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Background. It is known that during the drop condensation of hydrocarbon vapors, the heat exchange between the vapor and the wall is 5-10 times greater than during film condensation. Therefore, the intensification of film condensation is the task of an efficient process of condensation of hydrocarbon vapors in oil refining. Purpose. To intensify the process of condensation of hydrocarbon vapors with a decrease in film condensation due to the vortex flow and increase the thermal efficiency of the process. Methodology. Technological parameters were measured, using instrumentation, processes of condensation of hydrocarbon vapors. Originality. For the first time, the degree of intensification of the condensation of hydrocarbon vapors in the experimental apparatus due to the circulating supply has been established. Findings. The circulating supply of steam in the apparatus leads to an increase in the heat transfer coefficient by 6.7%, and the amount of heat transferred by 7.8%, which leads to a decrease in the design dimensions, weight and working surface of the condensers. [ABSTRACT FROM AUTHOR]

Introduction. The ongoing research of the indoor temperature, regulated by automatically operating climate systems, remains relevant if focused on identification of dependencies which are sufficiently accurate with regard for the majority of essential factors and represented in the engineering format. The mission of the research is to identify a dependency between indoor temperature and time in case of irregular heat supply in the context of prorated heat flow regulation by indoor climate systems. The exponential nature of this dependency serves as the research hypothesis. Materials and methods. The author has employed and analyzed the principal equations connecting the most important constituents of a heat flow in a room that has automated climate systems in the context of discontinuous changes. The author has employed a computational model of a non-steady temperature environment of a ventilated room. The proposed model is based on the solution of a system of differential equations describing heat conductivity and transfer on indoor surfaces. The author has composed and analytically solved the general differential equation describing the indoor thermal balance with regard for the climate system’s feedback. Results. The author has developed an analytical expression describing the indoor space heating rate in case of prorated temperature regulation by the climate system and irregular heat supply. The analytical expression represents an exponential function of the square root of the time span starting from the moment of a heat supply spike. The author used a residential house in Moscow to analyze the nature of indoor temperature fluctuations with and without heat regulation. Conclusions. The author has proven that an indoor temperature rate is mainly driven by the relation between the transmission coefficient of a climate system and the thermal inertia of “massive” building envelopes in case of irregular thermal exposure. The author makes the point that a simplified analytical solution is proven true by the results of the analysis performed with the help of a numerical model. It’s been identified that the ultimate value of an indoor temperature increment is determined as the relation between the heat gain value and the parameter which is proportionate to the transfer coefficient. [ABSTRACT FROM AUTHOR]

Due to the scarcity and high cost of products from valuable species of fish, there is a need to produce their analogues, which in terms of nutritional value and taste would not be inferior to natural products. One of the methods for producing analogue of black caviar consists in the monodisperse crushing of a jet of solution prepared on the basis of the protein of chicken eggs with natural fish additives and black food coloring. Drops of the solution are sent to the granulation column, where they are heated to the temperature of the beginning of thermal coagulation of its protein component. The creation of isothermal conditions in the granulation column and the reduction of heat losses from its surface in order to increase the energy efficiency of the production are important problems encountered in the production of granulated products using this technology. To solve these problems, the temperature regime of the granulation column in the production of imitated monogranular food products has been studied using a numerical simulation method. By numerical solution of the system of equations of hydrodynamics and heat transfer for the flow of the forming liquid, the velocity and temperature distributions in the granulation column are obtained. The distance that a particle must pass in the granulation column to complete its gelling process has been found. The effect of thermal insulation of a column on heat loss from its surface is shown. [ABSTRACT FROM AUTHOR]

The work presents the results of development and manufacture of a unique research complex for investigation of fast processes of heat-mass transfer in consumable electrode arc welding. Advantages of the developed complex over the traditionally applied ones using film and video cameras with shadow principle of registration of heat and mass transfer characteristics are shown. Fast processes were studied with application of high-speed video recording with illumination of the arc gap by Cu-Br laser beam, improving visualization of the studied object — the process of melting and transfer of each drop of molten metal under the conditions of intensive light of the electric arc. The paper contains explanatory diagrams, control algorithms, video frames of a separate welding microcycle, examples of oscillogram recording and graphical representations of changes in their quantitative values. 13 Ref., 1 Tabl., 14 Fig. [ABSTRACT FROM AUTHOR]

The article compares calculation results in keeping with a mathematical model of industrial process of ethane pyrolysis carried out at the "Ethylene-Polyethylene" plant in Sumgait-city in terms of average permanent heat stress of the radiant coil with the results of the same process calculation but with the use of the proposed method of the zonal approach of fuel gas. When applying the latter, there is an essential fuel gas saving and higher yields of target products which ultimately provides the plant with considerable profit. Also, an expression has been suggested to determine optimum amount of fuel gas supplied to each zone. [ABSTRACT FROM AUTHOR]

The thermal effects are considered caused by the laser irradiation of external of solid surface with taking limited speed of heat expansion into account. Numeral calculations are presented on temperature distribution through the solid surface for different action band widths of laser radiation. An analytical expression has been got for the error evaluated due to taking into account the limited speed of heat expansion. The increase in the period of interference picture has been shown to result in localization of maximum values of temperature within the action zone of laser beams. This effect increases provided the limited speed of heat expansion is taken into account. [ABSTRACT FROM AUTHOR]