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Experiments were carried out to measure the velocity field in a hanging droplet, blown by external air at a constant velocity. The maximum velocity on the surface of a droplet depends on velocity of the external air and on the radius of a droplet. Comparison of convection for different liquids was performed. It has been shown that the velocities inside a droplet significantly differ for different single-component liquids and for aqueous solutions and depend on the concentration of components. [ABSTRACT FROM AUTHOR]

The results of experimental studies on forced convection of a fluid inside a droplet blown by an external gas are carried out. The convection velocity in a droplet depends on the gas velocity and a droplet diameter. The experimental data are compared with numerical solutions. When a water droplet is blown by air, an underestimation of the velocity in droplet is observed, in comparison with the calculation, by about 35–40 times. It is assumed that a strong discrepancy between experiment and calculation is associated with the accumulation of impurities (contaminants) on the free surface of a droplet. In the absence of a free surface (liquid-gas), the calculation satisfactorily describes the experimental data. The case of a drop of one liquid in a flow other liquid is considered. Convection for different liquids is compared. [ABSTRACT FROM AUTHOR]

The heat exchange in conditions of pebble bed with spherical fuel were studied in wide range of main operational parameter variation. The inlet velocity of the flow was varied in range 0.5-5 m/s, the pressure – in range 3-9 MPa, inlet gas temperature – 573-1073 K, heat generation rate – 1-20 MW/m3. The helium was used as the coolant. The surface temperatures were determined by thermodynamic calculations and simulation via Ansys, The correction factor to the heat transfer coefficient value was introduced to match the maximal fuel surface temperature obtained by simulation and engineering calculations. The main factors affecting the maximal surface temperature of spherical fuel in conditions of pebble bed reactor were determined. [ABSTRACT FROM AUTHOR]

The paper includes the study of mathematical modeling of the process of obtaining gaseous tungsten hexafluoride based on the reaction between tungsten powder and fluorine in a chemical reactor, the working zone of which is an annular channel, is presented. Simulation of the fluorination process is carried out on the basis of solving the equations of momentum transfer, heat and mass transfer in a binary mixture, taking into account the heterogeneous reaction taking place at the bottom of the channel between the layer of tungsten powder and the gas flow. As a result of the numerical solution of the problem, the distributions of the fields of the velocity vector, concentration and temperature, as well as the characteristic of the completeness of the use of fluorine, are found. [ABSTRACT FROM AUTHOR]

The temperature distribution along the thermosyphon height was experimentally established under the conditions of supplying the heat flow to the lower cover, which is typical of the operation of electronic equipment. It is shown that the drop condensation occurs on the condenser upper cover at heat flux of up to 1.8 kW/m2 on the lower cover of the thermosyphon evaporator. However, when the heat flux is in the range from 1.8 to 5.1 kW/m2, the drop-film condensation occurs. [ABSTRACT FROM AUTHOR]

This article deals with the paradigmatic relations established by lexical units of the lexical-semantic field "Smart Energy System" in modern English, which is considered to be an essential aspect of the structural and systemic analysis. The paper presents an overview of different views within the field and discusses the term "paradigmatic relations" with regard to the issue of definition, representative types, their origin and categorical signs of mutual correlation. The conclusion is that the paradigmatic relations of lexical units of the lexical-semantic field "Smart Energy System" in the modern English system are characterized by their own hyper-hyponym nature, where synonyms and antonyms form the most stable paradigmatic rows. [ABSTRACT FROM AUTHOR]

The article deals with the study results of the corpus (500 blogs) of English transhumanist blogs with the tag "Anti-aging" (here and after ATB) and subject areas of their texts, which are presented in the form of articles and comments. Within the framework of the corpus under study, the subject areas of the "transhumanism" sphere are represented by the following units: "Health" "Longevity", "Wellness", "Fitness", "Beauty", "Fat loss", "Products". Each of these areas is characterized by certain lexical, grammatical and syntactic features, supported by examples from the ATB texts. [ABSTRACT FROM AUTHOR]

The paper deals with hendiadys as a linguistic phenomenon considering the issues of its historical background and distinguishing features as part of binomials. Indeed, binomials have frequently been employed in various genres and by various authors throughout the history of English. Thus, the aim of this paper is both to retrace the history of hendiadys as part of binomials from Old English to Present-Day English including the periods of Middle and Early Modern English and to review their significant peculiarities in the English language. [ABSTRACT FROM AUTHOR]

The ignition and combustion characteristics of the brewery's spent grain in conditions of excess air pressure were studied by means of constant pressure Vielle bomb experimental setup. The spent grain of the Tomsk brewery was used. Experiments were performed in air atmosphere at different pressure varied in range 1-5 bar. The ignition delay time and burnout time was determined for pelletized samples via high-frequency video imaging. Increasing pressure resulted into increasing of the ignition delay time values while the burnout and total combustion time values were decreased. Simulation of heat transfer in experimental chamber revealed that temperature field changed insignificantly and indicated that the major contribution was made by change in features of chemical reactions. [ABSTRACT FROM AUTHOR]

The paper includes schemes for preparation and recycling of coal and coal-containing wastes using hot circulating particles in boilers with a circulating fluidized bed, the processing of coals into special types of coke in a thermo-oxidative coking unit, the preparation of fuel in a conveyor with heating jackets, the briquetting of coal mass and its use as special coke or smokeless fuel. [ABSTRACT FROM AUTHOR]

The article discusses the theoretical and practical foundations of the study of the possibility of replacing heating oil with gaseous fuel released during special heat treatment of coal, as well as the introduction of this method of heating boiler units at coal-fired thermal power stations. The results of an experimental study of three types of coals in order to obtain the necessary gaseous fuel are presented. [ABSTRACT FROM AUTHOR]

Accounting for energy consumption for heating, ventilation and hot water supply creates economic prerequisites for the introduction of regulation of heat consumption in buildings and structures. To reduce heat consumption in buildings, without deteriorating the conditions for a comfortable state of the microclimate in the premises, it is necessary to carry out a number of measures to save energy and increase energy efficiency, one of which is the use of systems for automatic weather-dependent regulation of the heat transfer agent supply. The article provides an analysis of the efficiency of the automatic regulation systems of heat points in the budgetary sphere. [ABSTRACT FROM AUTHOR]

This paper compares the operating parameters of the simplest power converters, which are obtained using analytical calculations, laboratory research and modern programming environments. Software application allows for more accurate time graphing of transient processes in electrical circuits. [ABSTRACT FROM AUTHOR]

The issue of using a condensation heat exchanger operating on the principle of indirect evaporative cooling in systems of gas energy equipment is considered. Various designs of heat exchangers using heat of indirect evaporative cooling and their use in systems of gas energy equipment are proposed. [ABSTRACT FROM AUTHOR]

They are protected from short circuits between pipe buses in a short network of ore-thermal production by means of electrical insulation, the destruction of which leads to the occurrence of an arc between them, and then to the complete destruction of an expensive bus package. In this regard, the current protection of the short circuit of the ore-thermal production from short circuits on one magnetic current transformer has been developed. The presented protection is simple in design, capable of diagnosing short circuits in a short network and timely disconnecting the transformer from the network when a short circuit appears between the pipes in the short network. [ABSTRACT FROM AUTHOR]

Resource conservation issues are relevant in the energy sector, for example, the development of relay protection devices without the use of metal-intensive current transformers. For the construction of relay protection devices, it is proposed to use reed switches. However, it was determined that the parameters of the reed switches are not constant and can vary with the magnitude of the acting magnetic flux. Additional research is needed to improve relay protection devices using reed switches. [ABSTRACT FROM AUTHOR]

The process of thermal conversion of reactor graphite modified with Cu(CH3COO)2 activation additive (5 wt.%) was researched. Application of copper acetate on the reactor graphite samples was carried out by incipient wetness impregnation method with preliminary dissolution of Cu(CH3COO)2 in water-alcohol mixture with volume ratio of C2H5OH/H2O equal to 50/50. Activating properties of the additive under conditions of composition change of blown gas (air/argon) were studied by thermogravimetric analysis at the heating rate of 10 °C/min in the temperature range of 25-1200 °С at atmospheric pressure. It was found that the change in the composition of blown gas affects activity of the additive, which is expressed in the displacement of characteristic temperatures of the graphite thermal conversion process. [ABSTRACT FROM AUTHOR]

Oxidation and pyrolysis processes of brewing industry waste have been researched. Elemental composition and technical characteristics of the investigated sample were determined with the help of elemental analyzer and standard methods. Thermal transformation of the sample was performed by the method of thermogravimetric analysis at the heating rate of 10 °C/min up to the maximum temperature of 700 °C. Air and argon with flow rate of 150 ml/min were used as blown gas. Thermal analysis data (DTG curves) were used to determine the process stages which correspond to mono- or bimodal release of volatile compounds and oxidation of the resulting carbon residue (for oxidation mode). The characteristic temperatures of the beginning and end of oxidation (Ti=242 °C and Tf=612 °C) and pyrolysis (Td=255 °C and Tf=460 °C) as well as the reaction time and rate were determined. The qualitative analysis of gas-phase products of thermal conversion of the sample was performed by the mass spectrometry method. The activation energy values of the processes under consideration were calculated by the Coats-Redfern method and their values were about 19 kJ/mol. [ABSTRACT FROM AUTHOR]

The issues of organization of operation of heat generation systems as modernization objects considering modern requirements of their prospective development as an integrated combination of traditional heat generation system with RES components and technologies are shown in the article. The main directions of development of generation systems with RES components in assessment of ecological and economic approaches of modernization are formulated. Technological capabilities of RES-components for implementation of energy-efficient modernization and low-carbon emissions projects and creation of integrated electric power systems of thermal energy are shown. [ABSTRACT FROM AUTHOR]

This paper presents the results of the method developed by the authors for effective torque monitoring of synchronous electric motor, which does not require additional measuring devices and provides the required quality of measurements indirectly. Simulation model and programs for investigation of static and dynamic indices of indirect torque monitoring of implicitly synchronous electric motor were developed. The simulation experiment results are shown. The recommendations on application of the method of indirect torque monitoring are given. [ABSTRACT FROM AUTHOR]

This article offers methods for attaching and configuring Magneto sensitive elements (ME) without using current transformers, used for building relay protection, for example, building filters of symmetrical components at any location of the phases of current pipelines. [ABSTRACT FROM AUTHOR]

It is noted that in relay protection resource savings can be achieved by replacing current transformers with ferromagnetic cores with miniature current sensors, such as inductance coils, reed switches, etc. It is emphasized that special designs are required for their mounting near the busbars. Models of two such designs for mounting reed switches are proposed. The first differs from the known ones by the presence of a single stepper motor connected to a microcontroller, which makes it possible to remotely move the reed switch in the horizontal plane, and the second – two electric motors, which allows you to move the reed switches in the vertical plane. At the same time, the microcontroller is located in the relay compartment of the cell of the complete switchgear, which ensures the safety of service personnel. The method of regulating the position of reed switches in space using the proposed designs is described. [ABSTRACT FROM AUTHOR]

It is noted that the replacement of current transformers with some other, less metal-intensive and bulky, current sensors is an urgent task in the electric power industry. The advantages and disadvantages of some of these sensors are briefly considered. The advantages of reed switches over other current sensors are given and their operating principle is described. It is stated that on the basis of obtaining information about the current in the phase of an electrical installation from reed switches, a number of short-circuit protections have already been developed. The full resistance measuring body is considered in detail and its operation in the short-circuit and load mode is described. A directional resistance relay is proposed with a simple circuit for test diagnostics of a fault, consisting of a button, a control winding worn on the starting reed switch, two intermediate relays and a current control block in the specified winding. The method of selecting the parameters of actuation of the measuring body is presented and its operation in various modes is described. [ABSTRACT FROM AUTHOR]

The article discusses the principles of electrical circuits formation and includes analysis, which showed that two-way feed ring and trunk networks are the most promising and efficient in technical and economic terms. It has also been found that, currently, in a closed configuration network in the normal operating mode of a network with two power sources, one of the lines must be disconnected. This is due to the impossibility to selectively trip a damaged line, in particular, with single phase-to-earth fault (SEF). It describes that the SEF is the main type of electrical damage in 6-10 kV cable networks. [ABSTRACT FROM AUTHOR]

A method has been developed for diagnostics of the short-circuited rotor damage of asynchronous motor by external magnetic field. The information sign is a change in amplitude of harmonic components of this field measured with the help of point induction converters. A method for determining the sliding of an asynchronous motor by an external magnetic field is proposed. [ABSTRACT FROM AUTHOR]

Experimental studies of heat transfer in the "emitter – air – heat supply object" system have been carried out in order to register the horizontal surface temperatures depending on the distance to the infrared heater. According to the results of the experiments, it was found that the temperature of the equipment surface areas influenced by the heater is significantly uneven. The temperature difference can reach 20 degrees, and an increase in the height of the object by 2 times increases its surface temperature by 67%. It has been established the need of considering the possible overheating of equipment located in zones heated by infrared heaters when developing systems for ensuring the regulatory thermal regime in large industrial premises. [ABSTRACT FROM AUTHOR]

The article presents the results of research on the energy efficiency of the main equipment of the electrolysis production in a metallurgical plant. The objects of research were the main and bypass busbars of the electrolysis shop. The temperatures of busbars, voltages on electrolyzers, voltage drop at busbar junctions, the operational state of busbars, the composition and content of impurities in busbars were experimentally determined, and the parameters of busbar electrical conductivity and voltage losses were determined analytically. The main purpose of the study was to substantiate the feasibility of replacing busbars and recommendations for improving the energy efficiency indicator during their operation. [ABSTRACT FROM AUTHOR]

In this paper, the calculation of a combined cycle including a gas and steam circuits with two nuclear reactors is done. The first circuit of the thermal scheme is the gas cycle with a very high temperature reactor (VHTR) and the second circuit of the combined scheme is the steam cycle with the pressurized water reactor (VVER). VHTR which is one circuit reactor and uses Helium as a coolant and working fluid and VVER is a two circuit reactor which uses water as a coolant and steam as working fluid. The scheme was limited by the parameters of the two reactors and aimed at reaching the highest thermal efficiency of the power of the two reactors. The calculations showed the effect of changing the parameters of one reactor side to the other reactor side, on the total efficiency and power output. These parameters are the thermal power of VHTR core and the compression ratio of the gas turbine and their effect on the steam turbine power output, the steam cycle efficiency, the gas turbine power output and the gas cycle efficiency. Finally, the results showed high thermal efficiency of the scheme comparing to the two the thermal efficiencies of each single cycle. [ABSTRACT FROM AUTHOR]

We studied experimentally the effect of nanosecond pulsed laser processing of silicon-carbide ceramic surface on tribological properties of its near-surface layer. Tribological properties were estimated using the friction coefficient, which was determined on the ball-on-disk tribometer at the reciprocating motion under normal stress conditions when the load changed from 1 to 5 N. We found that nanosecond pulsed laser processing of silicon-carbide ceramic surface changes the texture of its near surface layer. This texture was characterized by a lower friction coefficient, which was 20% less compared to that of unprocessed surface. A significant decrease in friction on the surfaces of silicon carbide ceramics increases the efficiency of devices that use surfaces of silicon carbide ceramics. [ABSTRACT FROM AUTHOR]

Experimental studies for the evaporation of a sessile and hanging droplet of aqueous salt solution were carried out. When spray cooling a hot wall, it is required to simulate both the heat transfer of falling droplets and the heat transfer of sessile droplets on the wall. It is shown that the ratio of the maximum velocity to the average convection velocity is approximately 2.5-3 both for a hanging and a sessile droplet of salt solution. [ABSTRACT FROM AUTHOR]

Experiments on the evaporation of a hanging drop of water in a stream of air were carried out. The velocity for a hanging drop is about 30-40% higher than for a sessile droplet of water. It is shown that the ratio of the maximum convection velocity to the average convection velocity is approximately equal to three, for both a hanging and a sessile droplet of water. [ABSTRACT FROM AUTHOR]