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One of the promising methods of geophysical research in operating wells is active thermometry. The method consists in creating an artificial temperature field in a well due to local heating of the metal casing. Observation of heat tags movement enables determining the fluid flow rate in the well and identifying the intervals of the behind casing flow. The article is devoted to the study of non-stationary thermal processes in a well during induction heating. The calculations were performed in the commercial simulator Ansys Fluent*. It was established that with an increase in the volumetric flow rate through the column from 5 to 50 m³/day for the modeling conditions, the maximum heating of the liquid (a change in the average mass cross-section temperature) is reduced by 85%, and the maximum heating of the column is reduced by 7%. The influence of natural convection on the formation of a temperature field in a liquid and a column has been studied. For the model with natural convection accounted, the column heats up significantly less than for the model without convection: the error in calculating the temperature changes due to neglect of natural convection can reach several hundred percent. During the process of induction heating for the casing, the effect of natural convection remains significant throughout the entire flow range of 5-50 m³/day.

The flow of liquid over the corrugated sheets of regular packings largely determines the processes of heat and mass transfer in distillation columns. An important role in the distribution of liquid over the structured packing sheets is played not only by the characteristics of packing surface microtexture, but also by the drip point location in the liquid distributor relative to the sheets in the structured packing plugs. It has been established that even a slight displacement of the drip point relative to the channels of a regular packing can lead to noticeable redistribution of liquid over the packing sheets. Knowledge of the detailed structure of the flow in the distillation column allows better understanding of the physical nature of the mechanisms that control the flow. It is shown experimentally that the negative impact of the uncertainty associated with the drip point position on the liquid distribution under a layer of structured packing can be reduced using liquid redistributors in the form of inclined plates with horizontal microtexture.

Three-dimensional numerical simulation of a transverse hydrogen jet blowing into a duct with a supersonic flow of air (warmed by a fire heater) has been carried out. The study is based on experimental data obtained at the ONERA-LAERTE facility. The RANS equations for the reacting gas were solved, closed by the SST model and various kinetic mechanisms of hydrogen combustion in air. The channel walls roughness was taken into account. The dependence of the flow characteristics on such physical factors as the shape of the fuel injector channel, the effective roughness height, and various methods of describing molecular diffusion has been studied. It has been established that the equivalent diameter of a grain of sand has a significant influence on the longitudinal pressure distribution in the duct. The influence of chemical kinetics on the flow structure in separation zones within the duct is demonstrated.

The study presents the results of simulation and experiment for motion of a supersonic two-phase jet passing through a round aperture in a mask. The mask is placed at different distances from the deposition substrate with performing the cold gas spraying. The calculations were performed using the fluid dynamics code ANSYS Fluent; flow visualization is achieved using the Schlieren method. Solution analysis and comparison of results were performed for example of aluminum powder spraying.

Phenol oxidation in a water-oxygen fluid in a tubular batch reactor with its uniform heating (1°C/min) to 600°C was studied. An increase in the amount of O₂ over the stoichiometric ratio by 25% leads to an increase in the degree of carbon burnout by the factor of 1.09. Replacing 10% of the stoichiometric amount of oxygen with nitrous oxide leads to the same increase in the degree of carbon burnout, primarily due to its afterburning at a temperature of ≥ 400°C. Replacement of some part of phenol with isopropanol leads to an increase in the degree of carbon burnout by 1.02 times. It was established for the first time that the heterogeneous mechanism of phenol oxidation in a water-oxygen fluid is the main one. However, the overstoichiometric amount of O₂, as well as the addition of N₂O and isopropanol, intensifies gas-phase combustion of carbon. A catalytic effect of a Pt-Rh/Pt thermocouple on the degree of phenol conversion in the presence of O₂ at temperatures above 135°C was found.

The enthalpy and heat capacity of solid and liquid Mg₂Ca intermetallic alloy were measured with the help of mixing by massive high-temperature isothermal drop calorimeter over the temperature range of 298.15-1177 K. The estimated errors in the data on enthalpy and heat capacity were 0.2% and 2%, respectively. The fusion enthalpy of the Mg₂Ca intermetallic alloy was determined to be 483 ± 3 J/g. The heat capacity of the Mg²Ca melt was shown to be constant in the range of 993.2-1177 K. A comparison of the obtained results with literature data has been carried out.

The presented paper considers a number of problems. The first of them concerns the analysis of experimental (ρ_l, ρ_g, T)-data for SF₆ at relative temperatures (1,5∙10^-8< τ < 0,3). The second task is related to the development of combined models (ρ_l(D, C, τ), ρ_g( D, C, τ), … ), that agree with a number of boundary conditions, including the requirements of the scale theory of critical phenomena. The third task is to calculate (D, C)-parameters included in the combined models; at this stage, a basic array of (ρ_l, ρ_g, T)-data is formed, including experimental results obtained in the laboratory of Prof. Funke (Germany), and (ρ_l, ρ_g, T)-data obtained by recalculating the results in the laboratory of Prof. Garrabos (France). The models for (ρ_l(D, C, τ) and ρ_g(D, C, τ) served as the basis for calculating some thermodynamic properties of SF₆ in the critical region.

Using the method of differential scanning calorimetry, the heat capacity of Mg-Ca alloys containing 10.50, 33.34, and 73.00 at. % Ca, being promising for various practical applications (biocompatible and biodegradable alloys, ultralight construction materials, anode materials, hydrogen absorbent materials, etc.) has been studied experimentally. New reliable experimental results on the specific heat capacity in the temperature range of 190-576.692 K of the solid state have been obtained. The estimated errors of the received data were 2-3 %. The reference tables for temperature dependences of specific heat capacity of Mg-Ca alloys have been compiled. It has been established that over a wide temperature range the heat capacity of solid magnesium-calcium alloys can be estimated with high accuracy using the Neumann-Kopp rule.

The paper describes an algorithm that using numerical methods allows calculating the relationship between the temperature of the spectral ratio and the actual temperature of a "non-gray" object, which takes into account not only the dependence of the spectral emissivity of the object on the wavelength, but also its temperature dependence, inherent in almost all real objects (materials). This algorithm is applicable to any pyrometers of spectral ratio: narrowband and broadband ones. Previously, both in domestic and foreign literature, there has been no solution to the specified problem which would simultaneously consider both dependences. The proposed solution is based on a well-known algorithm that allows calculating the relationship between the temperature of the spectral ratio and the actual temperature of a "non-gray" object, taking account only the dependence of the spectral emissivity of the object on the wavelength. The presented algorithm has been modified to consider its temperature dependence as well. An example of the implementation of the described algorithm is given.

The results of an experimental study of the thermal expansion of gallium garnets Gd₃Ga₅O₁₂, Gd_3.04Sc_1.8Ga_3.16O₁₂ and Ca₃Nb_1.5Ga_3.5O₁₂ in a wide temperature range (293.15 - 1473 K) are presented. A noticeable effect of niobium in the structure of gallium garnets on the coefficient of thermal expansion has been found. The temperature dependences of the volumetric properties have been obtained.