Volume 88, №5
EFFECTS OF THE TYPES OF INLET GAS DISTRIBUTION ON THE FORMATION OF A FLUIDIZED-BED STRUCTURE OPTIMUM FOR COMBUSTION OF FUELS WITH A HIGH VOLATILE YIELD
An experimental study has been made of the distributions of the coefficient of external heat exchange over the volume of the fluidized bed with different forms of inlet gas distribution. It has been shown that the grid giving a concave inlet profi le of the air velocity ensures a required homogeneity of the bed′s structure at a high level of heat exchange.
Author: V. A. Borodulya, Ya. S. Teplitskii, A. Zh. Greben′kov, D. S. Slizhuk, P. L. Is′emin, S. N. Kuz′min, and D. V. Klimov
Keywords: gas distribution, heat-exchange coeffi cient, regular thermal regime, heat-exchange sensor
FEATURES OF THE DECOMPOSITION OF GAS HYDRATES WITH THE FORMATION OF ICE IN A POROUS MEDIUM
We have investigated the features of the decomposition of gas hydrates into the gas and ice in the process of gas extraction from a porous medium saturated with the gas and the gas hydrate in the initial state. We have obtained selfsimilar solutions of this problem in an axisymmetric formulation describing the distributions of the main parameters in the stratum upon decomposition of the gas hydrate in an extended region. Critical diagrams of existence of the above solution have been constructed. It has been shown that in the case of a negative temperature of the stratum in the initial state (T0 < 273.15 K), the gas hydrate will always decompose into the gas and ice. At a positive initial temperature of the stratum (T0 > 273.15 K), the gas hydrate can decompose depending on the initial parameters of the system and the intensity of extraction of the gas with the formation of both water and ice.
Author: M. K. Khasanov, N. G. Musakaev, and I. K. Gimaltdinov
Keywords: gas hydrate decomposition, self-similar solution, porous medium
MATHEMATICAL SIMULATION OF THE TRANSPORT OF SALT IN THE CASE OF FILTRATION AND MOISTURE TRANSFER IN SATURATED–UNSATURATED SOILS IN A MOISTENING REGIME
Mathematical simulation of the process of the transport of salts by fi ltering a salt solution and by moisture transfer at the action of horizontal systematic drainage in a moistening regime has been made. Based on the developed computational algorithm, a numerical solution of the boundary-value problem of plane-vertical force-free stationary fi ltration of a salt solution to horizontal systematic drainage in the presence of a free surface of ground water in the region of a saturated–unsaturated soil has been obtained. The processes of fi ltration of a salt solution during the action of drainage in the region of complete saturation and moisture transfer and in the region of incomplete saturation are investigated with account for the transport of salts in corresponding subregions.
Author: A. P. Vlasyuk and T. P. Tsvetkova
Keywords: moistening regime, systematic drainage, fi ltration, salt transport, moisture transfer, complete and incomplete saturation, salt solutions
RELATION BETWEEN THE SUPERCOOLING AND CRYSTALLIZATION TEMPERATURES OF MOIST SOIL AND ITS STRENGTH IN THE FROZEN STATE
The laws of phase transformations of water in disperse materials are discussed using soil as the example. The dependence of the supercooling and crystallization temperatures of the soil moisture on the determining factors has been considered. The relation between the supercooling and crystallization temperatures of the freezing soil and the strength of the soil in the frozen state has been shown. A quantitative assessment of this strength has been made.
Author: A. A. Konovalov
Keywords: frozen soil, strength, supercooling, crystallization
INFLUENCE OF VIBROWAVE ACTION ON THE CHARACTER OF PRESSURE DISTRIBUTION IN A PERMEABILITY-INHOMOGENEOUS BED
Based on theoretical investigations, the infl uence of different kinds of generator-produced elastic waves on the character of change in the bottomhole pressure has been studied with account for the bed deformability. An analytical expression has been obtained allowing one to determine the dynamics and depth of elastic wave propagation in the bed with account for the bed collector deformation. It is shown that the degree of attenuation of elastic waves in deformable collectors increases considerably as against undeformable ones.
Author: É. M. Abbasov and N. A. Agaeva
Keywords: filtration, pressure, bed, vibrowave action, differential equation, Bessel function, period, fluid
INVESTIGATION OF THE STATE OF WATER IN ENERGY TREES IN THE PROCESS OF DRYING BY DIFFERENTIAL SCANNING CALORIMETRY
This paper presents the results of investigation of the state of water in young sprouts of energy trees (willow, poplar, and alder) in the process of drying to the limiting moisture content by differential scanning calorimetry. The content of freezing (free) and nonfreezing (bound) water in samples with various moisture contents has been determined. It has been shown that the specifi c content of bound water (referred to dry substance) Wb.w in the above trees in the process of their drying in the range from natural moisture to the limiting moisture content is not a constant quantity. In these trees in the state of natural moisture the Wb.w value exceeds their hygroscopicity limit, and in the process of dehydration the Wb.w value decreases. For instance, Wb.w varies from 0.419 to 0.254 g/g of dry substance for poplar, from 0.425 to 0.248 g/g of dry substance for willow, and from 0.354 g/g of dry substance for alder.
Author: V. A. Mykhailyk, Yu. F. Snezhkin, and N. V. Dmitrenko
PHYSICAL PROCESSES AND TECHNICAL MEANS FOR USING THE THERMAL ENERGY OF ALTERNATIVE SOURCES
The scheme of calculating the "pressure–concentration–temperature" diagrams with reference to a wide range of hydride-forming materials in determining the thermodynamic characteristics of sorption-type hydrogen heat-pump installations is presented. The schematic diagram and operating principle of a three-adsorber refrigerator with a complex activated carbon fi ber-alkali salts sorbent are described. This sorbent has a large cold holding capacity and a high rate of sorption. Experimental data attest to the high efficiency of the apparatus. The means of extraction of the low-temperature heat of soil and rocks for useful utilization are considered. The effi ciency of the Clausius–Rankine cycle exploited in the operation of electric and thermoelectric power stations with various organic working fl uids has been determined.
Author: L. L. Vasiliev, V. V. Solovei, D. Kh. Kharlampidi, A. A. Stachel,c T. Kujawa, V. A. Tarasova, A. S. Zhuravlev,a A. P. Tsitovich, and E. V. Kostenko
Keywords: heat pump, thermal transformer, hydrogen power engineering, renewable heat sources, geothermal energy, thermodynamic analysis, adsorption machines, absorption machines, sorption heat pipe, energy saving, Rankine organic cycle
DETERMINATION OF THE HEAT-TRANSFER CHARACTERISTICS OF THE VIBROROTATING BED OF A FINE MATERIA AS APPLIED TO THE QUENCHING PROCESSES OF STEEL PARTS
The quenching properties of MZM-26 industrial quenching oil have been compared with those of the vibrorotating bed of a fi ne material as applied to ShKh15 steel. The effi ciently of using a vibrorotating bed as a quenching medium for small steel parts has been substantiated by experiments.
Author: G. I. Zhuravskii, O. G. Martinov, A. A. Shipko, and T. N. Shtolik
Keywords: heat transfer, vibrorotating bed, fine material, quenching, steel part
ANALYSIS OF THE REGION OF VALIDITY OF EQUATIONS FOR CALCULATING HEAT EXCHANGERS OF THE TUBE-IN-TUBE TYPE
Based on the traditional model with direct fl ow and counterfl ow of heat transfer agents in a stationary regime, the operation of a heat exchanger of the tube-in-tube type is analyzed. Account is taken of the natural limitations for the model that are connected with the possibility of practical realization of the similarity numbers involved in the equations of the model, as well as with the conditions (assumptions) invoked in the derivation of the model. A comparison of the effi ciency of heat transfer in the noted regimes of heat transfer agent motions is made. For the purposes of this comparison, it is proposed to use an averaged value of the function that represents the ratio of effi ciencies with heat transfer agent direct fl ow and counterfl ow over the region of possible values of similarity numbers. The necessary calculations and illustrations are presented.
Author: A. I. Moshinskii
Keywords: heat transfer, heat exchanger, heat transfer agent, direct flow, counterflow
MULTILAYER, IMPLICIT, PARALLEL ALGORITHM FOR THE EQUATION OF HEAT CONDUCTION IN A PARALLELEPIPED
With the use of the method of computational experiment, a problem of heat distribution in a parallelepiped is investigated. It is shown that a three-dimensional problem can be solved on a PC
Author: S. D. Algazin
Keywords: heat condition equation, computational experiment
NONSTATIONARY AXISYMMETRIC TEMPERATURE FIELD IN A TWO-LAYER SLAB UNDER MIXED HEATING CONDITIONS
With the use of the Laguerre and Hankel integral transforms, the solution of a two-dimensional initial-boundary-value heat conduction problem for a two-layer slab under mixed boundary conditions is constructed: one of the surfaces is heated by a heat fl ux distributed axisymmetrically in a circle of radius R and is cooled by the Newton law outside this circle. The solution of the problem is reduced to a sequence of infi nite quasi-regular systems of algebraic equations. The results of numerical analysis of the temperature fi eld in the two-layer slab made from an aluminum alloy and ceramics are presented depending on the relative geometric properties of the components and cooling intensity.
Author: I. N. Turchin, I. Timar, and Yu. A. Kolodii
Keywords: nonstationary heat conduction, mixed boundary conditions, inhomogeneous body, Laguerre polynomials, paired integral equations
EVAPORATION OF WATER IN THE PROCESS OF MOVEMENT OF ITS LARGE MASSES THROUGH A HIGH-TEMPERATURE GAS MEDIUM
A numerical investigation of the heat transfer in large monolithic water masses and water masses with different spaces fi lled with water vapor and gases, moving through high-temperature gases at temperatures higher than 1000 K under the conditions of phase transformations, has been performed. The completeness of evaporation of the water from a water mass moving in a high-temperature gas medium was numerically estimated with account for the degree of inhomogeneity of the water mass.
Author: A. O. Zhdanova, G. V. Kuznetsov, and P. A. Strizhak
Keywords: heat of vapor formation, heat transfer, evaporation of water, water mass, fl ame zone, combustion, high-temperature gases
PHYSICAL PRINCIPLES OF OPERATION OF A TWO-STAGE LIGHT GAS MAGNETOPLASMA LAUNCHER FOR HIGH-VACUUM BALLISTIC TESTS
The results of experimental and theoretical investigations of the operation and a two-stage light gas magnetoplasma launcher are presented. An optical method for measuring the velocity of small bodies (2–10 mm) has been developed and used in testing a combined gas discharger for micro- and macroparticle acceleration. The experimental results are in good agreement with the mathematical model of the two-stage light gas gun in the approximation of constancy of the accelerating pressure behind the striker
Author: P. P. Khramtsov, O. G. Penyazkov, V. A. Vasetskii, V. M. Grishchenko, A. I. Makhnach, and I. A. Shikh
Keywords: plasma, erosion plasma, accelerator, laser ballistic chronometer
TEMPERATURE CORRECTION IN PROBE MEASUREMENTS
This work is devoted to experimental investigations of a decaying plasma using Langmuir probes. The gas pressure, the discharge current, and the moment of afterglow were selected to obtain probe characteristics in collisionless, intermediate, and drifting regimes of motion of charged particles. The manner in which the shape of the volt–ampere characteristics changes on passage from the collisionless motion to diffusion motion has been shown. A detailed analysis has been made of the source of errors arising when orbital-motion formulas or the logarithmic-operation method are applied to processing of the probe curves. It has been shown that neglect of collisions of charged particles in the probe layer leads to an ion-density value overstated more than three times, an electron-temperature value overstated two times, and an ion temperature overstated three to nine times. A model of interaction of charged particles in the probe layer has been proposed for correction of the procedure of determining temperature. Such an approach makes it possible to determine the space-charge layer in the probe, and also the value of the self-consistent fi eld. The use of the developed procedures gives good agreement between experimental and theoretical results
Author: S. A. Gutsev
Keywords: low-pressure plasma, afterglow plasma, Langmuir probes, orbital motion, volt–ampere characteristic, particle energy distribution function, electron temperature, space-charge layer
SEPARATION OF AN ASSIGNED POLARIZATION COMPONENT OF ELECTROMAGNETIC RADIATION IN ITS REFLECTION FROM AN ANTIREFLECTION ABSORBING SUBSTRATE
We have found conditions ensuring separation of one of the two polarization components of electromagnetic radiation incident at an angle on a plane antirefl ection absorbing substrate
Author: S. R. Kasimova and É. R. Kasimov
Keywords: electromagnetic waves, polarization components, absorbing substrate
GENERALIZATION OF EXPERIMENTAL DATA ON HEAT TRANSFER AND HYDRAULIC RESISTANCE OF CHANNELS WITH SPHERICAL PROTRUSIONS
Experimental investigations of hydraulic resistance and heat transfer in channels with intensifi ers in the form of systems of spherical protrusions have been generalized in a wide range of working and design parameters. A unifi ed approach to the correlation of experimental data of various investigators with account for the differences in the geometry of heat transfer surfaces has been worked out. Unifi ed universal dependences for the coeffi cients of hydraulic resistance and heat transfer in channels with spherical protrusions are obtained.
Author: I. A. Popov, A. V. Shchelchkov, and M. Z. Yarkaev
Keywords: intensifi cation, spherical protrusions, hydraulic resistance, heat transfer coeffi cient
NUMERICAL INVESTIGATION OF THE VENTILATION PROCESSES IN A CLOSED SPACE IN THE PRESENCE OF PEOPLE AND HEAT SOURCES
The fl ow of a viscous gas in a model section of a closed ventilated space, in which people and objects radiating heat are found, was investigated with the use of numerical-simulation methods. A numerical algorithm developed on the basis of the program package VP2/3 was used for simulation of a nonisothermal turbulent fl ow of a viscous gas in the indicated space. In the process of simulation of this nonstationary gas fl ow, the Reynolds equations closed with the use of the differential k–ω model of turbulence in the SST modifi cation of Menter were solved. The effi ciency of the mathematical model and the numerical algorithm used in the calculations was verifi ed by comparison of their results with experimental data.
Author: S. A. Isaev, P. A. Baranov, A. E. Usachov, and D. A. Malyshkin
Keywords: ventilation, closed space, turbulence, MSST model, VP2/3 package
ON THE DYNAMIC STABILITY OF A CONE IN A SUPERSONIC FLOW WITH A STRONG COUNTER GAS BLOW FROM THE SURFACE OF ITS BLUNT PART
The infl uence of a strong gas blow from the surface of the spherical blunt part of a cone to meet the incident supersonic fl ow on the stability of the directed movement of the cone was investigated.
Author: F. M. Pakhomov
Keywords: supersonic flow, angle of attack, counter blow of gas, nose, dynamic stability
USE OF WENO SCHEMES FOR SIMULATION OF THE REFLECTED SHOCK WAVE–BOUNDARY LAYER INTERACTION
Numerical simulation of the shock wave–laminar boundary layer interaction is carried out on the basis of the model problem at different Reynolds numbers. The use of WENO schemes of high order of accuracy is demonstrated. The calculated shock-wave structure of the fl ow is compared with the data available in the literature and with the data obtained from TVD schemes. Criteria of accuracy of numerical calculations that are related to the position of shock-wave structures, and also the time of solution of the problem with various difference schemes, are discussed. Recommendations on practical use of difference schemes of high order of accuracy are given.
Author: P. V. Bulat and K. N. Volkova,
Keywords: shock wave, boundary layer, numerical simulation, WENO schemes
SUPERSONIC FLOWS IN CHANNELS AND JETS WHEN APPLIED TO THE PROBLEMS OF DESIGNING AERODYNAMIC WINDOWS OF GAS LASERS
Consideration is given to issues associated with the development of aids for mathematical modeling of steadystate supersonic perfect compressible gas flows in aerodynamic windows of gas lasers. A comparison is made of fl ow patterns in supersonic jets, which appear when a uniform velocity distribution and a velocity distribution corresponding to the free vortex are realized on the nozzle section. Aids for designing channels are developed on the basis of solution of a sequence of primal problems. The calculation results show the high effi ciency of the developed software as applied to solution of problems associated with the contouring of channels and nozzles and with the control over supersonic jet fl ows.
Author: K. N. Volkov, V. N. Emel′yanov, and A. V. Pustovalov
Keywords: aerodynamic window, supersonic flow, nozzle, jet, marching method.
ON TRANSFORMATIONS OF THE VELOCITY HODOGRAPH IN CERTAIN PROBLEMS OF FLUID MECHANICS
Consideration is given to the fl ow-velocity hodograph representing a circular hexagon in polar grids with two cuts, which is used in the theory of jets and cavitation, gliding theory, gas dynamics, the theory of groundwater motion, and fi ltration theory. It has been shown that in recording the parameter characterizing the ratio of the radii of circles, which are the opposite polygon sides with cuts, the confi guration and relative position of the latter substantially change not so much with the properties of the functions on whose basis particular solutions of the corresponding Fuchsian-type equation are constructed, as with the ranges of conformal-mapping constants involved in the expressions for mapping functions. It has been established that to different ranges of variation in these constants there can correspond cuts varying in confi guration and relative position. This is a manifestation of the transformation of liquid and gas fi ltration fl ows under the infl uence of different physical factors.
Author: É. N. Bereslavskii
Keywords: Fuchsian differential equations, conformal mapping, region of the velocity hodograph, circular and rectilinear cuts, elliptic Jacobian functions, theta functions
INFLUENCE OF THE EXTERNAL FORCE ON THE VORTEX–SOURCE COMBINATION CRISIS
This paper considers the force stagnation of a supersonic vortex–source combination fl owing out into a vacuum, leading to a decrease in the radial Mach number to unity and stationary fl ow choking. The similarity parameters infl uencing the crisis are analyzed. It has been shown that the ″force″ crisis (choking) is also possible for the vortexsink combination fl owing out of a submerged space. The formulation of the thermal crisis problem is generalized to the case of a given external force per unit mass and in a unit volume. Comparison has been made between certain characteristics of the crisis due to the applied external force in the absence of power supply/removal and the characteristics of the crisis due to the heat input in the absence of external force. The investigation has been carried out from the viewpoint of the perfect gas model.
Author: A. N. Kucherov
Keywords: vortex–source combination, vortex-sink combination, radial external force, fl ow rate, circulation, radial Mach number, flow choking, crisis.
NUMERICAL INVESTIGATION OF THE DURATION OF THE EFFECT EXERTED BY INITIAL REGIMES ON THE PROCESS OF LIQUID MOTION IN A PIPELINE
By using numerical methods, the duration of the effect exerted by initial regimes on the running state of a nonstationary process of liquid motion in a linear part of a pipeline has been investigated depending on the values of various parameters of this process. The process is described by a system of two hyperbolic-type partial differential equations.
Author: E. R. Ashrafova
Keywords: hyperbolic equation, dissipation factor, pipeline
ABOUT THE DIVERGENT FORM OF EQUATIONS FOR A ONE-VELOCITY MULTICOMPONENT MIXTURE
The divergent form of the equations of a generalized equilibrium model of a multicomponent mixture, in which the interfraction-interaction forces are taken into account, is discussed. The modifi ed Godunov method developed for integration of model equations is described. A number of one-dimensional and two-dimensional problems were calculated with the use of this method.
Author: V. S. Surov and I. V. Berezanskii
Keywords: one-velocity multicomponent mixture, hyperbolic system of equations, divergent form, Godunov method, linearized Riemann solver
FREE CONVECTION FLOW PAST A VERTICAL CONE WITH A CHEMICAL REACTION IN THE PRESENCE OF TRANSVERSE MAGNETIC FIELD
Natural convective heat and mass transfer over an isothermal vertical cone due to the simultaneous action of buoyancy, chemical reaction, and transverse magnetic fi eld is studied. The governing boundary-layer equations are transformed into a dimensionless form, and then the resulting unsteady nonlinear coupled partial differential equations are solved by using an effi cient, more accurate, and unconditionally stable implicit fi nite difference scheme of the Crank–Nicolson type. A parametric study is performed to illustrate the effect of the buoyancy ratio parameter, Prandtl number, Schmidt number, chemical reaction parameter, and the magnetic fi eld parameter on the velocity, temperature, and concentration profi les. The local and average characteristics: shear stresses, heat transfer coeffi cients, and mass transfer coeffi cients, are obtained numerically. The numerical results reveal that the velocity decreases in the case of a destructive reaction, whereas it increases for a generative reaction.
Author: G. Palani and A. R. Ragavan
Keywords: one, chemical reaction, magnetohydrodynamics, implicit fi nite difference, Nusselt number
THERMOELASTIC WAVES WITH THERMAL DIFFUSION IN AN ISOTROPIC MICROPOLAR PLATE
The generalized theory of thermodiffusion is applied to study the propagation of plane harmonic waves in an infi nitely long isotropic micropolar plate. The present analysis also includes both the thermal and mass diffusive relaxation times, as well as the coupling of the thermal diffusion with microrotation of the material. To determine the effect of the presence of thermal as well as mass diffusion on the phase velocity of the wave propagation, two potential functions are used, and more general dispersive relations are obtained for symmetric and antisymmetric modes. The results for the cases of thermoelasticity, micropolar thermoelasticity, and thermodiffusive elasticity are derived. The changes in the phase velocity, attenuation coeffi cient, and the specifi c loss factor with the wave number are shown graphically
Author: S. Shaw and B. Mukhopadhyay
Keywords: thermodiffusion, mass concentration, micropolar plate, relaxation time, phase velocity
NUMERICAL INVESTIGATION OF FLOW IN A CENTRIFUGAL COMPRESSOR
With the use of the domestic software suite of computational hydrodynamics FlowVision based on application of the method of control volumes, numerical simulation of air composition and delivery by a centrifugal compressor employed for supercharging a piston engine has been carried out. The head-fl ow characteristics of the compressor, as well as the 3D fi elds of fl ow velocity and pressure distributions in the elements of the compressor fl ow passage, including the interblade channels of the impeller, have been obtained for various regimes. In the regimes of diminished air fl ow rate, surging phenomena are identifi ed, characterized by a return fl ow. The application of the technique of numerical experiment will make it possible from here on to carry out design optimization of the compressor fl ow passage profi le and thus to improve its basic characteristics — the degree of pressure increase, compressed air fl ow rate, and the effi ciency — as well as to reduce the costs of the development and production of compressors.
Author: Yu. A. Grishin and V. N. Bakulin
Keywords: computational hydrodynamics, method of control volumes, FlowVision suite, centrifugal compressor, head-fl ow branches, velocity and pressure fields
NUMERICAL ALGORITHM FOR INVESTIGATING LARGE ELASTO-PLASTIC DEFORMATIONS
A method of investigating the stressed-strained state of elasto-plastic bodies subjected to large deformations is presented.
Author: R. L. Davydov and L. U. Sultanov
Keywords: large deformations, nonlinear elasticity, plasticity
INVESTIGATIONS INTO THE INTERCASSETTE COOLANT INTERACTION IN THE WWER-1000 REACTOR CORE WITH DIFFERENT MODIFICATIONS OF FUEL ASSEMBLIES
The authors give the results of experiments investigations into the intercassette interaction of the coolant in the WWER-reactor mixed core consisting of TVSA–T and TVSA–12 PLUS. The investigations were carried out on an aerodynamic stand by the method of gas tracer diffusion. An analysis of the spatial distribution of projections of the absolute fl ow velocity and of the propagation of the tracer concentrations enabled the authors to particularize the pattern of coolant fl ow past the spacer and mixing grids of the fuel assemblies.
Author: S. M. Dmitriev, A. V. Varentsov, A. A. Dobrov, D. V. Doronkov, A. N. Pronin, V. D. Sorokin, and A. E. Khrobostov
Keywords: core, fuel assembly, spacer and mixing grids, intercassette interaction, hydrodynamics of the coolant
MODELING OF COOLANT FLOW IN THE FUEL ASSEMBLY OF THE REACTOR OF A FLOATING NUCLEAR POWER PLANT USING THE LOGOS CFD PROGRAM
Results of computer modeling of coolant fl ow in the fuel assembly of the reactor of a fl oating nuclear power plant using the LOGOS CFD programs have been given. The possibility of using the obtained results to improve models built into the engineering programs of thermohydraulic calculation of nuclear-reactor cores has been considered.
Author: S. M. Dmitriev, A. A. Dobrov, M. A. Legchanov, and A. E. Khrobostov
Keywords: core, reactor facility, fuel assembly, heat and mass transfer, computational hydrodynamics.
RECONSTRUCTION OF THE VORTEX-JET STRUCTURE OF THE SEPARATION TURBULENT FLOW IN A SPHERICAL DIMPLE ON THE WALL OF A NARROW CHANNEL WITH INCREASE IN THE DEPTH OF THE DIMPLE AND INTENSIFICATION OF THE SECONDARY FLOW IN IT
On the basis of an analysis of the reconstruction of the vortex-jet structure of the completely developed turbulent fl ow of an incompressible fl uid in a spherical dimple on the wall of a narrow plane-parallel channel with increase in the depth of the dimple, a map of regimes of separation fl ow around such a dimple at a Reynolds number of 40,000 has been developed with special emphasis on the intensifi cation of the multivortex fl ow formed in the indicated dimple in the case where a symmetric fl ow in it is changed to the axisymmetric one.
Author: S. A. Isaev, A. I. Leont′ev, A. V. Shchelchkov, and M. E. Gul′tsova
Keywords: spherical dimple, narrow plane-parallel channel, swirling flow, turbulence.