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The approximate kinetic analysis was carried out for the problem of strong condensation based on conservation equations for molecular fluxes of mass, momentum, and energy within the Knudsen layer. The closing relation was the condition for conservation of condensation flux between the Knudsen layer boundary and the mixing layer. Approximate analytical solution of the problem was obtained in the form of pressure ratio vs. temperature ratio (Mach number as a parameter). The analytical solution demonstrates a good agreement with available simulation data.

Method of measuring the lifetime of the superheated liquid was used to determine temperatures of the limit superheating of the solution of oxygen-nitrogen-helium. The method of calculating the properties of this solution (temperature of limit superheating, saturated vapor pressure, and density) based on the data on the properties of solutions of oxygen-helium and nitrogen-helium was proposed. The surface tension of the solution of oxygen-nitrogen-helium was determined in a special experiment.

Investigation results on the arc plasmatorch for water-steam heating are presented. The construction arrangement of steam plasma generator with copper electrodes of the stepped geometry was firstly implemented. The energy characteristics of plasmatorch and erosion of electrodes reflect the features of their behavior at arc glow in the plasma-forming environment of steam. The results of numerical study of the thermal state of the composite copper-steel electrodes had a significant influence on optimization of anode water-cooling aimed at improvement of its operation life.

The equations were obtained for description of heat transfer in composite bodies with reinforcement with a set of smooth tubes with pumping of incompressible liquid coolant. The appropriate boundary-value problem of heat transfer was formulated with the following qualitative analysis. The steady temperature fields in cylindrical shells with spiral-shaped tube reinforcement (with liquid coolant flow) were simulated. The influence on the temperature fields from the side of reinforcement geometry parameters, flow direction and velocity, tubes cross sections was studied. It was found that these characteristics allow significant variation of temperature field in its gradients within the composite item: this open ways for effective control of temperature fields.

The article presents the results of an experimental study of the influence of powder nanomodifiers of refractory compounds on the mechanical properties, macro– and microstructure of heat-resistant alloys ZhS–6K and Inconel 718. It is shown that the introduction of nanomodifiers into the melt leads to the refinement of the alloy structure: the average grain size decreases 1.5–2 times, and their morphology becomes similar to equiaxial at significant reduction of the particle size in the carbide phase. The service life of ZhS–6K alloy under cyclic loading at 600 ºC increases 2.7 times, and at 975 ºC by 40 %, and relative elongation increases more than twice. The mechanical properties of Inconel 718 significantly increase: long-term strength at 650 ºС increases 1.5–2 times, and the number of cycles before the collapse at 482 ºС grows more than three times. It has been found out that addition of nanomodifiers to the melt, in alloys, forms clusters of particles of refractory compounds at borders and joints of the formed grain structure that may help slowing down the processes of recrystallization (prevents the increase in the size of the contacting grains by their associations) and stabilizes the strength properties of the alloys at higher temperatures.

The prominent scientist in the field of heat and power engineering, Honorary Professor of the Ural Federal University, Honored Scientist of the RSFSR Albert P. Baskakov passed away on January 21, 2015.

Obtained in underground excavation in Tashtagol Mine, Kemerovo Region, and in dislocation area in karst in Iskitim marble quarry, Novosibirsk Region, the experimental data give evidence of the change in the velocity of seismic wave packets depending on energy of mechanical impulse inputs when elastic waves propagate in the system of mineral body-fault zone-mineral body. It is shown in the article that the resulting dependences between first arrivals of seismic wave packets and energy of impact (source) conform with the kinematic relationship typical for pendulum waves in high-stress structured geomedia.

Based on the approach using the method of splicing asymptotic expansions with the retention of only the dominant term of the asymptotics, in plane deformation conditions, the authors model stress state of rock mass with the horizontal daylight surface and a horizontal bed with a long slot-like excavation. The rock mass is assumed elastic, uniform and isotropic, whereas the bed undergoes elastic and, then, elastoplastic deformation. In the latter case, the length of the face zone of plastic deformation is supposed to exceed the bed thickness and to be less than the length of the excavation.

The authors analyze seismo-thermal effect (STE) that is the internal heating of ground under the action of external vibration and impulse mechanical oscillation within a frequency range from units to hundred of hertz. It is found the STE has some general features such as “fatigue,” relaxation and freezing. The article reports long-term temperature monitoring under a platform of a periodically actuated vibration source. The empirical relationship for the level of STE and the depth below the vibration source platform is offered, and the interconnection of the STE level and the vibration power is shown.

The authors describe calculation of rock failure around breakage headings in coal mines based on two-dimensional problem of the theory of creep with high deformation. The case of non-ring induced disintegration of rocks and the influence of mine-geological parameters are illustrated.