HEAT AND MASS TRANSFER IN COMBUSTION PROCESSES
SIMULATION OF THE COMBUSTION OF THIN IRON RODS IN OXYGEN IN THE ADIABATIC APPROXIMATION
UDC 536.46
S. I. Shabunya,a V. V. Martynenko,a V. I. Ignatenko,a and J.-Ch. Rostaingb
A mathematical model of the combustion of a thin iron rod in the atmosphere of oxygen with no forced air fl ow around it has been constructed. This model includes an adjustment parameter that relates the rate of combustion of the rod with its diameter and the content of oxygen. The problem on the combustion of a thin iron rod in oxygen was solved analytically in the adiabatic approximation. The results of calculations were compared with the corresponding experimental data.
Keywords: combustion of metals, effective heat-conductivity coeffi cient, oxygen-transfer coeffi cient, adiabatic approximation.
PAGE 1227.
aA. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 15 P. Brovka Str., Minsk, 220072, Belarus; email: ; bAirLiquide, Claude-Delorme Research Center Paris-Saclay, 1, Chemin de la Porte des Loges, BP 126, 78354, Les Loges-en-Josas, Cedex, France; email: Jean-Christophe.Rostaing@AirLiquide. com. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1227–1237, November–December, 2014. Original article submitted June 24, 2014.
MEASUREMENT OF IGNITION LIMITS AND INDUCTION TIMES OF HYDROGEN–AIR MIXTURES BEHIND THE INCIDENT SHOCK WAVE FRONT AT LOW TEMPERATURES
UDC 541.126:127; 539.46
V. A. Pavlov and G. Ya. Gerasimov
We have made an experimental study of the ignition of a stoichiometric hydrogen–air mixture behind the incident shock wave front in a shock tube. The ignition limits and the induction times of the mixture behind the wave front in the range of temperatures T = 550–960 K and pressures P = 0.01–1.1 MPa have been determined. Much lower values of the ignition temperature compared to the experimental results obtained in refl ected shock waves, as well as to the classical Lewis and Elbe, have been registered. The measured induction times in the above temperature and pressure ranges are in good agreement with theoretical estimates.
Keywords: hydrogen–air mixtures, combustion, ignition limits, induction time, incident shock wave.
PAGE 1238.
Institute of Mechanics, M. V. Lomonosov Moscow State University, 1 Michurinskii Ave., Moscow, 119192, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1238–1244, November– December, 2014. Original article submitted May 28, 2014.
MATHEMATICAL MODELING OF CATALYTIC OXIDATION OF METHANE IN A CHANNEL WITH A POROUS INSERT
UDC 519.87:66.096.5
O. V. Matvienko,a A. I. Baigulova,a and A. M. Bubenchikovb
Results of investigations of the structure and chemical reaction of a swirling fl ow in a cylindrical channel with a porous end insert have been presented. The performed analysis shows that for the characteristics of chemical transformation in a catalytic reactor to be improved, it is necessary to organize fl ow so as to decrease its mean-fl owrate velocity in the reactor at a prescribed rate of fl ow and to ensure as uniform as possible radial distribution of the axial velocity.
Keywords: catalytic oxidation, physicochemical hydrodynamics, methane–air mixture, swirling fl ows, computational hydrodynamics.
PAGE 1245.
aTomsk State University of Architecture and Civil Engineering, 2 Solyanaya Ave., Tomsk, 634003, Russia; bTomsk State University, 36 Lenin Ave., Tomsk, 634036, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1245–1260, November–December, 2014. Original article submitted June 3, 2014.
INFLUENCE OF THE STRUCTURE OF A SOLID-FUEL MIXTURE ON THE THERMAL EFFICIENCY OF THE COMBUSTION CHAMBER OF AN ENGINE SYSTEM
UDC 662.612.2, 662.311.1
S. I. Futko, I. A. Koznacheev, and E. M. Ermolaeva
On the basis of thermodynamic calculations, the features of the combustion of a solid-fuel mixture based on the glycidyl azide polymer were investigated, the thermal cycle of the combustion chamber of a model engine system was analyzed, and the effi ciency of this chamber was determined for a wide range of pressures in it and different ratios between the components of the combustible mixture. It was established that, when the pressure in the combustion chamber of an engine system increases, two maxima arise successively on the dependence of the thermal effi ciency of the chamber on the weight fractions of the components of the combustible mixture and that the fi rst maximum shifts to the side of smaller concentrations of the glycidyl azide polymer with increase in the pressure in the chamber; the position of the second maximum is independent of this pressure, coincides with the minimum on the dependence of the rate of combustion of the mixture, and corresponds to the point of its structural phase transition at which the mole fractions of the carbon and oxygen atoms in the mixture are equal. The results obtained were interpreted on the basis of the Le-Chatelier principle.
Keywords: solid-fuel mixture, glycidyl azide polymer, miniengine, microelectromechanical system, engine system, thermal effi ciency, phase-transition point, thermal cycle, cyclic process, Le-Chatelier principle..
PAGE 1261
A. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 15 P. Brovka Str., Minsk, 220072, Belarus; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1261–1268, November–December, 2014. Original article submitted August 15, 2014.
HEAT AND MASS TRANSFER IN DISPERSED AND POROUS MEDIA
FEATURES OF FILTRATION IN LOW-PERMEABILITY TRAPS
WITH A LIMITING GRADIENT
UDC 532.546
B. Sh. Shagapov,a,b O. V. Belova,b and A. Ya. Davletbaevc
With account for the nonlinear effects observed in experiments with low-permeability pools at low pressure gradients of the order of 105 Pa/m, a refi nement of the Darcy law is proposed. On the basis of such a model a number of problems describing the infl ow of the liquid to the well have been solved.
Keywords: two-liquid model, Darcy laine particles.
PAGE 1269
aInstitute of Mechanics, Ufa Science Center, Russian Academy of Sciences, 71 Oktyabrya Ave., Ufa, 450054, Bashkortostan, Russia; email: ; bBirsk Branch of the Bashkir State University, 10 Internatsional′naya Str., 452450, Bashkortostan, Russia; email: ; cBashkir State University, 32 Zaki Validi Str., Ufa, 450074, Bashkortostan, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1269–1281, November–December, 2014. Original article submitted March 5, 2014.
MATHEMATICAL SIMULATION OF TWO-PHASE LIQUID MOTION IN CONCENTRICALLY DISPOSED COMMUNICATING PIPES
UDC 532.546
É. M. Abbasov and S. A. Imamaliev
The infl uence of various kinds of elastic waves produced at the well mouth on the character of change in the bottomhole pressure is studied theoretically with account for the two-phase character of the liquid. The dependence of the bottom-hole pressure dynamics on the phase concentration of sand has been determined.
Keywords: two-phase liquid, oil well, Rakhmatulin′s model.
PAGE 1282
Scientifi c-Research and Design Institute "Neftegaz," 88a Zardabi Ave., Baku, Az1012, Azerbaijan; email: aelhan@ mail.ru. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1269–1281, November–December, 2014. Original article submitted April 24, 2014.
ISOTHERMAL FILLING OF A MOLDING CAVITY WITH SIMULTANEOUS IMPREGNATION OF A POROUS LAYER
UDC 532.135:536.242.678:065
A. V. Baranova and O. Kh. Dakhinb
A study is made of isothermal fi lling of a planar cavity with a non-Newtonian fl uid with simultaneous impregnation of a porous layer. The cavity fl ow is described by the inertialess Navier–Stokes equations, the porous layer fl ow by the Darcy equation, and the fl ow in the region adjoining the fl uid–porous layer interface is described by the Brinkman equation.
Keywords: Newtonian liquid, shear fl ow, impregnation, molding.
PAGE 1290
aI. M. Gubkin Russian State University of Oil and Gas, 65 Leningradskii Ave., Moscow, 119296, Russia; email: ; bVolgograd State Technical University, 28 Lenin Ave., Volgograd, 400131, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1290–1296, November–December, 2014. Original article submitted June 4, 2014.
MECHANISM OF LIQUID DROP DEFORMATION IN SUBSONIC MOTION IN A GASEOUS MEDIUM
UDC 536.4
R. S. Volkov, A. O. Zhdanova, O. V. Vysokomornaya, G. V. Kuznetsov, and P. A. Strizhak
We have made experimental studies of the processes of deformation of drops (of size up to 6 mm) of three liquids with different physical properties (water, ethanol, kerosene) in motion in a gaseous medium (air) with velocities of up to 5 m/s. The most typical forms of drops have been distinguished, and the cyclic character of their change in traveling in a gaseous medium to distances of up to 1 m has been established. The characteristic "deformation cycles" in the process of motion have been determined, and the time intervals of the form change within each "deformation cycle" have been established. The maximum deviations of drop sizes from the initial ones have been calculated, and the infl uence of their sizes and velocities on the basic characteristics of the deformation have been determined.
Keywords: drop water, kerosene, ethanol, deformation, "deformation cycle," form, sphere, ellipsoid.
PAGE 1297 ,
Tomsk National Research University, Energy Institute, 30 Lenin Ave., Tomsk, 634050, Russia; email: romanvolkov@ tpu.ru; . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1297–1307, November– December, 2014. Original article submitted July 7, 2014.
UDC 66.047.37
REGULAR HEAT REGIME OF HEATING OF MOIST CAPILLARY-POROUS MATERIALS IN THE PROCESS OF THEIR DRYING
A. I. Ol'shanskii
Results of investigation of the drying of plane samples of different capillary-porous materials by the method of regular heat regime are presented. Experimental empirical dependences defi ning the kinetics of drying of these materials have been obtained. The dependences of the rate of heating of a moist capillary-porous material and the rate of decrease in the moisture content in it on different factors determining the drying process were investigated. The infl uence of these factors on the rate of heating of such a material and the rate of removal of moisture from it were determined.
Keywords: rate of heating of a moist material, coeffi cients of heat exchange, thermal diffusivity, and inhomogeneity of the temperature distribution in a material, mean-integral temperature, relative moisture content.
PAGE 1308
Vitebsk State Technological University, 72 Moskovskii Ave., Vitebsk, 210035, Belarus; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1308–1318, November–December, 2014. Original article submitted January 14, 2014.
THERMOPHYSICAL PROPERTIES
MODEL OF THE STRUCTURE OF FIBROUS HEAT-INSULATING MATERIALS FOR ANALYZING COMBINED HEAT TRANSFER PROCESSES
UDC 536.21:536.33
A. V. Zueva and P. V. Prosuntsovb
A numerical algorithm is proposed for evaluation of the parameters of a fractured porous bed from the results of hydrodynamic well testing based on the Levenberg–Marquardt method which belongs to the methods of minimization of second order. The algorithm makes it possible to evaluate such parameters of the bed as the permeability coeffi cient of wells, the parameter of fl uid crossfl ow between blocks and wells, the characteristic delay time, the linear dimension of the blocks of the rock matrix, the piezoconductivity coeffi cient of the bed, the pressure in the bed, and the production index of the well.
Keywords: identifi cation, fractured porous bed, inverse problem, regularization, minimization methods, scaling..
PAGE 1319
Federal State Budget-Funded Institution of Science "Institute of Mechanics and Mechanical Engineering" of the Kazan Scientifi c Center of the Russian Academy of Sciences, 2/31 Lobachevskii Str., Kazan, 420111, Russia; email: , . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1349– 1355, November–December, 2014. Original article submitted May 30, 2014.
INCREASING THE THERMAL CONDUCTIVITY AND THERMAL DIFFUSIVITY OF ASBESTOS-REINFORCED LAMINATES THROUGH MODIFICATION
OF THEIR POLYMER MATRIX WITH CARBON NANOMATERIALS
UDC 536.2.083
S. M. Danilova-Tret′yak, L. E. Evseeva, and S. A. Tanaeva
Experimental investigations of the thermophysical properties of traditional and modifi ed asbestos-reinforced
laminates depending on the type of their carbon nanofi ller have been carried out in the range of temperatures from
–150 to 150oC. It has been shown that the largest (nearly twofold) increase in the thermal-conductivity and thermaldiffusivity
coeffi cients of the indicated materials is observed when they are modifi ed with a small-scale fraction of
a nanofi ller (carbon nanotubes). The specifi c heats of the modifi ed and traditional asbestos-reinforced laminates
turned out to be identical, in practice, within the measurement error.
Keywords: thermal conductivity, thermal diffusivity, specifi c heat, carbon nanomaterials, fabric-based laminates.
INFLUENCE OF SAMPLE DIMENSIONS ON ERRORS IN DETERMINING THE THERMAL DIFFUSIVITY OF SEMITRANSPARENT SEMICONDUCTING
MATERIALS BY THE LASER-PULSE METHOD
UDC 536.2.083
G. V. Kuznetsov and M. D. Kats
An analysis has been made of the errors in determining the thermal diffusivity of a typical semiconducting material,
i.e., germanium, due to the radiative transfer of energy in the heated layer of the material under the conditions that
correspond to the implementation of the laser-pulse method when the material′s surface is exposed to a collimated
fi nite-length laser pulse. The infl uence of the geometric dimensions of a sample and of the process of radiation
absorption on the value of this error has been established.
Keywords: thermal diffusivity, germanium, laser-pulse method, methodological errors, thickness and radius of a sample, numerical solution, coeffi cient of radiation absorption.
National Research Tomsk Polytechnic University, Institute of Power Engineering, 30 Lenin Ave., Tomsk, 643050, Russia; email: , . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1335– 1340, November–December, 2014. Original article submitted April 29, 2014.
EVALUATION OF RANDOM ERRORS OF THE MULTIMODEL METHOD OF NONDESTRUCTIVE DETERMINATION OF THE THERMOPHYSICAL PROPERTIES
OF SOLID MATERIALS
UDC 536.2.08
N. P. Zhukov, N. F. Mainikova, I. V. Rogov, and A. O. Antonov
We present the results of an analysis of random errors incurring in the multimodel method of nondestructive determination of the thermophysical properties of solid materials. We have formulated recommendations for decreasing these errors by means of selecting operational and design parameters of a measuring device used for
implementing the aforementioned method.
Keywords: solid materials, thermal analysis, thermophysical properties, nondestructive control, random errors.
Tambov State Technical University, 106 Sovetskaya Str., Tambov, 392620, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1341–1348, November–December, 2014. Original article submitted September 24, 2013.
EVALUATION OF PARAMETERS OF A FRACTURED POROUS BED FROM DATA ON UNSTEADY FLUID INFLOW TO VERTICAL WELLS
UDC 532.546
R. V. Sadovnikov
A numerical algorithm is proposed for evaluation of the parameters of a fractured porous bed from the results of
hydrodynamic well testing based on the Levenberg–Marquardt method which belongs to the methods of minimization
of second order. The algorithm makes it possible to evaluate such parameters of the bed as the permeability
coeffi cient of wells, the parameter of fl uid crossfl ow between blocks and wells, the characteristic delay time, the
linear dimension of the blocks of the rock matrix, the piezoconductivity coeffi cient of the bed, the pressure in the bed,
and the production index of the well.
Keywords: identifi cation, fractured porous bed, inverse problem, regularization, minimization methods, scaling.
Federal State Budget-Funded Institution of Science "Institute of Mechanics and Mechanical Engineering" of the Kazan Scientifi c Center of the Russian Academy of Sciences, 2/31 Lobachevskii Str., Kazan, 420111, Russia; email: , . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1349– 1355, November–December, 2014. Original article submitted May 30, 2014.
HEAT AND MASS TRANSFER IN PHASE TRANSFORMATIONS
MODELING OF THE EVAPORATIVE COOLING OF RUNNING-DOWN LIQUID FILMS IN THE SLIT CHANNEL OF THE SPRAYING DEVICE OF A COOLING TOWER
UDC 536.24
G. V. Dashkov, G. L. Malenko, A. D. Solodukhin, and V. D. Tyutyuma
This paper presents the results of computational modeling of the nonstationary evaporative cooling of a liquid fi lm running down a vertical surface cooled by a turbulent vapor-air counterfl ow. The heat and mass transfer problem has been formulated in conjugate form. The calculation data on the total heat fl ow density at the interface for various instants of time are given.
Keywords: evaporative heating, running-down fi lm, slit channel, spraying device, cooling tower.
PAGE 1356
A.V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 15 P. Brovka Str., Minsk, 220072, Belarus; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1356–1361, November–December, 2014. Original article submitted June 17, 2014.
BOILING OF VARIOUS LIQUIDS ON MICROSTRUCTURIZED SURFACES
UDC 536.24
I. A. Popov and A. V. Shchelchkov
This paper presents the results of experimental studies of the heat transfer of microstructurized surfaces of various confi gurations and sizes obtained by the method of deforming cutting. It has been shown that the intensity of heat transfer on such surfaces with three-dimensional columnar and channel structures increases by 20 times, and on microfi nned surfaces by 2.5 times, compared to the smooth boiling surface. The critical heat fl ow density increases 4.1–6 times thereby. The obtained results on the heat transfer on the above surfaces and the critical fl ow densities on them can be used for calculating the heat transfer coeffi cients and the heat loads in boiling of various saturated liquids on such surfaces with sizes of fi n elements from 50 to 420 μm at a pressure of 0.1 MPa under free convection conditions.
Keywords: microstructurized surface, boiling crisis, heat transfer enhancement.
PAGE 1362
A. N. Tupolev Kazan′ National Research Technical University — KAI, 10 K. Marx Str., Kazan′, 420111, Tatarstan, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1362–1374, November– December, 2014. Original article submitted April 8, 2014.
HEAT CONDUCTION AND HEAT TRANSFER IN TECHNOLOGICAL PROCESSES
COMPUTATIONAL MODELING OF THE TEMPERATURE REGIME IN A ROOM WITH A TWO-PANEL RADIATOR
UDC 697.12
B. I. Basok,a B. V. Davydenko,a G. G. Farenuyk,b and S. M. Goncharuka
By the method of computational modeling the velocity and temperature fi elds in a room heated by a two-panel radiator have been investigated. The features of the air-temperature regime of the room with the above heating system have been considered.
Keywords: temperature regime of the room, computational modeling, heat transfer.
PAGE 1375
aInstitute of Technical Thermal Physics, National Academy of Sciences of Ukraine, 2a Zhelyabov Str., Kiev, 03057, Ukraine; email: basok@ittf. kiev.ua, ; bGP "State Research Institute of Building Constructions," 5/2 Ivan Klimenko Str., Kiev, 03680, Ukraine; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1375–1379, November–December, 2014. Original article submitted April 17, 2014.
NUMERICAL INVESTIGATION OF HEAT TRANSFER IN SOIL UNDER THE ACTION OF A LOCAL IGNITION SOURCE IN A TWO-DIMENSIONAL FORMULATION
UDC 536.4
N. V. Baranovskii and A. É. Ni
Forest fi res have an adverse effect on soils. The so-called pyrogenic soils can be formed. In this paper, we have modeled mathematically unsteady conductive heat transfer in soil under the action of a local ignition source. Physical and mathematical models of heat transfer in the layer structure of soil have been developed. Temperature fi elds at different instants of time, the one-dimensional temperature distribution over the soil cross section, and also the dependence of the temperature on time at a characteristic point of the soil have been obtained as a result of numerical investigation. Further advance of the present scientifi c line can provide a fundamental basis for development of information and computation systems of environmental monitoring of soils during fi re-hazardous seasons.
Keywords: forest fi re, mathematical modeling, heat transfer, soil.
PAGE 1380
National Research Tomsk Polytechnic University, 30 Lenin Ave., Tomsk, 634050, Russia; email: fi redanger@narod. ru. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1380–1386, November–December, 2014. Original article submitted July 2, 2014. ,br>
HEAT EXCHANGE BETWEEN A LIQUID FLOWING IN A TUBE AND AN EXTERNAL FLOW AROUND IT WITH INTENSE STIRRING
UDC 66.040.2:533.6.011.6
A. I. Moshinskii
A mathematical model of heat exchange between a tube (a coil) with a liquid fl owing inside it and an external fl ow around it is considered. Limiting equations of the process with intense stirring are derived. Some solutions of the proposed equations are obtained that can be used in modeling the processes occurring in heat exchangers.
Keywords: heat exchange, heat exchanger, heat-transfer agent, stirring, displacement.
PAGE 1387
St. Petersburg Pharmaceutical Chemistry Academy, 14 Prof. Popov Str., St. Petersburg, 193376, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1387–1397, November– December, 2014. Original article submitted March 17, 2014.
HYDROGASDYNAMICS IN TECHNOLOGICAL PROCESSES
MODIFIED MATHEMATICAL MODEL OF A "FROZEN" GAS SUSPENSION
UDC 532.525
N. L. Klinacheva, Yu. M. Kovalev, and V. F. Kuropatenko
An analysis has been made of the invariance of a widely used mathematical model of a "frozen" gas suspension with respect to the Galilean transformation. It has been shown that the equations of this model are not invariant with respect to the Galilean transformation, which results in a fi ctitious source term in the energy equation. Additional entropy increase leads to a violation of the second law of thermodynamics. In this work, the authors have proposed a modifi cation of the "frozen"-gas-suspension model that leads to its invariance with respect to the Galilean transformation. Calculations have been performed and comparisons with an invariant model have been made.
Keywords: mathematical model, invariance, multicomponent mixture.
PAGE 1398
South-Ural State University (National Research University), 76 Lenin Ave., Chelyabinsk, 454080, Russia; email: , . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1398– 1403, November–December, 2014. Original article submitted March 14, 2014.
LATENT WAVES IN HETEROGENEOUS MEDIA
UDC 532.629.5
V. S. Surov
The dynamics of latent waves, i.e., their refl ection from a solid side and interaction with each other, has been investigated numerically within the framework of the heterogeneous-medium model with a gasdynamic core.
Keywords: multivelocity multicomponent medium, hyperbolic systems of equations, latent waves, numerical simulation.
PAGE 1404
South-Ural State University, 76 Lenin Ave., Chelyabinsk, 454080, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1404–1408, November–December, 2014. Original article submitted February 25, 2014.
DYNAMICS OF THE WORKING MEDIUM OF A DIFFUSION-COOLED ELECTRIC-DISCHARGE CO2 LASER WITH PERIODIC HEAT RELEASE IN THE AXIAL REGION OF ITS CYLINDRICAL RESONATOR
UDC 519.63:534.1
V. V. Azharonoka and A. L. Tukmakovb
The dynamics of the gas mixture in the cylindrical resonator of a CO2 laser with periodic heat release in the region of its axis was defi ned on the basis of the numerical solution of the system of Navier–Stokes equations by the explicit MacCormack method with splitting of the initial operator in space directions. The space fi elds of the gas-dynamic functions of the gas mixture and the ranges of their change were determined, and the character of the averaged fl ow of this mixture was investigated.
Keywords: Navier–Stokes equations, explicit MacCormack scheme, acoustic resonator, averaged fl ow.
PAGE 1409
aInstitute of Physics of the National Academy of Sciences of Belarus, 68 Nezavisimost' Ave., Minsk, 220072, Belarus; email: ; bA. N. Tupolev Kazan National Research Technical University, 10 K. Marks Str., Kazan, 420111, Russia; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1409–1418, November–December, 2014. Original article submitted March 21, 2014.
ON A HYDRODYNAMIC SOURCE OF SELF-EXCITATION OF NARROW-BAND DISTURBANCES IN A WIND TUNNEL
UDC 532.526.3;532.527;532.559.3
R. K. Karavosov and A. G. Prozorov
A study has been made of the occurrence of intense narrow-band components in the spectra of pressure pulsations in a wind tunnel. It has been established that the high level of acoustic emission in auto-oscillations is a consequence of negative static-pressure gradients inside the nozzle and the change in the regime of wall shear fl ow of an incompressible medium, of the formation of large-scale coherent structures, and of resonance phenomena. It has been noted that the azimuthally nonuniform topology of large-scale transient-fl ow structures emitting sound and implementation of not a single resonance are responsible for the existence of ensembles of components of an undesirably high level in the pressure-pulsation spectra in the tunnel. One possible method of fi ghting the considered sound emission generating
auto-oscillations has been indicated.
PAGE 1419
GENERALIZED RAYLEIGH EQUATION FOR THE BUBBLE DYNAMICS IN A TUBE
UDC 536.248.2.001.5
Yu. B. Zudin, N. Sh. Isakov, and V. V. Zenin
The derivation of the generalized Rayleigh equation that describes the dynamics of a spherical gas bubble in a tube fi lled with an ideal liquid is given. Its solution has spherical (the classical Rayleigh equation) and cylindrical (the case of a long tube) asymptotics. An exact analytical solution of the problem on vapor bubble collapse in a long tube
has been obtained.
Keywords: generalized Rayleigh equation, spherical gas bubble, ideal liquid.
PAGE 1398
National Research Center "Kurchatov Institute," 1 Acad. Kurchatov Ave., Moscow, 123098, Russia; email: yzudin@ gmail.com. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1425–1430, November–December, 2014. Original article submitted June 9, 2014.
TRANSIENT NATURAL CONVECTION FLOW WITH COSINUSOIDALLY FLUCTUATING THERMAL AND MASS DIFFUSION
UDC 536.2
P. K. Sharmaa and S. K. Sainib
The problem of a transient natural convection fl ow of a viscous incompressible fl uid past a permeable (porous) fl at plate with the temperature and concentration cosinusoidally fl uctuating with time is considered. The equations of mass, momentum, and energy conservation that govern the heat and mass transfer problem are solved analytically
with the use of the regular perturbation technique. Explicit expressions for the velocity, temperature, and concentration are obtained. Numerical evaluation of the analytical results is performed, and graphical results for the fl ow characteristics, skin friction, and the rate of heat transfer are presented and discussed.
Keywords: spanwise cosinusoidally fl uctuating temperature and concentration, skin friction, heat transfer, natural
convection flow.
PAGE 1431
aDepartment of Applied Mathematics, Amity School of Engineering and Technology, New-Delhi-110061, India; email: ; bDepartment of Mathematics, Shri Venkateshwara University, Gajraula, Amroha, Utter Pradesh-244236, India. Published in Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1431–1439, November–December, 2014. Original article submitted September 13, 2013.
FULLY DEVELOPED TURBULENT TAYLOR–COUETTE FLOW
UDC 532.542
V. A. Babkin
Within the framework of the model of anisotropic near-well turbulence, an approximate analytical solution is obtained for the problem of steady-state turbulent flow of an incompressible liquid initiated in the gap between coaxial circular cylinders of radii R1 and R2 by the rotation of the internal cylinder of radius R1 relative to the common axis, with the other cylinder being fi xed (Taylor–Couette fl ow). The profi les of the angular and linear liquid velocities along the radius in the gap in the mode of a fully developed turbulence have been determined. The solution is compared with the well-known theoretical and experimental data at the radius ratio R1/R2 = 0.716 and Reynolds
numbers Re = 105, 106, and 2·106.
Keywords: near-wall turbulence, two-layer fl ow in a gap, boundary between fl ow subregions, full turbulence, profile of angular velocities.
PAGE 1440
Petrozavodsk State University, 33 Lenin Ave., Petrozavodsk, 185910, Republic of Karelia, Russia; email: babkin@ karelia.ru. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1440–1447, November–December, 2014. Original article submitted June 20, 2014.
ON THE PROBLEM OF THEORETICAL PRESSURE OF A RADIAL-FLOW PUMP UNIT
UDC 621.65.01
V. N. Pavlechko and S. K. Protasov
An analysis has been made of the velocity of motion of a medium in the wheel of a radial-fl ow pump unit under the action of a centrifugal force and overcoming the medium′s inertial force with its blades. Relations for the pressure produced by the radial-fl ow pump unit as a function of the angle of inclination of its blades have been derived. The
well-known Euler equation describing the dynamic pressure of the radial-fl ow pump unit has been supplemented to determine its static pressure. An analysis of the obtained results has shown that the pressure of the radial-fl ow pump unit is maximum at an angle of inclination of its blades of 110o and negative at 140o or larger angles.
Keywords: radial-fl ow pump unit, inertia of a medium, centrifugal force, velocity of a medium, theoretical pressure.
PAGE 1448
Belarusian State Technological University, 13 Sverdlov Str., Minsk, 220050, Belarus; email: . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1448–1454, November–December, 2014. Original article submitted July 14, 2014.
GENERAL PROBLEMS OF TRANSPORT THEORY
UDC 536.712;536.752
THERMODYNAMICS IN FRACTIONAL CALCULUS
R. P. Meilanov and R. A. Magomedov
A generalization of thermodynamics in the formalism of fractional-order derivatives is given. Results of the traditional thermodynamics of Carnot, Clausius, and Helmholtz are obtained in the particular case where the exponent of a fractional-order derivative is equal to unity. A one-parametric "fractal" equation of state is obtained with account
of the second virial coeffi cient. The application of the resulting equation of state in the case of the gas argon is considered.
PAGE 1455
Keywords: nonextensive thermodynamics, fractional-order derivative, fractal equation of state, specifi c heat at constant volume.
MASS TRANSFER OF CORROSION PRODUCTS IN THE NONISOTHERMAL SODIUM LOOP OF A FAST REACTOR
UDC 621.039.534.63
E. V. Varseev and V. V. Alekseev
The mass transfer of the products of corrosion of the steel surface of the sodium loop of a fast nuclear power reactor was investigated for the purpose of optimization of its parameters. The problem of deposition of the corrosion products on the surface of the heat-exchange unit of the indicated loop was considered. Experimental data on the
rate of accumulation of deposits in the channel of this unit and results of the dispersion analysis of the suspensions contained in the sodium coolant are presented.
Keyword: sodium coolant, corrosion, mass transfer, impurity.
PAGE 1466
A. I. Leipunskii Physical-Energy Institute, 1 Bondarenko Ave., Obninsk, 249033, Russia; email: , . Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1466–1471, November–December, 2014. Original article submitted May 20, 2014.
PROPAGATION OF THE RAYLEIGH WAVE IN AN INITIALLY STRESSED TRANSVERSELY ISOTROPIC DUAL-PHASE-LAG
MAGNETOTHERMOELASTIC HALF-SPACE
UDC 536.21
B. Singh,a S. Kumari,b and J. Singhb
The basic equations for the wave on the surface of an initially stressed transversely isotropic dual-phase-lag thermoelastic body subjected to the action of a magnetic fi eld were solved. Particular solutions were applied to the thermally insulated free surface of a half-space to obtain the frequency equation for the Rayleigh wave. This
equation was approximated for calculating the numerical values of the dimensionless velocity of the Rayleigh wave. The Rayleigh-wave velocity was represented graphically for the cases of coupled, Lord–Shulman, and dual-phaselag thermoelasticities. The infl uence of the dual-phase-lag and the initial stress of a body, the value of the magnetic
fi eld, and the frequency of the Rayleigh wave on the velocity of this wave were determined.
Keywords: dual-phase-lag thermoelasticity, Lord–Shulman theory, Rayleigh wave, frequency equation.
PAGE 1472
aDepartment of Mathematics, Post Graduate Government College, Sector-11, Chandigarh - 160 011, India, email: ; bDepartment of Mathematics, Maharishi Dayanand University, Rohtak — 124 001, Haryana, India. Published in Inzhenerno-Fizicheskii Zhurnal, Vol. 87, No. 6, pp. 1472–1479, November–December, 2014. Original article submitted July 18, 2013.