaya T V 
Published: November 2019

Abstract
A subsonic (U∞=30 m/s) flow around a swept wing with a sweep angle of 45° and a chord of 700 mm aligned at an angle of attack in the test section of the T-324 wind tunnel based at the Khristianovich Institute of Theoretical and Applied Mechanics of the Siberian Branch of the Russian Academy of Sciences is considered. The experiments include measuring the static pressure on the model surface and thermal imaging of the laminar-turbulent transition (LTT). The numerical simulations of the laminar flow are performed by means of solving three-dimensional Navier-Stokes equations with the use of the ANSYS Fluent CFD software. The LTT position is determined by an LTT module developed by the authors on the basis of a LOTRAN 3.0 software package. The predicted results agree well with the experimental data and confirm that the favorable pressure gradient in the flow around the wing aligned at an angle of attack of −5° prevents the growth of the Tollmien-Schlichting waves and the LTT on the major part of the upper surface of the wing due to instability of crossflow vortices.
Reconstruction of the mesoscale variability of the Black Sea based on assimilation in the model of three-dimensional fields of pseudo-measurements of temperature and salinity
Authors: Lishaev P N , Kubryakov A A 
Published: November 2019

Abstract
The paper presents the results of the analysis of the hydrophysical fields of the Black Sea, reconstructed in the reanalysis through the assimilation in the model of pseudo-measurements of temperature and salinity. Much attention was paid to assessing the reproduction of mesoscale eddies. To perform a retrospective analysis of hydrophysical fields, three-dimensional temperature and salinity fields obtained by the original method of joint analysis of data on sea-level anomalies and rare contact measurements were acquired in the model. To identify the eddy structures, an automatic identification procedure is used, based on the definition of closed streamlines in the velocity fields. The coordinates of the eddy, trajectories of motion, velocity, time of life and vertical structure are calculated.
Simulation of the liquid fuel spraying based on Eulerian-Lagrangian model
Authors: Kuznetsov V , Shebelev A , Sharypov O , Dekterev A , Minakov A 
Published: November 2019

Abstract
The paper presents test results of the method for numerical simulation of liquid fuel spraying based on the Eulerian-Lagrangian model. This model describes the fluid flow inside the injector and directly behind it using the Euler-VOF method, while the dispersed medium (droplets) formed at a certain distance from the injector is described using the Lagrange approach. When using the VOF (volume of fluid method), the dynamical adjustment of the calculation grid at the phase interface is applied. Turbulence is modeled by the large eddy simulation (LES) method. The research results were compared with the data of direct numerical simulation (DNS) [1]. The calculation results based on the Eulerian-Lagrangian model show an acceptable agreement with the data of direct numerical simulation in terms of the main characteristics of the spraying. Thus, the structure of the two-phase flow, the parameters, and shape of the drops, as well as the speed and direction of their movement are determined qualitatively correctly.
Numerical simulation of the molten fuel relocation in fuel rod
Authors: Usov E V , Butov A A , Klimonov I A , Chuhno V I , Lobanov P D 
Published: November 2019

Abstract
Thermal destruction of fuel rods is one of the most hazardous accidents in nuclear power plants. Fuel melt contains a lot of fission products that can release and start to transport along reactor loops. Relocation of the fuel melt can change the power of reactor due to feedback between density of materials and neutron field in reactor core. The presented paper contains a brief description of the ways to simulate fuel melting and molten fuel relocation. Basic equations, numerical approximation and closing relation are presented in the paper. The results of the simulation of the molten fuel relocation as a result of the fuel rod thermal destruction are discussed.
Dynamics of the Azov-Black Sea basin by means of parallel ocean circulation modeling
Authors: Mizyuk A I , Puzina O S 
Published: November 2019

Abstract
The paper presents the methodology of free-run simulations for investigation of joint circulation of the Black and Azov Seas with high and ultra-high spatial resolution (4.5 and 1.1 km) and general characteristics of hydrophysical fields based on the results of simulations. Regional configurations used for numerical experiments are almost identical and differ only in spatial resolution with the corresponding tuning of the parameters of lateral turbulent mixing. We analyze the spatial variability of the results as well as water exchange between two basins through the Strait of Kerch. Enhancement of the resolution changes the structure of the basin circulation significantly and has to be validated using high resolution satellite data.
An adaptive PID controller with an online auto-tuning by a pretrained neural network
Authors: Chertovskikh P A , Seredkin A V , Gobyzov O A , Styuf A S , Pashkevich M G , Tokarev M P 
Published: November 2019

Abstract
This paper describes an intelligent adaptive PID controller design procedure. The controller consists of a discrete time PID and an auto-tuning neural network unit. First system identification with a nonlinear autoregressive model (NARX) was performed. This model was then used to train the neural PID tuner. A special MATLAB toolbox “SmatPID Toolbox” was developed to automate the process of controller synthesis. The resulting controller was tested in a laboratory coal-gas furnace control system to track specified air flow rates.
Small-disturbance temperature diagnostics in vortex tube with a square cross-section
Authors: Gordienko M R , Yavorsky N I , Kh Pravdina M , Polyakova V I , Ezendeeva D P , Kakaulin S V 
Published: November 2019

Abstract
The temperature diagnostics in the Ranque-Hilsh vortex was based on the scanning with the special temperature sensor of small size. The temperature profiles in different cross-sections were recorded. The temperature profiles were also measured in the swirler chamber. The difference in temperature at cold and hot outputs was about 50 ° C. Three measurement series carried out for each profile show that the temperature profiles in the Ranque tube is significantly nonstationary.
Cone nose-tip roughness effect on the transition at M=5, 6, 8
Authors: Gromyko Y V , Bountin D A , Polivanov P A , Maslov A A 
Published: November 2019

Abstract
The article presents data on the effect of distributed and isolated roughness on the blunt nose of the cone on the laminar-turbulent transition position. The experiments were performed at M=4.95, 5.95, 7.95, stagnation temperature T
0=361–465 K and stagnation pressure P
0=2–72 atm. The unit Reynolds number varied in the range Re1=(4.2–69.7)×106 m-1. The study was carried out in the boundary layer of cones with a half-angle of 7º with different zones of applying isolated and distributed roughness of the blunt nose R=5 mm. For all types of roughnesses, the effective values of Reynolds numbers are obtained, at which the transition occurs immediately after the roughness area.
Modelling the stressed state of thermal protective coating of turbine blades taking into account action forces from the gas flow
Authors: Lepeshkin A R , Nazarov V V , Ilinskaya O I , Kartavtsev A S , Guanghua Z 
Published: November 2019

Abstract
A mechanism for the destruction of a ceramic heat-protective coating of a fiber structure is proposed. The stress state of heat-protective ceramic coatings with a fiber structure of a turbine blade of an engine has been calculated taking into account the effect of forces from a gas-dynamic flow. In the calculation, the stresses in the coating fibers are determined taking into account different cases of their fixing under the action of bend from the forces of the gas-dynamic flow. The results of the calculation of the stress state of the fibers taking into account the taper are presented. The stress distributions over the height of single fibers and fibers located in the blocks of the ceramic coating when exposed to gas-dynamic forces are obtained. The estimation of the permissible thickness of the ceramic coating of the turbine blade GTE under the influence of gas-dynamic forces is resulted.
Using the copper-foam for thermal conductivity improvement of La0.9Ce0.1Ni5-alloy bed during interaction with hydrogen
Authors: Romanov I A , Borzenko V I , Kazakov A N 
Published: November 2019

Abstract
One of the main obstacles to the development of hydrogen energy is the problem of heat transfer inside metal hydride beds. Thus, the problem of increasing the metal hydride beds thermal conductivity is of great interest. This study is devoted to the investigation of the hydrogen sorption properties of an intermetallic compound placed in a matrix of foam material. Copper-foam with mass of 8 g was chosen as a matrix for 50 g of powder of activated AB5-type alloy with composition of La0.9Ce0.1Ni5. PCT-isotherms of hydrogen absorption and desorption were measured at temperatures 313, 333 and 353 K. Also, the dynamics of temperature change in the sample was studied when it was heated under vacuum conditions. The obtained data were compared with the results of previous studies conducted under the same conditions for samples of pure alloy and a mixture of alloy with copper powder. It has been concluded that the use of copper-foam to improve the thermal conductivity is promising, but it is necessary to take into account its influence on the hydrogen sorption properties of metal hydrides.
Determination of Thermophysical Parameters of the system C32-Ar
Authors: Barbin N M , Dan V P , Terentiev D I , Alekseev S G 
Published: November 2019

Abstract
In this paper, the thermophysical characteristics of the fullerene-argon (C32-Ar) system at atmospheric pressure are studied by thermodynamic modeling using the TERRA software system. Two groups of processes occurring in the system under consideration are determined: sublimation reactions with thermal dissociation and thermal dissociation reactions in the gas phase. The thermal physics of carbon vaporization in the gas phase is studied, the graphs of the dependence of the thermal characteristics of the C32-Ar system on temperature are constructed; the regularities in the inflection points of the graphs and changes in the compositions of the gas and condensed phases are revealed.
Probe supply of methane in gas-jet synthesis of diamond structures
Authors: Emelyanov A A , Yu Plotnikov M , Yudin I B 
Published: November 2019

Abstract
The present work is devoted to a numerical and experimental investigation of the probe supply of “cold” methane on the growth of diamond structures during gas-jet deposition. The analysis of results of experiments on the diamond gas-jet synthesis from methane and hydrogen mixture flows are presented. The direct simulation Monte Carlo method for numerical analysis of gas-dynamic aspect of these experiments was applied. A one-dimensional approach based on the solution of equilibrium chemical kinetics equations was used to analyze gas-phase methane decomposition. The obtained results can be useful for investigation of gas-jet deposition of diamond structures.
Influence of the substrate temperature on the jet diamond depositon
Authors: Rebrov A K , Timoshenko N I , Emelyanov A A , Yudin I B 
Published: November 2019

Abstract
The gas-jet diamond deposition with the activation of H2 + CH4 mixture by microwave discharge has been implemented. The maximum crystal size was observed at the substrate temperature of 850°C. The dependence of a film structure on the substrate temperature has been established. Diamond coating was received at a low substrate temperature (524°C).
Experimental and numerical study of the natural convection in dispersed systems in a heated rectangular cell
Authors: Tukhbatova E R , Zamula Yu S , Valiullina V I , Musin A A , Kovaleva L A 
Published: November 2019

Abstract
In this work, we study the appearance and development of convective flows in a dispersed medium by the experimental methods and mathematical modeling. An experimental study of the dynamics of thermoconvective flows is carried out in a specially designed cell, which is a rectangular vertical cavity with the possibility of heating the walls. A series of experiments were carried out at different temperature gradients. Various modes of convective flow have been obtained. To simulate the dynamics of convective flows in a rectangular cavity, a mathematical model based on the equations of thermal convection in the diffusion approximation has been created. Convective flow patterns for a dispersed medium have been obtained. Numerical calculations coincide with the experimental results. Numerical simulation of the problem allows us to estimate the distribution of velocities, temperature, and concentration of the dispersed phase inside the cell during the formation of convective flows and the established convection regime.
Synthesis of gold nanoparticles by annealing its thin film under a layer of fluoropolymer coating
Authors: Safonov A I , Starinskiy S V , Timoshenko N I 
Published: November 2019

Abstract
Gold thin films were deposited on the substrate of silicon and fused silica by method of Vacuum Gas Jet Deposition. Obtained films were coated with a fluoropolymer and annealed in a rarefied inert gas atmosphere at the temperature of 400 °C. The film morphology and composite were studied by the scanning electron microscopy. Optical properties of obtained coatings and composites were investigated. The influence of the fluoropolymer coating on formation of gold nanoparticles in the result of annealing of its thin films is established. The critical gold film thickness coated with fluoropolymer is determined, below which the presence of fluoropolymer lends to the formation of spherical nanoparticles during annealing of the composite in a studied range of parameters.
Dynamics of bubbles in liquid dielectrics under the action of an electric field: lattice Boltzmann method
Authors: Kupershtokh A L , Medvedev D A 
Published: November 2019

Abstract
The initial stage of deformation of bubbles before partial discharges under the action of the electric field is studied. The bubbles are placed on the surface of the electrode. The lattice Boltzmann method is used for 3D computer simulations of dielectric liquid dynamics. The electrostatic forces acting on a dielectric fluid in an electric field are taken into account as complete Helmholtz formula that includes the electrostriction forces. After the application of the electric field, the bubbles begin to elongate in the field direction. Above the critical value of the electrical Bond number, the bubbles can detach from the surface of the electrode and float.
Spectral characteristics of inductively coupled plasma of water vapor
Authors: Medvedev R N , Savenko R A , Churkin D S 
Published: November 2019

Abstract
The paper presents the results of experimental measurements of the emission properties of water plasma in an inductive discharge. The power of the inductive discharge was 600 W at a frequency of 27 MHz and a pressure from 0.25 to 4 mbar. Plasma temperature was estimated from the Balmer hydrogen series using relative intensities method. It is shown that in this pressure range, the plasma is not in equilibrium and the energy difference between individual excited states increased with distance from the tube axis. The plasma heating time was estimated from the dynamics of the spectral line intensities to be 200 ms.
The influence of dissipative effects on dynamic processes in a rotating electrically conductive liquid medium
Authors: Peregudin S , Peregudina E , Kholodova S 
Published: November 2019

Abstract
The present study is concerned with dynamical processes in a rotating layer of electrically conducting incompressible liquid located in a magnetic field which is parallel to the normal vector to the boundary surfaces. We take into account not only the convective terms, but also the diffusion terms in the magnetic field induction equations. This problem, as well as the geophysical hydrodynamics problem, calls for the construction of approximate variants of the principal hydromagnetic equations and rigorous mathematical analysis of these approximate equations. Moreover, advancements in the above problems depend on the approximations to be introduced. To this end, by introducing characteristic scales of variation of the variables in the original equations and estimating the magnitude orders of the terms involved in the equations, one can single out the principal and secondary terms, simplify the equations, and build a model of the process under consideration. By introduction of auxiliary functions, the system of partial differential equations is reduced to one scalar equation. This suggests the conclusion about the analytical structure of magnetohydrodynamic characteristics. From the results obtained it follows that the magnetic field generation in an electrically conducting liquid stems from the instability characterized by the corresponding relations between the gravitation force, the Coriolis force, the magnetic force, and the peculiarities of the relief topography.
Destruction of water-in-oil emulsions in electromagnetic fields
Authors: Zinnatullin R R , Kovaleva L A , Sultanguzhin R F , Gabdrafikov A F 
Published: November 2019

Abstract
In this paper, we study the degree of exposure of electromagnetic fields to water-oil emulsions with different physical and chemical properties, as well as the characteristics of their heating and delamination when exposed to radio frequency and microwave frequencies in electromagnetic fields. Experimental research methods are described. The results of experimental studies of heating emulsions in radio frequency and microwave electromagnetic fields under dynamic conditions and the results of their separation are presented. As a result of the research, it has been found that when exposed to radio frequency or microwave electromagnetic fields on oil-water emulsions, the degree of heating and the efficiency of emulsion stratification depend on the total content of asphaltene and resins, the water content in the emulsion, and the operating frequency of the generator in the region of resonant frequencies for emulsions. For all types of emulsions, radio frequency action is more effective than a microwave field, with low water contents. With increasing water content the efficiency of microwave exposure increases. Also, with an increase in the water content, the intensity of heating the emulsion in the microwave field increases with the same energy inputs.
Localization of a combined pulse discharge within a gas with a rectangular obstacle on the channel wall
Authors: Znamenskaya I A , Tatarenkova D I , Ivanov I E 
Published: November 2019

Abstract
Analysis of plasma energy redistribution was conducted on the basis of experimental study of combined volume discharge of submicrosecond duration at its initiation in a gas-dynamic flow in rectangular channel with an obstacle. Shock wave diffraction on the obstacle (parallelepiped) on the channel wall was visualized. Effects of plasma localization at upward facing step and backward facing step were experimentally discovered and studied. CFD simulation patterns of the gas dynamic non stationary flow were compared to instant flow glow images.