|HEAT-AND-POWER ENGINEERING FUNDAMENTALS|
E.K. Vachagina, A.I. Kadyirov
HEAT transfer in laminar flow of THE FOUR-MODe PhAN-TIEN-TANNER fluid IN A circular tube (Transactions of Academenergo. 2019. N 4. pp. 7-20). doi: 10.34129/2070-4755-2019-57-4-7-20.
e-mail: email@example.com, firstname.lastname@example.org
Federal Research Center «Kazan Scientific Center of Russian Academy of Sciences»
Keywords: Phan-Tien-Tanner fluid, Weisenberg number, Nusselt number, viscoelastic fluid, flow, heat exchange
In this paper, we present a mathematical model of heat transfer in laminar flow of four-mode linear Phan-Tien-Tanner fluid in circular tube. The parametric method is developed to solve the statement problem. The velocity distribution is analyzed under various values of the Weissenberg number. The method of expansion of the desired functions in power series is applied to obtain a solution to the energy transfer equation. The distribution of Nusselt numbers along the pipe length for various values of the Weissenberg numbers is obtained.
A.G. Laptev*, M.I. Farakhov**, E.A. Lapteva*
PROBLEMS AND SOLUTIONS OF LARGE-SCALE TRANSITION IN CHEMICAL TECHNOLOGY (Transactions of Academenergo. 2019. N 4. pp. 21-35). doi: 10.34129/2070-4755-2019-57-4-21-35.
*Kazan state energy University, **OOO ITC “Inzhekhim»
Keywords: mass transfer, scale transition, flow structure, numerical modeling.
The actual problem of scaling of industrial devices of chemical technology, which is to reduce the efficiency of the processes by increasing the size of the devices, especially in two-phase media. The main causes of large-scale effects associated with increased hydrodynamic inhomogeneities in the apparatus without the use of special design solutions are presented. The basic approaches and methods for solving the scale transition based on flow structure models, hydrodynamic modeling, coupled physical and mathematical modeling, and numerical methods are given. The advantages and disadvantages of these approaches and methods are considered.
D.A. Telyashov, G.I. Pavlov, P.V. Nakoryakov, E.A. Sukhovaya
EXPERIMENTAL STUDY OF THE EFFECTIVENESS OF THE REDUCTION OF SHOCK WAVES OF LOW INTENSITY FLUID LAYER OF CONSTANT THICKNESS (Transactions of Academenergo. 2019. N 4. pp. 36-50).
e-mail: email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org
Research Center for Power Engineering Problems of the Russian Academy of Sciences
Keywords: noise attenuation, fluidized bed, shock waves of low intensity, aerodynamic valve, pulsating combustion chamber
The aim of this work is to study the efficiency of low-intensity shock wave noise attenuation by a fluidized bed of constant thickness. In this paper, the main method of research is experimental. The paper presents the results of experimental studies to reduce the intensity of weak shock waves in the fluidized bed. The studies were carried out on a test bench that allows simulating gas-dynamic processes in the aerodynamic valve of the pulsating combustion chamber. On the basis of the obtained results, practical recommendations for creating a noise muffler of the aerodynamic valve of the pulsating combustion chamber are formulated. Due to the complexity of modeling the fluidized bed in the path of the noise silencer, this experimental work allows a deeper understanding of the physical processes in the silencer with fluidized bed.
|POWER AND MECHANICAL ENGINEERING|
M.M. Yakovlev, R.R. Yarullin
IMITATION MODELING METHODS OF OPERATION LOADING CONDITIONS FOR TURBOMACHINERY ELEMENTS (Transactions of Academenergo. 2019. N 4. pp. 51-64). doi: 10.34129/2070-4755-2019-57-4-51-64.
e-mail: email@example.com, firstname.lastname@example.org
Research Center for Power Engineering Problems of the Russian Academy of Sciences
Key words: imitation model, gas turbine engine, steam turbine engine, compressor disk, turbine disk, rotor blades, fatigue life, lifetime, stress-strain state
This paper provides an overview of methods of imitation modeling of operation loading conditions for structural elements. The theoretical, numerical and experimental foundations of the principles of imitation modeling are considered. A review of the well-known papers in this area was carried out. The advantages of imitation modeling with respect to the traditional methods of testing specimens and full-size structures are demonstrated.
LIFE PREDICTION METHODOLOGY BASED ON DAMAGE ACCUMULATION MODELS FOR THE CREEP-FATIGUE INTERACTION (Transactions of Academenergo. 2019. N 4. pp. 65-75). doi: 10.34129/2070-4755-2019-57-4-65-75.
Institute of Power Engineering and Advanced Technologies, FRC Kazan Scientific Center, Russian Academy of Sciences
Keywords: creep-fatigue interaction, damage accumulation, life prediction
The numerical results of predicting the residual life based on damage accumulation models for the ВТ3-1 titanium alloy are present. All mechanical properties were obtained at temperature 370С. Life prediction was based on the Kachanov – Rabotnov damage model for creep and the Duyi-Zhenlin model for fatigue. The contribution of each type of loading to the generalized damage parameter was calculated according to the law proposed by Skelton. Damage accumulation laws were integrated into ANSYS software. Cyclic loading with a trapezoidal form cycle was simulated. The integrated model of damage accumulation under creep-fatigue interaction allows obtaining fatigue life of structural elements. The model is recommended to be used for cases when the scalar damage parameter is justified.
|POWER GENERATION STATIONS|
R.Z. Aminov, V.E. Yurin, M.A. Murtazov
RELIABILITY ASSESSMENT OF THE RESERVE SYSTEM FOR NPP OWN NEEDS BASED ON THE SMALL POWER ADDITIONAL STEAM TURBINE (Transactions of Academenergo. 2019. N 4. pp. 76-87). doi: 10.34129/2070-4755-2019-57-4-76-87.
e-mail: email@example.com, firstname.lastname@example.org
Saratov Scientific Center of the Russian Academy of Sciences
Keywords: nuclear power plant, multifunctional additional steam turbine, backup of auxiliary needs of nuclear power plants, reliability assessment, blackout, core damage.
Modern safety systems have a number of disadvantages, such as high cost and single purpose use, leading to the additional cost of maintenance. The authors have developed an alternative option for cooling down VVER-type reactors when they completely de-energize by supplying own needs consumers through the beneficial use of residual heat energy from the core to generate steam, which serves as working heat for an additional low-power steam turbine. A reliability preliminary assessment of the emergency power supply of NPPs auxiliary needs by means of traditional emergency power supply systems with diesel generators and using an additional steam turbine installation for periods of running-in and normal operation is carried out. In the calculation, data, published based on a large investigation conducted in the USA on the percentage of non-launch of diesel generators, were used. The evaluation results demonstrate a significant discrepancy between the dependences of the failure rate of the study systems for different percentages of failure to start diesel generators. A three-channel emergency power supply system with three diesel generators, which was laid down earlier at the design stage of nuclear power plants, does not fully satisfy the IAEA safety standards. The installation of an additional constantly working multi-function steam turbine at a nuclear power plant is one of the most effective ways of backing up NPP own needs in emergency situations with blackouts, which allows to meet modern requirements and safety standards.
V.A. Khrustalev, M.V. Garievsky
ON THE EFFICIENCY OF NPP USING EQUIPMENT OF THE START-UP BOILER (Transactions of Academenergo. 2019. N 4. pp. 88-97). doi: 10.34129/2070-4755-2019-57-4-88-97.
e-mail: email@example.com, firstname.lastname@example.org
Saratov Center of Science of Russian Academy of Sciences
Keywords: nuclear power plant, start-up boiler, power complex, maneuverability, variable loads
The purpose of the work is to determine the conditions for the effective use of a start-up boiler house at the NPP site to obtain additional power at peak hours. The method of estimation of fuel efficiency on the basis of cost of heat in conditional equivalents is applied. The work was carried out on the basis of equipment at the Balakovo NPP gas start-up boiler room using patented connection schemes for the start-up boiler room and the nearest power unit by directing steam from the start-up boiler room through the provided connecting steam lines to the low-pressure cylinder of the main turbine unit of the nuclear power plant. The proposed option for the reconstruction of a start-up boiler room on the basis of nuclear power plants allows for the generation of peak power with high efficiency of the operation of turbine plants in a nuclear power plant and a start-up boiler room. At the same time, the price for peak energy should be higher than for the base one with sufficient workload for annual steam generation from the start-up boiler.
Yu.V. Vankov, E.R. Bazukova, N.D. Jakimov, E.G. Sheshukov, N.D. Chichirova
THE STUDY OF THERMAL DESTRUCTION OF STEAM PIPELINE’S HEAT INSULATION (Transactions of Academenergo. 2019. N 4. pp. 98-108). doi: 10.34129/2070-4755-2019-57-4-98-108.
Kazan state power engineering university
Keywords: heat losses, thermal wall method, thermal insulation destruction, steam pipe, energy saving.
The article is devoted to solving the problem of improving energy efficiency in the transportation of steam from a heat source to an industrial enterprise. The object of study is a system of transportation and distribution of thermal energy. The subject of the study – methods for assessing the state of thermal insulation of pipelines. Due to the thermal destruction of the used insulation materials, the thermal conductivity coefficient may increase by 20-30% in the first years of operation. Timely assessment of the state of thermal insulation of steam pipelines will significantly save primary energy resources. The change in the coefficient of thermal conductivity of the insulation of the steam pipe was evaluated using a device, based on the additional wall method. The developed thermal insulation properties control system is implemented in the LabVIEW environment. The article presents the results of calculating the specific heat loss of an aboveground steam pipeline taking into account the thermal destruction of insulation. The article presents the results of calculation of non-normative heat losses of the steam pipeline of an industrial enterprise.
O.V. Soloveva, N.D. Yakimov, N.D. Chichirova
INVESTIGATION OF HYDRODYNAMICS AND CONVECTIVE HEAT TRANSFER IN THE OPEN CELL FOAM MODELS OF VARIOUS GEOMETRY (Transactions of Academenergo. 2019. N 4. pp. 109-121). doi: 10.34129/2070-4755-2019-57-4-109-121.
Kazan State Power University
Keywords: open cell foam material, convective heat transfer, numerical simulation, random and ordered packaging
The work considers the gas flow in a medium of open cell foam aluminum cellular material with two different values of the porosity of the medium: and . We created models of porous media with an ordered and random structure; in both cases, we constructed a porous medium by a set of intersecting spheres. Numerical simulation of gas flow and heat transfer in a porous medium is carried out using the control volume method in the ANSYS Fluent software package (v. 19.0). The results of the calculation of the pressure drop correlate well with the results of calculations obtained by the semi-empirical equation. Because of the best mixing of the flow, convective heat transfer is more intense in the model of a porous medium with a random arrangement of cells. The open cell foam material with random packing and with the porosity equal to 0.9 provides the lowest pressure drop and increases the value of heat transfer. In a porous medium of any geometry, the Nusselt number increases with increasing Reynolds number. Moreover, open cell foam material with a random arrangement of pores in space and a maximum porosity of the medium is preferable for use as a heat exchanger.
|ECONOMICS, ECOLOGY, INNOVATIVE TECHNOLOGIES AND PROCESSES IN POWER ENGINEERING|
S.S.Timofeeva, S.I. Islamova, D.V. Ermolaev
COMPOSITE FUEL BASED ON PEAT AND WOOD WASTE (Transactions of Academenergo. 2019. N 4. pp. 122-132). doi: 10.34129/2070-4755-2019-57-4-122-132.
e-mail: email@example.com, firstname.lastname@example.org, email@example.com
Institute of Power Engineering and Advanced Technologies – Subdivision of the Federal Research Center «Kazan Scientific Center of Russian Academy of Sciences»
Keywords: peat, sawdust, composite fuel, briquettes, forming, properties.
In the article the experimental studies of the production of composite fuels based on peat and wood additives were carried out. Valley peat and high-moor peat of low quality were selected as the feedstocks. For the forming briquettes, softwood additives were used. The research results showed that wood additives to peat briquettes can improve the thermotechnical properties of the fuel.