bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some features of the temperature-pressure dependence of the effective thermal conductivity of rocks
Authors: Emirov S N , Aliverdiev A A , Zarichnyak Yu P , Beybalaev V D , Aliev R M , Amirova A A 
Published: March 2021

Abstract
We have studied the behavior of the effective thermal conductivity of rocks (as natural heterogeneous materials) for the pressure range 0.1-400 MPa (initial region) and the temperature range 273-523 K. We propose a low-parametric empirical equation with great accuracy describing the effective thermal conductivity dependence, and discuss the physical meaning of its parameters.
Semi-industrial experimental studies of perspective technology for reducing harmful emissions produced by coal-fired thermal power plants
Authors: Boiko E A , Strashnikov A V , Shishmarev P V 
Published: March 2021

Abstract
The results of experimental studies of preliminary thermal processing of pulverized solid fuel under conditions of a semi-industrial installation for the preparation and combustion of coal with a productivity of up to 150 kg/h are presented. The studies were conducted over a wide range of pre-processing temperatures from 300 to 900 ° C, air excess from 0.2 to 0.9%, and the residence time of the carbon particles in the installation from 0.6 to 2.5 sec. The effect of preliminary thermal processing regimes on the reduction of nitrogen oxide emissions during the combustion of heat treatment products is shown experimentally. At a heat treatment temperature of 650-800 °C, emissions of nitrogen oxides are reduced by 2-3 times compared to burning of the initial fuel. An interpretation of the mechanism of the effect of preliminary thermal processing of coal on the reduction of nitrogen oxide emissions is proposed.
Application of a small deviation method in the study of the influence of external factors on gas turbine unit operation
Authors: Gubarev A Y , Kudinov A A , Eremin A V , Ziganshina S K 
Published: March 2021

Abstract
A correction system for energy characteristics of gas turbine units (GTU) Siemens SGT-100 and Siemens SGT-300 has been developed. It includes a set of analytical and graphical dependencies of technical and economic indicators on each of the environmental parameters (ambient air temperature ta
, relative air humidity ϕa, atmospheric pressure pat
, etc.) and other external factors at fixed values of other conditions. The dependencies are obtained by mathematical processing of experimental data under various combinations of external factors. In practice, obtaining experimental data at fixed values of external factors on the operating equipment of the power plant is difficult, since there is always a change in the environmental parameters and technological parameters of the equipment being tested. In the present paper, this problem was solved by applying a small deviation method when processing test results. The dependence between the output characteristics of the object under study and the parameters of external factors was assumed to be linear in a relatively small range of changes in the parameters under study. The article presents the study results of the influence of environmental parameters on the gas turbine units performance by a small deviation method on the example of gas turbines Siemens SGT-100 (4.7 MW) and Siemens SGT-300 (7.9 MW). The calculations were performed using the experimental inspection results of a gas turbine power plant, the main equipment of which includes gas turbines Siemens SGT-100 (4.7 MW) and Siemens SGT-300 (7.9 MW). The inspection was conducted in order to develop regulatory and technical documentation on fuel use, including energy characteristics of equipment, a correction system for deviations of external factors, and models for calculating nominal and normative specific consumption of equivalent fuel for the supply of electric energy.
Simulation of heat transfer in fire-tube and fire-tube-contact water heaters
Authors: Dolotovskii I V , Dolotovskaya N V 
Published: March 2021

Abstract
A mathematical model is proposed for calculating the constructive and operational characteristics of fire-tube and fire-tube-contact storage heaters used in the industrial, potable and firefighting water processing and storage units. The mathematical model includes equations for calculating heat balance, heat transfer, radiant heat transfer, and physical and chemical properties of substances. The heat transfer in fire tubes is calculated using a generalized process characteristic that is a function of structural and parametric indicators and heat engineering criteria. An example of application of the simulation software package for designing water heaters and conducting numerical experiments in order to draw up process flow diagrams accounting for variation of operational parameters and composition of fuel gas, is presented.
Nozzle design influence on the steam-driven ejector
Authors: Brezgin D V , Aronson K E 
Published: March 2021

Abstract
In the present paper, a series of numerical simulations of wet steam flows within ejectors distinguished by four primary nozzle contours have been carried out with the objective to evaluate the overall ejector performance. The studied primary nozzle contours are the following: a standard Laval nozzle (LAVAL); a nozzle that is designed in order to provide Constant Expansion Rate (CER); and two nozzles (MOC_SHORT, MOC_LONG) that are designed by employing axisymmetric Method of Characteristics. At first, the wet steam flow simulation throughout solely nozzles are carried out. Within the CFD simulations routines most valuable flow parameters are compared: expansion rates, boundary layer displacement and momentum thicknesses; entropy generation rate from various thermodynamic forces; thrust and liquid mass fraction across the nozzle exit plane. A comprehensive analysis of solely nozzles revealed that the CER nozzle contour is the most aerodynamically efficient design, which provides the minimum liquid mass fraction by the nozzle exit and possess the minimum entropy generation rate. The CFD results analysis of a full ejector domain revealed that an ejector with a MOC_SHORT primary nozzle contour provides the maximum performance in terms of secondary mass flow rate. At that, the secondary mass flow rate in MOC_SHORT nozzle contour case is almost 4% greater than for the CER nozzle design case.
Engineering method for calculating the operation modes of the heat supply station with the associated heat supply
Authors: Rafalskaya T A , Rudyak V Ya 
Published: March 2021

Abstract
The effective use of heat power in heat supply systems requires the development of new methods for central and local regulation of heat supply systems, the use of heat supply schemes with associated heat supply. The development of such technologies requires modeling and systematic calculations of variable modes of joint operation of local heat-consuming sys-tems. Currently used methods for calculating such operating modes of heat exchangers usually use constant parameters of heat exchangers. Such methods are not applicable in cases for large changes in temperatures and flow rates. Therefore, the calculation of variable modes of tied heat exchangers is usually performed by the method of successive approximations and is very time-consuming, which complicates the construction of a control system. In the present work, a fairly simple engineering technique is proposed for calculating the operating modes of heating stations of heat supply systems with associated heat supply. The basis of this technique is the use of previously derived analytical formulas that describe the change in the parameters of heat exchangers for various schemes of heating stations and temperature graphs of central regulation. The developed method allows the calculation of variable operating modes of the heat supply system without resorting to the method of successive approximations. The efficiency of the proposed methodology was tested on the operational data of the central heating station in the Kalinin district of Novosibirsk.
Performance analysis of control system tuning under inner disturbance influence by means of least square approximation to suboptimal algorithm and calculation using frequency optimality criteria
Authors: Kuzishchin V F , Merzlikina E I , Va Hoang Van 
Published: March 2021

Abstract
The performance of two known variants of automatic control system tuning has been analysed. The control systems contained PI and PID-regulators and disturbances influenced the process under consideration, the transfer function of the process was the second order with a transport delay typical for thermal processes. The methods used were the least square approximation to the suboptimal algorithm and the calculation method using indirect frequency optimality criteria. The PID-regulator used had a second order filter in the differentiator. The suboptimal algorithm had a second order filter with time constant T
c and correction coefficient k
τ for the regulator step response argument. Dependencies and approximation formulae for unambiguous definition of parameters T
c and k
τ using the process model parameters for the systems with PI and PID-regulators are obtained, some recommendations for determining approximation frequency range are given. When choosing these parameters the frequency oscillation index of the system is taken into account. When tuning for the indirect indexes approximating formulae determining the indirect indexes optimal values according to the process model parameters in the wide range are used. It is shown that for the system with a PID-algorithm when disturbances influence the process the tuning method using the indirect frequency indexes provides better performance of the control system. Moreover, it is more convenient for implementation in controllers, because it allows to make all the necessary calculations automatically during the one working cycle of the controller. For the system with a PI-algorithm both methods provide approximately equal performance of the control system.
All-mode Automatic Temperature Control System for Superheated Industrial Steam Boiler during Buffer Consumption of Gaseous Production Waste
Authors: Kuzishchin V F , Ismatkhodzhaev S K 
Published: March 2021

Abstract
The matter of the efficiency increase for an industrial steam boiler during the blast furnace gas buffer consumption is considered.. When transferring to the mode with the bigger part of the blast furnace gas (in relation to the natural gas) the superheated steam temperature significantly increases because of high blast furnace gas flows and flame movement. The ordinary range of injection change is not enough for the steam temperature stabilization behind the convective superheater second stage CSS2. There is a well-known solution of this problem for drum steam boiler E220-100 (220 t/h, 10 MPa, 540°C), for the solution a combined system is used, which, in addition to the traditional regulator of the steam temperature behind the CSS2 acting upon the injection, has a steam temperature regulator behind the CSS1 acting upon the flame position by means of turning burner air-control registers. Although the system performance was considered only for one steam flow load (100%). This paper shows dependencies for parameters of the dynamical model of the superheated steam temperature regulating channel on the load in the range of 64-100%. In order to provide the all-mode performance of the system it is offered to make automatic adjustment of the regulators parameters as the function of the steam flow according to the dependencies where the process dynamic changes are taken into consideration.
Reliability and efficiency of heat supply systems in the Leningrad region
Authors: Andreev Yu V , Grekov M A , Proskurin V M , Novikova O V 
Published: March 2021

Abstract
Currently, Russian heat supply system is at the stage of not just organizational, but also technological changes. Any decisions are based on determining priority criteria.
The goal of our research is to develop a set of organizational and technical solutions improving the efficiency of production and supply of heat to end consumers, taking into account the criterion that will be defined as the main one for a particular system. Current feasibility of the “generation” subsystem depends on the condition of its main generating equipment, the degree of its load, as well as the efficiency of the distribution of heat load between sources; “transportation” depends on the state of heat supply grids and the extent of their load; “consumption” depends on the state of thermal protection of buildings, losses of consumers, as well as the degree of automation of district heating substations.
The criteria may be:
1. Minimum time for the renewal of fixed assets: important in the conditions of disruption of the quality of heat supply. However, research did not confirm any significant violations[1]
2. Minimum variable costs: impact on the formation of tariffs for the population and the price for the industrial consumer;
3. Minimum grid transmission losses: for most systems, they are determined by regulations, not by actual measurements on heat supply grid sites. Not only the radius of effective heat supply and revised production technologies are important, but also the location of facilities and their capacity. However, confirmation of this version calls for implementation of a system for monitoring the state of heat supply grids, for example, based on optical fiber. This can lead to the development of distributed heat energy industry at the level of house heating substations;
4. Economic and budgetary efficiency, taking into account different project financing solutions.
Hydrogen energy and large scale hydrogen production with nuclear power plants based on high-temperature reactors
Authors: Petrunin V V , Marov I V , Kodochigov N G 
Published: March 2021

Abstract
At the present moment resource and ecological issues and challenges related to energy supply have become more acute. Key contradiction lies between constantly growing energy consumption and need for CO2 emission reduction. In the search of the solution hydrogen plays significant role as multi-purpose energy source and accumulator for transport, electric power, industry, distributed generation and public utility. It is expected that hydrogen energy development will benefit for the world’s energy system, environment and economy. Hydrogen may be used as pure fuel for transport and independent energy sources based on fuel elements. Global demand for hydrogen is expected to increase due to the growth of its consumption as a chemical agent in oil processing, petrochemical, chemical, metallurgic and other industries. In developed countries more than 80 % of hydrogen is derived from natural gas and petrochemicals. Large-scale hydrogen production is mainly accomplished by steam methane reforming. For natural gas saving and combustion products emission elimination steam methane reforming technology with heating from high-temperature gas cooled reactors (HTGR) is suggested. In 2018 hydrogen energy was declared as high priority area for scientific and technology development of Rosatom State Corporation. This area is integrated to the Comprehensive program project “Technology and scientific research development in nuclear energy of Russian Federation” and aims at design and demonstration of key technological solutions for nuclear hydrogen energy for large scale ecologic hydrogen production with heating from HTGR, hydrogen consumption infrastructure and integration of hydrogen energy into the economy. “Hydrogen energy” program implementation will diversify nuclear power non-electric applications.
Approaches to improving the efficiency and safety of the TPP gas economy based on internet of things technologies
Authors: Boldyrev I A , Sultanov M M , Kharitonov N V , Beokash A A , Menshikov P D 
Published: March 2021

Abstract
This paper describes the design features and characteristics of the “Fast-acting shut-off and control ball valve” proposed for possible replacement of the existing natural gas supply control systems of boilers and other gas-dispersing plants at the power plant. Application of FSCBV provides improvement of reliability and efficiency of gas economy of TPP due to design features, as well as application of technology of Industrial Internet of Things, which allows on the basis of statistical data to perform qualitative regulation, as well as prediction of possible failures.
Influence of indicators of quality of electric power on reliability of work of power transformer equipment of power plants and distribution networks
Authors: Strizhichenko A V , Zenina E G , Sultanov M M , Zhelyaskova O I 
Published: March 2021

Abstract
The lifespan of power transformers is largely determined by the state of their internal insulation, which is prone to aging during operation, now this problem is especially relevant for the operation of power transformers that have worked out a nominal life.
Direct control of internal insulation during the work is difficult due to the inaccessibility of windings for direct survey, and it is advisable to predict the residual resource for planning timely repairs. A refined model of the dependence of the speed of relative wear of the coil insulation not only on the load of the transformer, but also on the presence of asymmetry and higher harmonic components of the current is proposed
Mathematical model of the processes of restoration of power equipment in power systems by criterion of the index of technical condition
Authors: Kuryanov V N , Sultanov M M , Kuryanova E V , Skopova E M 
Published: March 2021

Abstract
The analysis of information about the joint use of reliability indicators and the technical condition index in assessing the state of the main electrical equipment on the example of power distribution schemes to the power system (PDSPS) of modern thermal power plants is given. The authors proposed to enter a new parameter – the index of technical condition for failure (ITCF). Technical assessment carried out by matching the actual values of the parameters of the technical state of the functional nodes with values set normative and technical documentation, as well as manufacturers, and then determine the index of the technical condition, the technical condition index to the failure of functional units and equipment for timely planning of repairs and prevent accidents. The paper presents the results of research of algorithms which allow us to form an improved approach to planning the repair program, taking into account the peculiarities of operation of the equipment.
The impact of the warm spells on reliability of the regional energy systems in Russia
Authors: Klimenko V V , Klimenko A V , Fedotova E V , Tereshin A G 
Published: March 2021

Abstract
The paper states the problem of the influence of extreme warm weather conditions on the Russian power system in a changing climate. The meteorological air temperature data of the warm seasons of 1945-2018 for the territory of Russia are analysed. The effects of summer warming of the Russian power systems are estimated using the relations between air temperatures and electric loads. Temperature load coefficients are calculated for four power systems of the European part of Russia. The effect on North-West, Siberian and Far East power systems was found to be negligible.
Influence of the axial compressor blade row defects on the industrial gas turbine performance
Authors: Blinov V L , Zubkov I S 
Published: March 2021

Abstract
This paper presents the compressor blade algorithm for predicting the defect influence on the characteristics of the stage, axial compressor or GTU as a whole. The developed model is based on the use of Bezier curves, with the control point coordinates calculated using the main geometric parameters of the airfoil, which provides highly precise geometry of both the airfoil and the blade as a whole. The paper shows some results of verification of the developed method and the selected numerical model parameters, as well as the analysis of the defect influence on the airfoil flow conditions in order to demonstrate the capabilities of the algorithm. The main results of the study were summarized and recommendations for further research were developed.
Technical and economical evaluation of a high-temperature air heater intended for integrated gasification combined cycle unit
Authors: Valtsev N V , Ryzhkov A F 
Published: March 2021

Abstract
In this paper the costs of creating a high-temperature air heater intended for the integrated gasification combined cycle unit developed by the authors are estimated and are compared with a steam boiler. The results can be used not only in the further development of the integrated gasification combined cycle plant under consideration, but also be interesting to specialists involved in the development of various high-temperature heat exchangers.
Experience and features of innovative training of specialists in the field of automation at the proving ground of power plant APCS
Authors: Tverskoy Yu S , Tselishchev E S , Golubev A V , Muravev I K , Nikonorov A N 
Published: March 2021

Abstract
Power units and power plants as automation and control objects are characterized by high dimension and redefinition, the presence of the uncertainty factor of most characteristics of a generally non-linear non-stationary system, as well as the action of random, as a rule, uncontrolled disturbances and a significant number of parameters inaccessible for direct measurement. The complexity of the technical system determines the appropriate level of requirements for the training of engineering and operational personnel in the field of modern automation and control systems, and at the same time requires the creation of adequate training tools and methodology by integrating fundamental engineering education and modern achievements in the field of information management technologies. The article summarizes the experience of 20 years of use and development of the educational and research complex «The proving ground of power plants APCS» for training specialists on the problems of modern technology of automation of energy facilities, advanced training of personnel of power plants, energy associations and engineering companies.
Mathematical support for the control system for nitrogen oxide emissions in boilers with furnaces with liquid slag removal
Authors: Parchevsky V M 
Published: March 2021

Abstract
When burning high-calorie low-volatile brands of coal in furnaces with liquid slag removal to achieve the standard concentration of nitrogen oxides in the outlet gases of the boiler, it is necessary to use two methods of reducing the concentration, for example, staged combustion and selective non-catalytic reduction. For optimal control of the two-stage process of successive concentration reduction, it is necessary to develop appropriate mathematical support that guarantees the maintenance of the standard concentration at any load of the boiler and minimizes the operating costs of reducing emissions. The scheme of mathematical support functioning is presented, which is an information processing system, the input of which is a signal from the steam load sensor of the boiler, and the output is a tasks for the regulators of the degree of stepwise combustion of fuel and urea supply, which ensure the optimal mode of operation of the emission control subsystem. The key issues of system development and operation are considered.