Connected equations of heat and mass transfer in a chemically reacting solid mixture with allowance for deformation and damage

Tomsk State University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 37, No. 3, pp. 97–108, May–June, 1996.     

Averaged expression for the bulk-density vector of the capillary force in a sintered powder mixture

An expression for the surface force in a medium with developed boundary surface that is convenient for practice is obtained by an additional space averaging of the known expression for the bulk density of this force in the form of surface-energy doubled density tensor divergence. Tomsk Branch of the Institute of Structural Macrokinetics, Tomsk 634021. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 4, pp. 165–167, July–August, 2000.     

Regularized numerical solution of the nonlinear,two-dimensional,inverse heat-conduction problem

Tomsk. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 1, pp. 106–112, January–February, 1995.     

Effect of rotation on the electrogasdynamic characteristics of flow in a cylindrical channel

Scientific Research Institute of Applied Mathematics and Mechanics, 634050 Tomsk. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 2, pp. 3–7, March–April, 1995     

Experimental study of variations in the thickness of a liquid film moving over the inner surface of a rotating cylinder

The behavior of a liquid layer moving in a mass-force field on the inner surface of a rotating vertical cylinder is studied experimentally. Free-surface profiles of the liquid moving under these conditions are constructed. An empirical dependence for the mean thickness of the film is obtained in criterial forms. The presence of a hydraulic jump in the lower part of the cylinder behind the entrance of the liquid onto the vertical surface is revealed. Tomsk, State Architectural-Building University, Tomsk 634003. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 6, pp. 65–71, November–December, 1998.     

Optimization of the earthreentry trajectory of a blunted body by the integral heat flux

The paper deals with optimization of the Earth reentry trajectory by the magnitude of the total convective heat flux at the stagnation point of a blunted body. The equations of a thin (hypersonic) viscous shock layer taking into account the nonequilibrium nature of chemical reactions and multicomponent diffusion are used as the initial mathematical model for heat flux calculations. The optimal solution is obtained by an effective robust method using the basic ideas of genetic algorithms. Institute of Applied Mathematics and Mechanics, Tomsk State University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 4, pp. 112–123, July–August, 2000.     

Experimental determination of the basic characteristics of heat and mass transfer upon thermoerosion fracture of materials

Using an original technique, heat and mass transfer in the interaction between a high-temperature heterogeneous jet with a high concentration of particles and the surface of structural materials was studied for the first time. The characteristics of heat and mass transfer were obtained under conditions of intense destruction of the materials under the action of a heterogeneous jet whose axis is perpendicular to the heating surface. Based on the results of experimental studies, some signs of high-temperature fracture of steel and cement grout under the action of a heterogeneous jet were revealed. Deceased. Tomsk State University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 2, pp. 138–143, March–April, 2000.     

Determination of the catalytic activity of materials by solving the equations of a nonequilibrium multicomponent boundary layer on a flat plate

A method is presented for determining the dependence of the probability of heterogeneous recombination γw from results of measurements of the heat flux Q_w to the surface of a catalytic sensor exposed to a pulsed supersonic flow of gas dissociated by an incident shock wave propagating in a shock tube. It is shown that the accuracy of the determination of γw depends not only on the accuracy of the measurements in the experiment, but also on the results of mathematical modeling of the flow of the dissociated gas over the surface of the body. Results from an analysis of an experiment are presented. Institute of Applied Mathematics and Mechanics at Tomsk University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 4, pp. 110–117, July–August, 1998.     

Analysis of fragmentation of deformation in Ni3Ge single crystals

The strain distribution on two faces ofNi ₃Ge single crystals compressed to a strain ε-14.16% at T=77.673K was studied by the grid method. It is shown that temperature has a significant effect on the strain distribution. Fragmentation of local strain due to shape change in specimens during active loading was established by the method of main components. Tomsk State Architecture-Construction Academy, Tomsk 634003. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 1, pp. 154–159, January–February, 1998.     

A study of heat-transfer processes in a supersonic flow around a spherically blunted cone with allowance for injection of a gas-cooler

The heat- and mass-transfer processes of a spherically blunted cone and a supersonic air flow are identified by the methods of solving direct and inverse problems with allowance for the heat flow along the contour and the injection of a gas-cooler. The ranges of applicability of the standard one-dimensional approaches and the method of a thin wall for recovering heat fluxes directed toward the body in flow are shown in the entire time period considered. State University of Tomsk, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 5, pp. 123–132, September–October, 1999.     

Generalization of the Clausius-Clapeyron equation in a coupled thermomechanical model

Several modifications of the Clausius-Clapeyron equation for deformable media, including solid-phase transformations which depend on the change of additional parameters, are proposed. A model of the medium with tensor concentrations of the components for which the unique Clausius-Clapeyron equation is also valid is proposed. The tensor analog of the transition heat is introduced, and an expression for the total transition heat related to the energies of chemical bonds in the crystal lattice is obtained. At least for slow processes, the fundamental possibility of determining the self transition heat in the experiment is shown analytically. Tomsk State University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 6, pp. 103–111, November–December, 1999.     

Bubbling of gas-particle mixtures

A formula for the particle passage coefficient, which describes the existing experimental data for Stokes numbersS<2, is obtained. Tomsk. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 113–121, July–August, 1998.     

Heat transfer in intumescent heat- and fire-insulating coatings

The physicochemical and thermophysical processes that jointly occur in intumescent heat- and fire-insulating coatings are studied numerically with the use of a model based on the hypothesis that the gaseous products of thermal expansion of an initial material are transparent. It is found that with the radiative mechanism of heat transfer in a layer of intumescent-coating coke taken into account, the temperature at the surface of a structure to be protected is almost equal to a temperature reached at this surface if a nonintumescent coating is used. Institute of Applied Mathematics and Mechanics, Tomsk State University, Tomsk 634050. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 3, pp. 143–149, May–June, 1999.     

Formation of thermal localized structures in a weld in pulse-arc welding by a nonmelting electrode

The technological regimes of welding that promote uniform distribution of the properties over the length of a welded joint are studied by numerically modeling the formation of a weld seam by a nonmelting electrode. Institute of Physics of Strength and Materials Science, Siberian Division, Russian Academy of Sciences, Tomsk 634021. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 6, pp. 172–177, November–December, 1998.     

Use of physical methods and electron microscopy in analyzing structural changes in Ni3Fe alloy

Results of studies of structural and mechanical properties ofNi ₃ Fe alloy are presented. The densities and types of dislocations in the alloy, the parameters of dislocation interaction, and the energy expended in deformation ofNi ₃ Fe specimens in various initial states are estimated. The strain hardening behavior of orderedNi ₃ Fe alloy is shown to be influenced by a number of external factors, such as deformation or γ-irradiation. Tomsk State Architectural University, Tomsk 634003. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 3, pp. 211–215, May–June, 1999.     

Study of the microstructure of a composite after dynamic fracture

Variations in the structure and phase composition of a composite of the hard-facing alloy type subjected to dynamic loading are studied by the methods of metallography and x-ray structural analysis at different scale levels. The dynamic action on the composite by a steel impactor led to the redistribution of the structural components with the formation of separate regions with different contents of a hardening agent, the formation of local sites with a structure different from the initial one, and the emergence of new phases. Institute of Strength Physics and Materials Technology, Siberian Division, Russian Academy of Sciences, Tomsk 634021. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 3, pp. 182–185, May–June, 1999.     

Effect of deformation and external load on the characteristics of martensite transformations and shape-memory effects in alloys based on titanium nickelide

The effect of plastic deformation and external load on the characteristics of shape-memory effects is studied for alloys based on titanium nickelide of nearly equiatomic composition. A nonmonotonic dependence of the characteristic temperatures of martensite transformations on the strain degree of deformation is obtained. This phenomenon is explained in relation to the stages of development of plastic deformation. Optimal loading and deformation conditions for obtaining maximum values of reversible deformation are determined. Russian Medical-Engineering Center, Tomsk 634034. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 2, pp. 175–181, March–April, 1998.     

Formation of periodic mesoband structures in the tension of polycrystals with long boundaries

A study is made of how the mechanism of plastic deformation of polycrystalline low-carbon steel is a ffected by large-scale interface in the form of long localized regions of remelted material extending in the transverse direction. It is shown theoretically and experimentally that oscillating stress mesoconcentrators develop in the neighborhood of such interfaces and that relaxation of these concentrators results in the formation of periodic mesoband structures in deformable polycrystals. Institute of the Physics of Strength and Materials Science, Siberian Division, Russian Academy of Sciences, Tomsk 634021. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 4, pp. 141–147, July–August, 1998.     

Description of creep within the framework of the field theory of defects

The creep laws are described within the framework of the field theory with the use of evolution equations for the density flux of uniformly distributed defects. For the case of uniaxial deformation under constant stress, it is shown that a certain critical stress that has the sense of creep stability limit exists and two deformation regimes can occur, depending on the magnitude of the external load. The unstable-creep rupture time is determined for the system in the case where the stresses are greater than the critical stress and the initial rate exceeds the unstable stationary rate. Institute of the Physics of Strength and Materials Science, Siberian Division, Russian Academy of Sciences, Tomsk 634821. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 3, pp. 177–183, May–June, 2000.