NEW APPROACH FOR MODELING OF INDUSTRIAL COLUMN APPARATUSES. CHEMICAL REACTORS // Transactions of Academenergo. 2016. №4. p. 13-22.
- Boyadjiev, Chr. Boyadjiev
Institute of Chemical Engineering, Bulgarian Academy of Sciences
Keywords: Column apparatus, chemical reaction, convection-diffusion model, average concentration model, velocity radial non-uniformity.
A theoretical analysis of the effect of the velocity radial non-uniformity in the industrial column chemical reactors is presented. A numerical analysis shows, that average concentration model, where the radial velocity component is equal to zero (in the cases of a constant velocity radial non-uniformity along the column height), is possible to be used in the cases of an axial modification of the radial non-uniformity of the axial velocity component. The use of experimental data, for the average concentration at the column end, for a concrete process and column, permits to be obtained the model parameters, related with the radial non-uniformity of the velocity. These parameter values permit to be used the average concentration model for modeling of different processes.
EFFECT OF CAMERA QUANTIZATION ERROR ON FLOW VELOCITY MEASURED BY Smoke Image VelocimetrY // Transactions of Academenergo. 2016. №4. p. 23-31.
N.S. Dushin*, N.I. Mikheev*, **, О.А. Dushina*, D.I. Zaripov*,
А.А. Paereliy*, I.M. Gazizov**
*Kazan Scientific Center RAS
**Kazan National Research Technical University named after A.N.Tupolev – KAI
Keywords: optical method, smoke visualization, accuracy estimation, camera noise, quantization error, turbulent flow, Smoke Image Velocimetry, PIV
The effect of analog-to-digital converter (ADC) quantization error on the uncertainty in flow velocity fields measured by Smoke Image Velocimetry (SIV) has been analyzed. Visualization images of backward-facing step flow have been considered as a test case. Quantitative correlation between the RMS deviation of the measurement due to quantization errors and both smoke image intensity nonuniformity in a considered window and interrogation window size has been established. Quantization error has been shown to have no effect on average flow velocity measurement but to cause additional random noise in velocity estimation. For the smoke image intensity nonuniformity and the range of interrogation window sizes that have been chosen to experimentally estimate velocity vectors, the relative RMS uncertainty was 0.027…0.37% of core flow velocity.
Yu.A. Kirsanov*, A.Yu. Kirsanov **, A.E. Yudakhin***
MULTIPERIOD TWO-DIMENSIONAL HYPERBOLIC HEAT CONDUCTION BOUNDARY PROBLEM OF THE THIRD KIND // Transactions of Academenergo. -2016. -N 4. – P.P. 32-41.
* FSBIS Kazan Scientific Center of the Russian Academy of Sciences, Kazan
** FSBEI HE Kazan National Research Technical University (KNRTU-KAI) named after A.N. Tupolev, Kazan
*** FSBEI HE Kazan Power Engineering University, Kazan
Keywords: boundary-value problem, the hyperbolic heat conduction, transient process, thermal relaxation, thermal damping, experiment, measurement.
The mathematical model of the multiperiod transient process in the round disk is presented in the form of a decision of a hyperbolic boundary value problem of heat conduction with the third kind boundary conditions. The experimental setup for registering transient thermal process in a center and on surface of a disk of polymethylmethacrylate was described. The method for Bio numbers determination in each period of registered transient process was proposed. Thermal relaxation time and thermal damping time were found by minimization of a functional, which was a sum of squares of the differences calculated and measured temperatures.
K.E. Podlipnova, N.M. Nikitin
NUMERICAL STUDY OF HEAT TRANSFER FROM A FINNED SURFACE // Transactions of Academenergo. -2016. -N 4. – P.P. 42-49.
Samara state technical University
Keywords: finned surface, heat transfer, numerical simulation, air heater, laminar flow, draft losses.
Presented work is devoted to numerical simulation of heat transfer from a flat surface in a channel with complex profile in conditions of laminar flow. An adequacy of the model was proved by comparison with data adopted from experimental study of plate-fin heat exchanger. The steady state solution of the problem showed a stable distribution of velocity profiles in considered range of Reynolds numbers. Common locations of stagnant zones were revealed as well. Pressure distribution across the width of the channel was discussed.
А.Z. Daminov, Yu.V. Karaeva
PREDICTION OF ENERGY SUPPLY FOR A SETTLEMENT // Transactions of Academenergo. -2016. -N 4. – P.P. 50-58.
Kazan Scientific Centre of the Russian Academy of Sciences
Keywords: algorithm, prediction, energy supply, settlement.
The developed mathematical model makes it possible to carry out a long-term prediction of energy supply for a settlement, i.e. to form various variants of perspective fuel and energy balance. The mathematical model is based on the use of information network, which is a directed graph with edges representing the material and energy flows. In this case each node corresponds to the energy balance and price equations. The computer program is written on the basis of the developed mathematical model and calculation algorithm for predicting the development of the energy sector of the settlement. The program allows to carry out a comprehensive and systematic analysis of the energy supply system of the settlement in the interactive mode.
ABOUT THE APPROPRIATENESS USES OF THE CATALYTIC HEAT GENERATORS FOR DECENTRALIZED HEATING SURFACE // Transactions of Academenergo. -2016. -N 4. – P.P. 59-66.
Ulyanovsk state technical University
Keywords: catalytic heat generators, reliability, economy, safety of ecology, the feasibility of using.
In this article were analyzed the statements of the developers and manufacturers of catalytic heat generators about high economy, safety of ecology and reliability of these devices. In most cases, these assertions are unsubstantiated and are contrary to the fundamental laws of physics and chemistry. An example of operation of catalytic heat generators in Ulyanovsk, which showed extremely low reliability.
- Z. Aminov, A. A. Gudym
LOOKUP TABLES PROPERTIES DISSOCIATED WATER VAPOR FROM THE REFERENCE TEMPERATURE OF 0 °C // Transactions of Academenergo. -2016. -N 4. – P.P. 67-76.
e-mail: email@example.com, firstname.lastname@example.org
Saratov center of science of Russian academy of sciences
Keywords: steam, enthalpy, entropy, formation heat, reference temperature, thermal power installations
For the development of hydrogen technology on receipt high-temperature steam, based on the oxidation of hydrogen in oxygen is necessary to determine the thermodynamic properties of dissociated water vapor. Existing table of thermophysical properties of dissociated steam composed at a reference temperature of 0 K, while worksheets undissociated couple (to a temperature of 1250 K) composed with a reference temperature of 0 °C. Since the publication by the authors table thermodynamic parameters (enthalpy and entropy) dissociated couple with the reference point of 0 °C there is a need to supplement their specific heat and specific volume. The paper presents a table of properties of dissociated water vapor in the temperature range of 1250-4000 K, pressure 0.01-20 MPa reference temperature equal to the temperature of water at the triple point 273.16 K adopted in the international system of equations for calculating the properties of non-dissociated steam. The tables at the same temperature reference are calculated thermodynamic parameters and specific heat for equilibrium chemically reacting mixture. In contrast to existing tables thermal properties of dissociated steam enthalpy in the tables throughout the range of options under consideration is positive, that allows you to perform thermodynamic calculations of heat engines cycles by reacting dissociated couple with the external environment, in particular, when mixing the dissociated steam undissociated.
N.D. Chichirova, Yu.V. Abasev, N.G. Shagiyev
THE IMPACT OF COMPLEXING AGENTS THERMAL DEGRADATION PRODUCTS ON THE CORRECTIVE TREATMENT OF THERMAL POWER PLANT HEAT TRANSFER AGENT // Transactions of Academenergo. -2016. -N 4. – P.P. 77-84.
Kazan state power university
Keywords: complexing ability, thermal destruction of complexing organic acids, correctional water treatment of thermal power plants, iminodiacetic acid, phosphonoacetic acid.
There are given the results of the influence of the chelators and their sodium salts thermal decomposition in aqueous medium equilibrium processes of thermal power plants. As a result of the thermodynamic calculations ionic compositions of aqueous solutions containing 1-Hydroxyethane-1,1-diphosphonic acid (HEDP) and phosphonoacetic acid (PAA) were defined. The dependence of the pH of PAA and its sodium salts aqueous solutions from reactant concentrations and pH ranges of thermodynamic stability iminodiacetic acid (IDA) with metal cations including in the constructural materials were found. It is necessary to take into account the effect of thermal degradation products in aqueous systems at the correctional treatment of thermal power plant heat transfer agent.
V.N. Shlyannikov, R.R. Yarullin, I.S. Ishtyryakov
THE EFFECT OF TEMPERATURE ON THE FATIGUE SURFACE CRACK GROWTH IN ALUMINUM ALLOY D16T // Transactions of Academenergo. -2016. -N 4. – P.P. 85-97.
Kazan Scientific Centre of the Russian Academy of Sciences
Keywords: aluminum alloy D16T, surface cracks, different temperatures, crack growth, plastic SIF
The variation of crack growth behavior is studied under cyclic axial tension fatigue loading for the different temperatures conditions. By experimental studies for considered temperature conditions the relations between the crack sizes on the free surface of specimen, crack opening displacements, crack growth rate and aspect ratio were obtained. These relationships are useful for automation of experimental studies of surface crack growth. The classical elastic stress intensity factor (SIF) and new plastic SIF approach was applied to the fatigue crack growth on the free surface of the hollow specimens as well as the deepest point of the semi-elliptical surface crack front. As result principal particularities of the fatigue surface crack growth rate as a function of temperature conditions are established.
V.N. Shlyannikov, A.P. Zakharov
GENERALIZED features for the surface and through the thickness cracks in alluminum alloy D16T UNDER BIAXIAL LOADING // Transactions of Academenergo. -2016. –N 4.-P.P. 98-107.
Kazan Scientific Center of Russian Academy of Sciences
Kazan National Research Technical University named after A.N.Tupolev – KAI
Keywords: biaxial loading, cruciform specimen, crack growth rate, plastic stress intensity factor, generalized coordinates
Fatigue surface crack growth was studied through experiments and computations for aluminum alloy D16T. Subjects for studies are cruciform specimens under different biaxial loading with external semi-elliptical surface crack. The generalization of the experimental data for crack growth rate in cruciform specimens is given by a fatigue fracture diagram in the dimensionless coordinates. The experimental and numerical results of the present study provide an opportunity to explore the suggestion that crack growth rate may be represented by the plastic stress intensity factor, rather than the magnitude of the elastic SIF alone.
A.S. Limanskiy, V.V. Takmovtsev, S.B. Dzhoraev
SELECTION AND DESIGN ANALYSIS OF CHARACTERISTICS OF UTILIZATION TURBOCOMPRESSOR PLANT WHEN WORKING TO GETHER WITH DRIVING GAS TURBINE ENGINE // Transactions of Academenergo. -2016. –N 4.-P.P. 108-119.
e-mail: Alimanskii@yandex.ru, email@example.com, Sunnetbiz@mail.ru
Kazan National Research Technical University named after A.N. Tupolev – KAI
Keywords: gas turbine engine, utilization turbocompressor, energy efficiency, temperature and flow rate of the working medium, specific effective work, power and efficiency.
Numerical study results of joint usage of special utilization turbocompressor (UTC) and 20 domestic energy and industrial driving gas turbine engines (GTE) used at gas pumping stations are presented. Application of UTC allows using the exiting heat of the driving GTE which is a part of GTP by heating the air after compressor in the utilization heat exchanger. Conducted analysis of the calculation results showed that the useful effect is the produced additional electrical energy its power gain can reach up to 10% of the power of the driving GTE .
- Shlyannikov1,2, A. Zakharov1, L. Guetsov3
CRACK GROWTH IN HEAT-RESISTING SINGLE-CRYSTAL SUPERALLOY VZHM4 FOR TEMPERATURE RANGE // Transactions of Academenergo. -2016. –N 4.-P.P. 120-127.
1Kazan Scientific Center of Russian Academy of Sciences
2Kazan National Research Technical University – KAI
3Saint-Petersburg State Polytechnical University
Keywords: Heat-resisting single-crystal superalloy VZHM4, temperature, crack growth rate.
The results of experimental studies of the crack growth rate under cyclic loading in a compact samples of the single-crystal superalloy VZHM4 in the temperature range 20-1000°C are presented. Measurement technique for growing crack length in the high temperature furnace based on an electrical potential difference method. The tests found that the crack growth rate at elevated temperature less than under normal conditions, as evidenced by statistical values of the constants of linear parts of fatigue fracture diagrams.
V.N. Shlyannikov, A.V. Tumanov, A.M. Tartygasheva
FORMULATION AND BACKGROUND OF A GOVERNING PARAMETER FOR DAMAGE ACCUMULATION DURING CREEP // Transactions of Academenergo. -2016. –N 4.-P.P. 128-135.
Kazan Scientific Center of the Russian Academy of Sciences
Keywords: damage, creep, state equations
The model of a creep stress-strain state based on the governing parameter of damage accumulation function is proposed. The elaborated model is integrated into the finite element code ANSYS. The results of calculations of the stress-strain state with internal structural damage are presented for the cracked plate. The comparison of solutions for various values of the governing parameter of damage accumulation is presented. Distributions and behavior of the damage fields near the crack tip are obtained as a function of the creep time.