bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the effect of nanoparticle coatings on the transport properties of a thermostabilizer evaporator
Authors: Kuzma-Kichta Yu A , Ivanov N S , Lavrikov A V , Shtefanov Yu P , Prokopenko I F 
Published: March 2021

Abstract
In the work, porous coatings of alumina nanoparticles are investigated. The coatings were formed by various methods. The dependence of the lift height of the nanofluid on its volume was established. The properties of the coating are compared with and without microtrenches.
Modeling of radiate characteristics of dispersion phase combustion products of energy fuels
Authors: Moskalenko NI , Dodov I R , Khamidullina M S , Safiullina Ya S 
Published: March 2021

Abstract
The results of an experimental study of the optical characteristics and microstructure of the dispersed phase of the products of combustion of organic fuel in oxygen and atmospheric air are analyzed. For gaseous fuels CmHn, the concentration of soot sol increases with an increase in the ratio of elements Cm / Hn. The microstructure of soot sol strongly depends on the residence time of the combustion products in the flame zone (chemical reaction zone) and the thermodynamic temperature. The maximum ash content is observed at thermodynamic temperatures of 1500-1800K zone of chemical reactions. The minimum ash content is observed when burning fossil fuels in oxygen with a value of the coefficient of excess oxygen α = 1,03. A technique is proposed for measuring the microstructure of soot sol in atmospheric emissions of the combustion products of turbojet engines, vehicles, and power plants. The results of studies of the microstructure of the dispersed phase of fuel combustion products are used to calculate the light scattering matrices of carbon black sol according to the Mi theory. The radiation characteristics of soot sols are simulated by their superposition for different fractions i of the sol microstructure with normalization to optical density |τi| and a wavelength of λ = 0.55mkm. The optical densities |τi| for λ=0,55mkm for components i are given in numerical form depending on the height z in the combustion chamber. The radiation characteristics (absorption, scattering cross section and scattering indicatrix) are presented in the spectral region of 0.2–40mkm in the form of an electronic computer database for various gamma distributions of the carbon structure of soot sol.
Experimental Research of Thermal Processes in Hydrogen-Oxygen Air Heater for Autonomous Power Supply System
Authors: Schastlivtsev A I , Borzenko V I , Shmatov D P 
Published: March 2021

Abstract
The results of experimental studies in hydrogen-oxygen air heater for autonomous power supply system are presented. As a result of studies, it was found that the use of a stepwise air supply scheme leads to the decrease in the formation of nitrogen oxides in a wide range of operation parameters. The separation of heating and air mixing into three zones ensured a decrease in the content of nitrogen oxides in the generated air down to 4 ppm. It was found that an increase in pressure in the combustion chamber leads to an increase in the completeness of hydrogen combustion and has practically no effect on the formation of nitrogen oxides. It is shown that nitrogen molecules directly enter the combustion zone with intensive oxidation, and to reduce the formation of nitrogen oxides, air must be supplied at a distance of at least 3 cooling zones in the combustion chamber.
The Use of Nanoparticles to Displace Oil from a Porous Medium
Authors: Pakharukov Yu V , Shabiev E K , Safargaliev R F , Simonov A S , Ezdin B S , Zarvin A E , Kalyada V V 
Published: March 2021

Abstract
The formation of supramolecular structures forming a transition region at the oil-nanofluid interface with a low surface tension is studied as a result of a synergistic effect in the interaction of planar graphene nanoparticles and silicon carbide nanoparticles coated with graphene layers (Core-shell). In model experiments on a Hele-Shaw cell, it was shown that in a porous medium such hybrid nanofluids have a high displacing ability of residual oil. At the same time, the oil – nanofluid interface remains stable, without the formation of sticky fingers. In the process of research using power electron microscopy, a transition region was observed, in the structuring of which nanoparticles were directly involved. The efficiency of displacement by hybrid nanofluid depends on the concentration of nanoparticles and their interaction.
Study of radiation heat transfer during combustion of liquid fuel in a rectangular channel
Authors: Abdurakipov S , Zamashchikov A , Chesnokov E , Ronshin F , Semionov V , Vladimirov V , Dementiev Y 
Published: March 2021

Abstract
An experimental study of radiation heat transfer during combustion of a flammable liquid in a narrow rectangular channel is performed. The emission spectrum of combustion products and the absorption spectrum of butanol-1 are obtained. The case when the temperature of the combustible liquid is lower than the flash point is investigated. A comparative analysis of emission and absorption spectra shows that they do not intersect well, and the radiative heating of the liquid during diffusion flame propagation along the surface cannot be too large.
Heat transfer on a capillary-porous surface during evaporation / boiling of a thin layer of liquid at low pressures
Authors: Zhukov V I , Brester A E , Pavlenko A N , Butko A S , Shvetsov D A 
Published: March 2021

Abstract
This paper presents experimental data on heat transfer during the evaporation/boiling of n-dodecane on a surface with a capillary-porous coating in a wide pressure range. The obtained data are compared with data on heat transfer during the evaporation/boiling of n-dodecane on a smooth surface. It was found that the regime of bubble boiling occurs on a coated surface at lower pressures than on a smooth surface. It was found that enhanced heat transfer during evaporation/boiling on a capillary-porous surface as compared with a smooth surface is observed only under conditions of bubble boiling (P ≥ 103 Pa).
Heat transfer crisis investigation in a microchannel with and without nanoparticles coating
Authors: Kuzma-Kichta Yu A , Lavrikov A V , Shustov M , Kustova E A , Ivanov N S , Kuleshov E A , Kiselev A S 
Published: March 2021

Abstract
Heat transfer crisis was investigated during water boiling in a microchannel without coating and with coating of aluminum oxide nanoparticles. Experiments were performed on an advanced setup with a horizontally located microchannel with dimensions of 12.5x3x0.2 mm. Calculation of the critical heat flux in the microchannel without coating and with a coating from nanoparticles, carried out by formulas for heat transfer crisis in a horizontal pipe with microporous coating and one-sided heating. For the microchannel coated with nanoparticles the critical heat flux was calculated for the conditions of no influence of liquid subcooling and initial section. The satisfactory agreement between the experimental and calculated data was obtained. dependences of the critical heat flux from the coating thickness and characteristic size of particles were also shown. However, the data array is limited and needs to be expanded what will improve the equations for critical heat flux in a microchannel with nanoparticles coating.
Experimental study of a flow structure in coplanar channels
Authors: Terekhov V I , Zolotukhin A V , Chohar I A 
Published: March 2021

Abstract
The results of an experimental three-dimensional flow structure study in flat coplanar channels with mutually intersecting ribs on opposite walls are presented. The measurements were carried out for different angle values between ribs (2β = 60°, 90°, 120°) and Reynolds number variations. In the experiments, a two-component laser Doppler speed meter was used, which makes it possible to measure both averaged and pulsating velocity components. It is shown that a flow structure in vortex cells between ribs varies greatly from a cell location and an angle between ribs. The magnitude of hydraulic losses in coplanar channels significantly exceeds losses in smooth channels, and they increase with increasing angle between ribs.
An experience in eddy resolving simulation of mixed convection in a rotating annular cavity with one heated disk and axial throughflow
Authors: Abramov A G , Zaitsev D K , Smirnov E M , Smirnovsky A A 
Published: March 2021

Abstract
Results of numerical simulation of the flow and heat transfer in a rotating annular cavity with one heated disk and axial throughflow are presented. To assess the model effect on the solution, various vortex-resolving techniques and different computational grids have been applied. The simulation results are compared with experimental data available. Consistent with the measurements, the numerical flow analysis has revealed the presence of two pairs of cyclonic and anti-cyclonic global circulations. It has been found that all computational models tested underestimate considerably both the mean heat flux and the mean rotational velocity lag whereas the results obtained using different models are relatively close to each other.
Cross verification of a simplified model of pure steam condensation in a tube bundle using experimental and CFD-simulation data
Authors: Gubarevich T A , Klementiev A A , Minko K B , Yankov G G 
Published: March 2021

Abstract
This paper presents an analysis of a simplified model of pure steam condensation in a bundle of smooth horizontal tubes. The model was based on classical recommendations for calculating the condensation process in tube bundles. Two different approaches were used to calculate the condensation heat transfer coefficient in the model. First, the inundation effect was not considered, and the average heat transfer coefficient was calculated for condensation on a single cylinder using the Nusselt equation. Second, condensation drainage which is asymmetric to the vertical diameter of the tube was considered. The results of these calculations were verified using available experimental data. The analysis of distributions of condensation local characteristics was presented. The results of detailed CFD simulation using a previously developed author’s model was employed for additional cross-verification of closing equations used in the simplified model.
Subcooled pool film boiling heat transfer from sphere: experiment and modelling
Authors: Duplyankin R A , Glazkov V V , Ivochkin Y P , Kubrikov K G , Sinkevich O A 
Published: March 2021

Abstract

Experiments were conducted to study heat and mass transfer at film boiling on a metal sphere immersed into subcooled liquid. A model was elaborated to calculate the thickness of the vapor film and the speed of vapor flow in the film. The model also includes a detachment model for vapor bubbles lifting off the surface of the film. The model shows agreement with the results of the pool film boiling experiments with various liquids as well as for Leidenfrost drops. Quite reasonable agreement is also observed for the frequency of bubble detachment in saturated liquid. While processing the experimental data the calculations showed that the heat transfer into the bulk of liquid from vapor-liquid boundary is much more intense than expected. The effect is not determined solely by natural convection within the liquid as the heat flows determined by natural convection are two orders of magnitude less than those obtained. An attempt was made to determine the consequent heat transfer coefficient based upon experimental data for the frequency of bubble detachment from off the vapor film around the sphere. The abnormally high heat transfer detected could be important in practical applications.
Numerical solution of the conjugate heat transfer problem for turbulent liquid flow in a tube using the large eddy simulation method
Authors: Artemov V I , Makarov M V , Yankov G G , Minko K B 
Published: March 2021

Abstract
This article presents the results of turbulent flow and temperature fluctuations simulation in the liquid and the tube wall in a conjugate formulation using the hybrid Reynolds-averaged Navier-Stokes / large eddy simulation (RANS/LES) method. Calculations are performed for water, air and mercury. The results show that the “conjugate” LES model implemented in in-house CFD code ANES provides a good reproduction of the available experimental results on temperature fluctuations near the wall for cases of different wall thicknesses and thermal activity of the wall material and the fluid. An approximate model for the wall is proposed and can be used as a boundary condition for calculations by direct numerical simulation (DNS) and LES methods in the non-conjugate formulations.
Calculation of critical heat fluxes at boiling on microstructured surfaces
Authors: Stupakova AV , Dedov AV 
Published: March 2021

Abstract
A method for increasing the critical heat flux at boiling by applying porous structures of various regular geometries to a smooth surface is considered. The analysis of experimental data and calculation of the critical heat flux based on the model of V.V. Yagov, which considers the additional inflow of liquid into the evaporation zone due to the action of capillary forces in a porous space. Comparison of experimental and calculated data allows us to conclude that this model is not suitable for all microstructured surfaces.
Investigation of heat transfer during cooling of a high-temperature target by a dispersed coolant flow
Authors: Komov A T , Sherbakov P P , Zakharenkov A V , Smorchkova Yu V , Ilyin V V , Shteling V S , Sherbakov S P 
Published: March 2021

Abstract
An experimental study of the heat flux density and the heat transfer coefficient during cooling of a high-temperature surface by a dispersed liquid flow has been carried out. The results of an experimental study on the possibility of removal heat fluxes of high density and thermal stabilization of an energy-loaded surface are obtained. Experimental data were obtained with stationary heat transfer in the following range of operating parameters of the coolant: water pressure 0.2 ÷ 0.4 MPa, mass flow rate of water 0.0033 ÷ 0.015 kg / s; induction heating power 7 ÷ 20 kW.
Some results of the study of heat transfer during the cooling of the high-temperature surface of the working section by the dispersed flow of the coolant
Authors: Demidov A S , Tupotilov I A , Zakharenkov A V , Loktionov V D , Dedov A V 
Published: March 2021

Abstract
In this paper investigates the heat exchange of the high-temperature surface of the working area during cooling by a dispersed two-component flow. A brief description of the experimental stand, the working section of the spraying device for creating a dispersed flow is given. The results of experimental modeling of the cooling of the working section at different regime parameters of the flow and supplied electric powers are presented. Data on the distribution of the wall temperature along the length of the heated working section are obtained. The thermal flux density on the side surface of the working area was estimated based on the readings of thermocouples in the work area. The operating parameters of the coolant at which the sample is cooled most effectively are determined.
Electron parameters in a hollow cathode discharge plasma in He and He:H2O mixture
Authors: Andreev S N , Bernatskiy A V , Dyatko N A , Ochkin V N 
Published: March 2021

Abstract
The electron energy distribution functions (EEDFs) were measured in the discharge plasma in pure helium and in helium with the addition of water vapor He:H2O (2:1). The studies were carried out in the discharge gap between the rectangular hollow cathode and the mesh anode using the original probe measurement system. It was established, in particular, that the EEDF in He had pronounced maxima in the regions of ∼4 eV and ∼15 eV, while in the He:H2O mixture there was no local maximum in the high-energy region. The EEDF calculations in the local approximation for experimental conditions were performed. It turned out that the calculated distribution functions differ noticeably from the measured ones. The possible physical causes leading to the discrepancy between the measured and calculated EEDFs were discussed.
Quantitative elastic peak electron spectroscopy
Authors: Afanas’ev V P , Kaplya P S , Lobanova L G 
Published: March 2021

Abstract
New quantitative method of hydrogen isotopes detection in engineering materials used for fusion is introduced. The study proposes a theory of small-angle atomic particle elastic reflection from multicomponent materials. A method for interpreting Elastic Peak Electron Spectroscopy signals considering the multiple scattering effect was developed. It is shown that ignoring the multiple scattering effect results in significant errors with quantitative evaluation of Elastic Peak Electron Spectroscopy signals.
RF-heating system of helicon-type for PLM-2 plasma device: design parameters
Authors: V Tran Quang , Iachuk V A , Budaev V P , Fedorovich S D 
Published: March 2021

Abstract
The PLM-2 linear magnetic plasma device is for steady-state stationary hours-long plasma confinement with parameters providing the relevant fusion reactor plasma loads on materials. The machine is designed both for fundamental studies of plasma-surface interactions under high heat and particle fluxes, and as a high-heat flux facility for the tests of plasma-facing components under realistic plasma conditions. In the PLM-2 plasma device, a plasma heating ICR system will be created using a helicon antenna. Production of plasma by using helicon waves is known as helicon discharge, and the plasma produced by using the helicon discharge has a totally distinct character where the enhancement of the plasma parameters takes place at particular conditions. Helicon discharges produce higher density plasma at a comparatively lower given input power than any other RF or DC discharges, and also the plasma is least contaminated due to the presence of the antenna out-side the chamber.
Experimental investigation of thermal expansion of niobium at high temperatures
Authors: Senchenko V N , Belikov R S 
Published: March 2021

Abstract
Experimental study of thermal expansion of niobium by millisecond pulse heating technique was performed. Using this technique, an experimental determination of the temperature dependence of thermal expansion coefficient, electrical resistivity, enthalpy and specific heat capacity at premelting region for niobium have been carried out. The results obtained allow calculating the density of Nb in the wide range of high temperatures up to the melting point.
Determination of the thermophysical characterisitics of the Moon soil with depthed thermoprobes
Authors: Dudkin K K , Alifanov O M , Babaitsev A V 
Published: March 2021

Abstract
Determination of thermophysical characteristics of the lunar soil is an important scientific task. This article examined three options for penetrating thermal probe design for measuring the thermal properties of soil. A numerical simulation was carried out, and revealed distortion of temperature distribution, which can be caused by design of the thermal probe and affect the measurements, was studied,. The first scheme is a rod thermal probe, which is similar to the thermal probe used in Apollo missions. The second scheme is an improved rod thermal probe, with a detachable heater with an autonomous power source at the lower end of the rod. The third scheme is a more complicated design made by a series of autonomous heaters and temperature sensors that are fixed in a pre-drilled well and have no thermal connection. According to the calculation results, the rod thermal probe used in the Apollo missions and the thermal probe with a detachable heater showed the same level of temperature distribution distortion. The influence of the design of the split thermal probe was by 30% lower. The last type of the probe may allow to improve the accuracy of measurements of the TPC of the lunar soil.
Automated system for calculation thermophysical properties of important for power engineering substances
Authors: Vasserman A A , Malchevsky V P 
Published: March 2021

Abstract
Data on thermodynamic and transport properties of gases and liquids are necessary for many branches of science and technology. Such data are required in different systems of independent variables and in a wide range of values of these variables for design and study of various plants. Reliable sources of information on the properties of substances and materials are data banks and automated information systems. Recently, a large number of automated systems have been created in the world that are designed to solve various applied problems. In this work is described the system that we developed, which is designed to calculate the values of the thermophysical properties of a number of substances important for power engineering.
Research of oxygen-conducting ceramic materials for lithium chloride melt in reactors for pyrochemical processing of spent nuclear fuel
Authors: Valtseva A I , Pershin P S , Suzdaltsev A V , Zaikov Yu P 
Published: March 2021

Abstract
The behavior of potential ceramic materials (electrolytes conducting on oxygen ions) of electrochemical control devices of technological operations in oxide-halide melts was investigated. Based on the literature data and thermodynamic estimates for long-term tests in the LiCl, LiCl-Li2O and LiCl-Li2O-Li melts at a temperature of 650 ° C, mixtures of oxides ZrO2-Y2O3 (YSZ), ZrO2-Sc2O3 (ScSZ), ZrO2-CaO (CaSZ) and CeO2-Gd2O3 (CGO) were selected. These melt under the studies are the most widely used in a number of high-temperature electrochemical processes of obtaining metals and alloys, as well as in the developed schemes of pyrochemical processing of nuclear fuel. The stability of the samples was determined by changes in mass, appearance, elemental analysis of the melt, as well as via the scanning electron microscopy. The best stability in LiCl-Li2O melts was shown by the samples of ZrO2-Y2O3 with cubic and tetragonal structures and the samples of ZrO2-CaO. Based on the changes in the microstructure of the samples, it was concluded that the increase in the content of Li2O in the LiCl-Li2O melt accelerates the destruction of the sample mainly by the mechanism of dyeing, and the presence of lithium leads to loosening of the samples.
Thermal Coefficients of the Water–Aliphatic Alcohol Binary System
Authors: Osmanova B K , Bazaev A R , Bazaev E A 
Published: March 2021

AbstractThe results of thermal coefficients calculations (кT, α, β) of water–aliphatic alcohol (methanol, ethanol, 1-propanol) systems of different compositions (x=0.2, 0.5, 0.8 mole fractions of alcohol) in liquid and vapor phases, as well as at critical and supercritical regions of state parameters have been presented. The dependence of values of thermal coefficients from density temperature and composition at different states is shown. The calculations are based on the polynomial equation of state, represented by expansion of the compressibility factor into a power series of reduced density (ω=ρ/ρcr) and reduced temperature(τ=T/Tcr):Z=1+∑i=1m∑j=0niaijωi/τj. The mean percentage errors of the calculated pressure values relative to the experimental values depending on system and number of carbon atom is varied 0.6-3.3%.
Substantiation of using uranium-zirconium carbonitride as kernel for microspherical fuel
Authors: Bakhin A N , Bespechalov B N , Vishnevsky V Yu , Zaitsev D A , Kiselev D S , Kozlov V V , Kotov A Yu , Marushkin D V , Repnikov V M 
Published: March 2021

Abstract
The paper presents an alternative design of the micro fuel element with the use of a core made of uranium-zirconium carbonitride fuel instead of traditional uranium dioxide which has a detrimental effect on the micro fuel element operation due to oxygen. This fuel as part of the four-layer TRISO-micro fuel element creates significantly lower gas pressure under the coating, it is compatible well with a pyrocarbon coating and does not crack it. The fuel has high thermal properties and it is much less subject to the “amoeba”-effect.