Home – Home – Jornals – 2011 number 4

The purpose of the article is to describe S.M. Solovyov's approaches to studying the early XVIII century epistolary sources for characterizing some aspects of the Age of Enlightenment. The special attention is paid to S.M. Solovyov's methods of interpretation of the epistolary sources regarding Peter the Great's activities in the sphere of book publishing, translating and binding at the beginning of the XVIII century. The author reveals the two methods used by S.M.Solovyov for the analysis of historical sources: 1) the source is viewed as a material object; 2) the source is viewed as an information object.

The paper deals with questions of the Orenburg province inhabitants' demand for books and periodicals at the end of the XIX - the beginning of the XX centuries which was in direct dependence to the readers' educational level, financial condition, their literary tastes as well as to the form of book distribution - by subscription, through the book trade, libraries. Having studied the information about the library stock of the Orenburg Cossack army the author concludes that for the most part it was composed of the hardcopy fiction lacking scientific and specialized literature; stresses the fact that the demand for periodicals was driven by advertising along with political situation in the country.

The article is devoted to the problems of con of the new electronic media and development of the existing ones. The author offers classification of the organization structure of the Russian television; describes peculiarities and contradictions in its formation. The main emphasis is placed on revealing the technologies and broadcasting specificity which allows characterizing the current state of the national television industry and foreseeing its further transformations.

The article considers the local tradition of worshipping the holy spring. In this connection the author describes the history of the church in Ryabovo; circumstances of the spring's showing up, pilgrimage to the spring; practice of vowing; cultic attributes.

Development of cosmonautics and preparation to the first manned space flights are briefly observed. Details of the development of the first Soviet intercontinental ballistic missile R-7, which served as a basis for creating Sputnik, Vostok, Voskhod, Molniya, and Soyuz launchers, are given. The contributions of the outstanding designers of space engineering, W. von Braun, S.P. Korolev, V.P. Glushko, and academician M.V. Keldysh, to the development of astronautics and first manned space missions are demonstrated. A list of test launches and manned flights of Vostok and Mercury spacecrafts and the basic characteristics of Vostok, Redstone, Atlas-D, Voskhod, and Soyuz launchers are presented.

An investigation of aerodynamic performance for micro air vehicle (MAV) wing is performed. It is shown, what is a reason of significant wing performance difference between tests, which were carried out in different wind tunnels. New method for estimation of wind tunnel condition influence on experimental results is suggested.

Results of numerical investigation of the effect of heat boundary layer thickness in front of a sudden expansion of a round tube on turbulent transfer in the zone of flow separation, attachment, and relaxation are presented. Before separation the flow was hydrodynamically stable, and the heat layer in front of expansion could change its thickness in maximally possible limits: from zero to a half of tube diameter. The Reynolds number varied from 6.7∙10³ to 1.33∙10⁵. It was found that the growth of heat layer thickness leads to reduction of heat transfer intensity in the separation area and moving away of the coordinate of maximal heat transfer from the place of tube expansion. Generalizing dependence for the maximum Nusselt number is given for variation of the heat layer thickness. Comparison with experimental data of [1] proved the main behavior tendencies of heat and mass transfer processes in separation flows behind a backward-facing step with different thermal prehistory.

The stability of the Couette - Poiseuille flow of a monodisperse mixture is considered. Sufficient stability conditions are derived. Results of the computation of the spectrum are presented. A considerable stabilization of the flow with particles admixture to small disturbances is observed. It is found that the regions of instability generation may have complex geometry. The influence of the main velocity profile and admixture parameters on the stability conditions is considered.

On the basis of the previously developed asymptotic theory of turbulent particle-laden flow with particle deposition in channels coupled with the transport model for the particle Reynolds stress, an asymptotic solution to the problem on the deposition of particles in the limit of high Reynolds numbers was obtained. The numerical calculations confirmed the presence, in the region of the transition from the diffusion-impaction regime of particle sedimentation to the inertia-moderated regime, bifurcation phenomenon of a solution found previously in earlier studies. Features of particle accumulation in the viscous sublayer are analyzed. On the basis of the numerical solution, correlations for particle deposition velocity were obtained. Boundary conditions of the wall-function type for particle concentration whose use allows widening the applicability limits of the equilibrium Eulerian models in terms of particle inertia are proposed.

Laboratory samples of small-sized energy converters based on thermo-electric method of heat conversion which source is diffusion microflame are presented in the work. Processes of combustion, energy conversion, and cooling in the proposed systems have been experimentally studied. Relatively high efficiency of the studied systems (energy-conversion 0.8 % at generated electric power of 130 mW) complying with the current world level for such devices is shown. The advantages of the proposed power generators are absence of forced-cooling system and catalysts, assemblage simplicity and usage of available materials and components. On the basis of investigation results, possible ways of further improvement of test samples have been determined with the view of energy conversion efficiency increase.

Filtration and separation properties were studied for filters made from open-porosity ceramics (sintered from authors-developed silicon dioxide nanopowder tarkosil". Key parameters were measured for samples of ceramics produced at different sintering temperatures: porosity, gas permeability coefficient, relative time of standard volume fill-up, gas mixture separation coefficient. The possibility of using the described ceramics for helium enrichment was demonstrated with examples of helium-nitrogen and helium-methane mixtures.

The modification of electrodiffusional method of the wall shear stress measurements is applied for registration of the Taylor bubble shear stress in an upward liquid flow. Time realization of shear is considered as a structure frozen into the flow, which moves together with a bubble. Experiments were carried out in laminar and transitional liquid flows. The wall shear stress in the liquid film around bubble averaged over the tube perimeter is presented for different flow Reynolds numbers and different lengths of the bubble.

The thermal-diffusive model was applied to the problem of flame propagation in a microchannel with controlled temperature distribution in the walls; this demonstrated the possibility of formation of oscillating or rotating spatial flame structures, which were described previously in experimental works on microcombustion. Two cases were considered: combustion in a rectangular channel and in the clearance between two disks with radial feeding of premixture. In both cases, the typical across size of the channel was lower than the critical diameter determined with respect to the ambient temperature. The gas flow was assigned and described by the Poiseuille-flow velocity profile. Formation of oscillating flame in a rectangular channel and rotating patterns in a radial channel was observed for a certain range of gas flow rate. At low flow rates beyond this range, repetitive ignition/extinction of flame took place; at high flow rate we observed a steady flame mode. Formation of these special flame structures is related to heat transfer between gas and hot walls of the channel, as well as to velocity maldistribution in the microchannel.

Dependence of spectral and energy characteristics of cesium plasma radiation on electric power P_{L has been found. It is shown that with PL growth metal vapor pressure increases; transformation of spectral structure of radiation manifested in disappearance of individual lines and increase of steady monotone takes place. Redistribution of average radiation power in individual spectral ranges is observed.}

The paper presents the investigation of plasma melting of the mixed bottom and fly incineration ash at various mixing ratios of the components. Chemical compound of the bottom and fly ash as well as the slag after its melting was analyzed by different methods, and the content of toxic components in them was determined. It is demonstrated that the direct disposal of the fly and bottom incineration ash may cause dioxin and heavy metal contamination of the environment. The influence of melted ash basicity on the resulting slag compound was studied. The mass balance of the melting process was defined. The tests were performed to determine the heavy-metals leaching from the ash and slag. It is also shown that the slag after plasma melting is dioxin-free and environmentally friendly.

The work presents the results of cycle computation for vapor compression pumps based on ozone-safe mixed refrigerants. Non-azeotropic binary refrugerants R32/R152а (30/70) and R32/R134а (30/70) were considered as working substances. Properties of non-azeotropic refrigerants were calculated according to the additivity method of thermodynamic functions and method of Lemmon and Jacobsen. Deviations in the values of thermophysical properties obtained with two methods have been determined. It is shown that at the use of non-azeotropic mixture R32/R152a (30/70), energy conversion ratio increases by 2.2−3.6 % compared with the results for R32/R134a (30/70) at temperature difference between the processes of boiling and condensation from 28 to 53 °С.

On April 13, 2011 Chief researcher of Lavrentiev Institute of Hydrodynamics SB RAS, Doctor of Physics and Mathematics, Professor Vladimir B. Kurzin  was  80 years of age.

The paper considers the optical contact-free method of droplet diameter sizing in the flow cross-section utilizing light interference on a droplet. Distribution of light scattered by a particle was analyzed for different configurations of the measurement system using the Mie theory and approximation of geometrical optics. Basic measurement errors and dynamic range were determined. Possibility of measurements with camera mounting at the angle of 90º to the plane of a laser sheet is shown; this simplifies setup calibration and evens characteristics over the image field. The procedure of measurement system calibration and a set of algorithms for data processing are suggested. The suggested approaches were applied for measurement of characteristics of the gas-droplet jet.

A two-dimensional physical and mathematical model of the motion and heat and mass exchange of a steam and gas mixture with liquid droplets of variable mass in sprayer sprinkling chambers at high moisture contents is formulated by using the concepts of interpenetrating continua with different velocities and temperatures. An analysis of this model is carried out.

Propagation of acoustic waves in nanodisperse powders and powder flow under the influence of acoustic vibrations have been investigated in the horizontal tube with the use of visualization and hot-wire anemometer methods.

The technique of lifetime measurement for metastable liquid and continuous depressurization technique were applied for study of kinetics of spontaneous cavitation in superheated liquid argon under impact of weak ultrasonic fields. It was demonstrated that acoustic cavitation may occur through the mechanism of homogeneous generation of vapor phase or through swinging of vapor bubbles generated by high-energy particles and/or other kinds of initiative factors. The thresholds of acoustic cavitation are described by the theory of homogeneous nucleation.

Results of experimental investigation of the bubbly gas-liquid flow in a vertical annular channel are presented. The average and pulsation shear stresses and distributions of local void fraction were measured by the electrochemical method on both channel walls. It is shown that with a rise of gas flow rate ratio the value of wall shear stress increases significantly, and this effect becomes higher at a decrease in superficial liquid velocity. A presence of the gas phase effects significantly shear stress on the inner wall. Relative intensity of shear stress pulsations increases similarly on both channel walls.

Laboratory samples of small-sized energy converters based on thermo-electric method of heat conversion which source is diffusion microflame are presented in the work. Processes of combustion, energy conversion, and cooling in the proposed systems have been experimentally studied. Relatively high efficiency of the studied systems (energy-conversion 0.8 % at generated electric power of 130 mW) complying with the current world level for such devices is shown. The advantages of the proposed power generators are absence of forced-cooling system and catalysts, assemblage simplicity and usage of available materials and components. On the basis of investigation results, possible ways of further improvement of test samples have been determined with the view of energy conversion efficiency increase.

The effect of different scratch techniques, mainly abrasive papers and scalpel blades used to form the junctions of temperature sensors, on the thermal-product value of these sensors, was examined. A dynamic calibration procedure of scratched sensors in a shock tube facility which allows easy evaluation of their thermal-product value is outlined. The thermal product of a particular sensor was found to be dependent on the flow Mach number, junction scratch technique, junction location, and also on the enthalpy conditions. It was shown that using different scratch techniques normally results in different thermal-product values of sensors. The experimental procedure used in the present study has yielded practical data on characteristics of scratched temperature sensors; these data can be used in accurate measurement of transient heat transfer under hypersonic flow conditions.

We have experimentally proved the applicability of hot-wire anemometer method to measure fluctuations at low pressures and gas flow rates when medium is no longer considered as continuous. Use of individual calibration at working conditions serves to apply standard technique for determination of sensitivity coefficients of hot-wire probes. Additional investigations are necessary to take into account influence of Knudsen number and, possibly, other parameters in heat transfer law presented as criterial dependence of Nusselt number on Reynolds number. Hot-wire measurement of mean velocity distribution and their fluctuations in the flow-through path of electric-discharge CO₂ laser have been performed. The level of velocity fluctuations in the vicinity of anode is high that is caused by the zone of interacting flows from the ventilators rotating in opposite directions forming in the symmetry plane. Placing of the damping screen between the ventilator and air gap allows decreasing fluctuations intensity to the acceptable level. It has been ascertained that the vortex shedding with high intensity of fluctuations which influence is noticeable in significant part of air gap is formed in the wake behind the streamlined cathode. However, pulsation level in the proper gap does not exceed permissible values.

Different turbulence models were studied in application to calculation of swirling flows. The differential models of turbulent viscosity considering streamline curvature and the method of detached eddy simulation were used. Weakly and strongly swirling flows were considered at the example of concentrated vortex in a tube, swirling flow in a diffuser, and vortex breakdown through an abrupt expansion. The RANS models with correction to flow swirling represented well the experimental data for the weakly swirling flows. In case of strongly swirling flows, it was more correct to use the method of detached eddy simulation.

The design of supersonic three-dimensional inlets using the V-shaped body forming a two-dimensional flow including an initial oblique shock wave and a subsequent isentropic compression wave is considered. Such a flow appears attractive for inlets design due to a possibility of obtaining high compression levels of external flow over the inlet ramp with small losses of the total pressure. Numerical computations of the flows around the designed configurations were carried out in design and off-design regimes using Euler code. The flow structure was identified, the aerodynamic characteristics of the inlets were determined. The investigation covers the range of supersonic speeds corresponding to the freestream Mach numbers М_∞ = 1.8−2.5.

In a subsonic wind tunnel, laminar boundary-layer separation at a backward-facing step on a flat plate modulated by stationary flow perturbations was examined. The stationary disturbances were introduced into the flow by controlled roughness elements spaced on the model surface close to the separation line. Through a comparison of obtained data with results gained in previous studies of other periodic roughness systems, some trends in the generation of stationary disturbances subject to transient growth in separation region were revealed.

A numerical analysis of turbulent regimes of the natural convection in a closed rectangular region with heat-conducting walls of finite thickness was carried out in the presence of a locally concentrated heat source under the conditions of the radiative-convective heat exchange with the ambient medium on one of the external boundaries. The mathematical model was constructed on the basis of the Reynolds equations in dimensionless variables stream function − vorticity vector − temperature. Special attention was paid to the investigation of the influence of the Grashof number 10^8<Gr<10^10, of the unsteadiness factor , and the thermal conductivity ratio a2,1=5.7*10^-4, 6.8*10^-5 on both the local and integral characteristics of the problem.

Structure, interdiffusion, and dynamic viscosity of eutectic Sn−Pb melt have been experimentally investigated in a wide temperature range. On the basis of the obtained data on the position and form of the first maximum of the structure factor in the framework of the hard sphere model, values of sphere packing index and sphere diameter have been determined for the melt at 470 and 570 K. Correlations resulting from the model of hard spheres served to calculate coefficients of dynamic viscosity and interdiffusion of liquid alloy. Besides, temperature dependence of dynamic viscosity has been calculated with the use of thermodynamic approximation of Kozlov ⎯ Romanov ⎯ Petrov. Calculated values of the properties have been compared with experimental data.

Results of experimental study for dependency of thermogradient coefficient on moisture in porous material have been presented. These experimental data were used for estimating the effect of hydrothermal conductivity on heat transfer.

The models were developed for thermal conductivity of a binding medium reinforced with tubes and with disperse-hardened hollow inclusions; the models have versions with/without consideration of relaxation times of materials making the phases of composition. For a limiting case, when tubes degenerate into solid fibers, we compared calculated values for efficient thermal conductivity coefficients for the case of single-direction and crisscross reinforced composites with corresponding experimental values. A satisfactory agreement between theory and experiment takes place.

Thermal conductivity of refrigerant 507А in gaseous state has been measured with a stationary method of coaxial cylinders in the temperatures range of 315 - 425 K and pressures 0.105 - 1.855 MPa. Estimated values of temperature, pressure, and thermal conductivity measurement errors are, respectively, ± 0.05 K, ± 3.75 kPa and ± 1.5 − 2.5 %. Approximation dependence for thermal conductivity in the whole studied temperature and pressure range has been obtained. Results have been compared with available literature data.

16 January, 2011  was the 80th anniversary of the Doctor of Technical Sciences, the Honored Worker of Russian Science, winner of the Award of the Council of Ministers of the USSR, Professor Anatoly Mikhailovich Kharitonov.

30 December, 2010  was the 75th anniversary of the Doctor of Technical Sciences, the Honored Worker of Russian Science, winner of the USSR State and of the Award of the Council of Ministers of the USSR, Professor Vladimir Kostantinovich Baev.

Within the theory of coupled clusters, it is proposed to use the orbital basis set of ethylene molecules in the π electron calculations of the polarizabilities and hyperpolarizabilities of conjugated systems. Test calculations show high accuracy of the method in comparison with the full configuration interaction method.

A comparative ab initio quantum chemical study of methanol interaction with potassium and rubidium hydroxides surrounded by DMSO molecules is performed. The reaction profiles of the formation of a nucleophilic particle in the direct interaction of methanol with an undissociated molecule of alkali metal hydroxide are considered. The levels of the description of the reacting system by different cluster continuum models are compared.

An ab initio quantum chemical study of the reaction profiles of the nucleophile particle formation in the interaction of methanol, methanthiol, and acetoxime with an undissociated molecule of alkali metal hydroxide is performed for the gas phase and also with the explicit inclusion of a dimethyl sulfoxide molecule into the calculation and with allowance made for solvation effects within the continuum model.

The vibration-rotation energy level spacings of homo- and heteronuclear rare gas dimers are calculated for some more common analytical intermolecular potential energy functions in
a unified way by employing the discrete variable representation (DVR) method.

In this paper, a first-principles study on the stability, electronic and magnetic properties of MRh₁₂ (M = Rh, Fe, Co and Ni) clusters is performed. By optimizing the geometrical structure, we find that MRh₁₂ clusters change from a perfect icosahedron to a distorted structure and have an obvious bond length contraction as compared with the corresponding bulk phase; FeRh₁₂, CoRh₁₂, and NiRh₁₂ clusters are more energetically stable than the RhRh₁₂ cluster. The effect of the impurity M on the density of states, valence band width, HOMO and LUMO for MRh₁₂ clusters is not significant, but when the central Rh atom is substituted with M, the magnetic moment of MRh₁₂ reduces dramatically. The Mulliken population analysis indicates that there are more charge transfers from other orbitals to Rh4d and M3d orbitals, and the spd hybrid effect in d orbitals of MRh₁₂ clusters is stronger than that in the RhRh₁₂ cluster. this situation means that the unpaired d electrons have more chance to be paired, and the magnetic moments of MRh₁₂ clusters can be reduced reasonably.