Issue 2 (142)
Section 1. Refrigeration engineering
А. V. Doroshenkо, D. N. Cheban
THE UTILIZATION OF POROUS CERAMIC AT THE EVAPORATIVE COOLING AND COMBINED SYSTEMS THEORETICAL ANALYSIS
The creation of combined refrigeration system based on integration (rational combination) of natural evaporative cooling and artificial (traditional compression cooling) can reduce the actual energy consumption and significantly improve the characteristics of cooler by reducing the temperature of condensation in the refrigeration machine (RM). Such combined refrigeration systems can significantly reduce or reduced to zero the need to feed with fresh water relatively of evaporative cooling. The analysis of the characteristics of the combined systems, based on the authors' experimental results and advanced calculation programs is presented in this paper. On the average, the new generation of refrigeration systems reduces energy consumption by 14 ÷ 60% and significantly improves environmental performance.
Keywords: Evaporative cooling – Porous ceramics – Combined refrigeration system.
V. V. Klimenko, S. V. Lopatenko
THE EFFECT OF HYDRODYNAMIC AND SURFACE FORCES ON THE COAGULATION COMPONENT OF HYDRATE FORMATION KINETICS
The influence of hydrodynamic and surface forces on coagulation in the growth of gas hydrates is considered. The evaluation of the operating forces contribution on the particles interaction process is accomplished. The equations for determination of the effectiveness of gas hydrates coagulation component growth at the diffusive and hydrodynamic mode of particles deposition are given. the relationship of hydrate formation kinetics with technological and design characteristics of the mold is shown for mixing mold in the case of hydrate coagulation component growth prevailing.
Key words: Gas hydrate and ice gas hydrate capsules – The problem of non-stationary heat conductivity – Boundary conditions of the third sort.
Yu. А. Ocheretyany
SPECIFICATION OF THE ALTERATIONS IN THE THERMAL CHARACTERISTICS OF VESSELS REFRIGERATION APPLIANCES IN THE PROCESS OF THEIR MAINTENANCE
The issues relating to the thermal characteristics specification and the alterations identification in the real cycle of the vessel refrigeration plants during their operation are considered in the article.
Keywords: Thermal performance - Real cycle - Vessel refrigerator plant
Section 2. Power engineering and energy saving
А. R. Antonova, V. Kh. Kirillov
THEORETICAL AND EXPERIMENTAL STUDIES OF FILM FLOWS IN HEAT-MASS EXCHANGE APPARATUSES (EVAPORATIVE COOLERS, GAS-LIQUID SOLAR COLLECTORS, REGENERATORS) OF ENERGY SYSTEMS
In the article the problem of film flows on vertical and inclined surfaces heat-mass exchange devices that are part of drying and cooling circuits of solar heat-absorption systems are considered. For the first time the analysis of characteristics of film flows, including the issues of stability in a countercurrent gas-liquid interaction, the gravitational flow on inclined surface heat sink gas-liquid collectors SAG-g is performed. The data relative to the thickness of liquid films and characteristics of wave for SAG-g needed for analysis and design of solar collectors and systems in general are obtained.
Keywords: Solar energy – Solar collectors – Film flows.
I. L. Boshkova, Т. Yu. Dement’eva, Е. V. Georgiesh, Е. N. Kolobkov
MEASUREMENT OF DIELECTRIC CHARACTERISTICS OF VEGETABLE MATERIALS
The features of the resonance method for the study of polar dielectrics in the microwave electromagnetic field frequency of 2450 MHz were studied. The measurements of the resonance frequency and the quality factor of the dielectric resonator without a sample (plant material), and the sample placed in the cavity performed. According to the obtained values of the resonant frequency and the quality factor calculated dielectric properties of wet plant material. The influence of the temperature of the material and its density on the relative dielectric constant ε ', loss tangent tgδ and loss factor ε'' was determined.
Key words: Dielectric properties – Microwave frequencies – Plant material – Resonance method – Temperature – Density.
А. V. Doroshenkо, Marshan Yaser, V. P. Danko
METAL-POLYMER SOLAR COLLECTORS FOR MULTIFUNCTION POWER SYSTEMS
The metal-polymer type of flat plate solar collector is developed and the experimental study of its characteristics on the full-scale samples SC, differing in the number of transparent coatings is performed. It is shown that the performance of SC of new type are the best against the background of the existing world developments based on polymeric materials, and the use of copper multichannel structure as the heat receiver improves the reliability of operation due to solving the problem of heating medium uneven distribution through the heat receiver channels.
Keywords: Metal-polymer solar collector – Multi-channel cellular structure – Plastic microcapillary films
V. V. Milovanova
APPLICATION OF MODERN CONSTRUCTION MATERIALS IN GAS TURBINE INSTALLATIONS
The requirements for structural materials used in gas turbine installations are considered in the article, the data on their properties and methods of manufacture are summarized. Also in this article the comparing of different structural materials used in gas turbine installations is given, and the prospects for their development and methods of improvement are highlighted.
Key words: Gas turbine installation - Construction material - Nickel alloy - Mono-crystal material - Light mono-crystal
Ngo Minh Hieu, А. Е. Denisova
BIOGAS PLANTS FOR VIETNAM CONDITIONS
The prospects for the use of biofuels for the conditions of Vietnam are considered. The ways of increasing the efficiency of energy generation systems using biofuels are identified. The engineering and economic assessment of biogas plants that provide heat, hot water and the production of organic fertilizers is performed.
Keywords: Biofuels – Gas turbine – Biogas plant – Heat – Hot water – Fertilizer production.
N. А. Prusenkov
PREREQUISITES FOR REVISION OF DBN B.2.6-31: 2006 FOR JUSTIFICATION OF POSSIBILITIES FOR LOSSES REGULATION BY MOVABLE FLOW
Existing legislation creating barriers: - excludes energy flow in closed fibers enclosing structure; - neglects of the medium displacement during operation; - involves changing of thermal characteristics of multi-layer fences only at the stage of the capital costs. To expand the capacities of regulation losses in the transition of the heat flow between their surfaces, during the maintenance, the existing DBN should be supplemented by regulations and guidelines to attract verified by theory and practice innovations: - the use of mobile component layers; - regulation of energy losses during the transition of the heat flux during the maintenance stage; - compensation for loss of energy due to revenues from external sources.
Keywords: Multi-layer cladding – Energy transfer – Movement of environment – Moving layer – Closed component.
Section 3. Refrigerating and accompanying technologies
А. V. Doroshenkо, S. Yu. Vasyutinsky, V. P. Danko, М. А. Glauberman
SOLAR DRAINAGE-EVAPORATIVE REFRIGERATION SYSTEM ON THE BASIS OF HEAT AND MASS EXCHANGE APPARATUS WITH SLIDING NOZZLE. PART II. EXPERIMENTAL STUDY OF HEAT AND MASS TRANSFER PROCESSES IN THE EVAPORATIVE COOLERS WITH SLIDING NOZZLE
The circuit diagrams of solar heat-cold supply and air conditioning systems with usage of heat- and mass transfer devices based on fluidized packed layers of "gas-liquid-solid" were developed. The usage of such apparatuses in drainage part of the solar cooling systems provides the opportunity to work on the water absorbent solution without the risk of deposits occurrence on operation surfaces and the apparatuses walls. Earlier were considered the main modes of fluidization applied to the new column design principles of the heat- and mass transfer apparatus. This paper presents the results of experimental studies of processes in cooling loop solar absorption systems heat- and mass transfer devices.
Keywords: Evaporative coolers – Cooling efficiency – Solar systems.
WATER DESALINATION BY FREEZING
The technology of water desalination through freezing using the freezing settings that allow to increase the intensity of heat and mass transfer processes during crystallization and separation of ice from concentrate. For these plants the new types of crystallizators and desuraging-washings columns are used that diminish sizes and weight of plants and allow to lower the cost of water desaltation are used.
Keywords: Water desaltation – Desuraging-washings column – Freezing out plants – Crystallization
V. А. Nayer, М. B. Kravchenko, А. V. Rozhentsev
CRYOGENIC LIFE SUPPORT SYSTEMS – THERMODYNAMIC ANALYSIS, MATHEMATICAL MODEL, PROTOTYPES TEST RESULTS
Exergy reserves in the compressed gas and cryogenic underwater apparatuses are considered in the article. It is shown that the exergy reserve in the cryogenic apparatuses might be 5-6 times greater than in conventional aqualungs and it may be used practically. The schemes with the semiconductor thermopile for electricity generation, as well as schemes for heating and cooling of the diver are presented. Both thermodynamic and mathematical models of the cryogenic breathing apparatus are proposed. The conducted experimental research of the prototypes proved their efficiency and allowed to determine their actual performance characteristics. Cryogenic devices experimental and estimated performances comparison showed that they adequately coincide and that the latter may be used at the design stage of such systems.
Key words: Breathing apparatus – Liquid air – Cryolung – Life-support – Thermal shielding
S. N. Petushenko
MODERN STATE OF THE EQUIPMENT AND TECHNOLOGY OF LOW TEMPERATURE PROCESSING AND STORAGE OF SMALL-SEEDED CULTURES GRAIN CROPS
The analysis results of artificial cold use for the processing and storage of grain are given. It is shown that the low temperature treatment improves the quality and shelf life of grain, reduce energy costs.
Keywords: Grain cooling – Refrigeration machines – Quality of grain storage.
Section 4. Automatic, computer and telecommunication technologies
S. N. Ikonnikov, V. А. Lapin, D. А. Makoveenko
SPECTRUM DISTRIBUTION PROBLEMS AT THE GLOBAL LEVEL
The analysis of the distribution of radio frequency resource to various radiocommunication services as well as scientific and technical challenges associated with the prospective spectrum management at the global level are given in the article.
Keywords: ITU – RFR – Radiocommunication Service – Frequency band
V. V. Antonyuk, О. V. Drozd, І. M. Nikolenko
COMPUTER SYSTEMS DIGITAL COMPONENTS HARDWARE MODEL
Particularities in structure of the hardware model on FPGA, representation in it of the object of diagnosis and served blocks for solving tasks of analysis of the digital components of computer systems are considered. The served blocks provide checkability of the object of diagnosis and reliability of the received results of researches. Facilities of the hardware model in a task of the test-pattern generation are analyzed.
Keywords: Hardware model – FPGA – Object of diagnosis – Digital component – Test-pattern generation – Checkability – Safety-critical systems.
А. N. Martynyuk, Waseem Аl Sharif
TEST MODELS FOR PETRI NETS FORMULATIONS
The test models for Petri nets formulations, enabling to compose the test procedures for arbitrary structures of Petri nets are proposed. The models are based on the analysis of implemented and broadcasted test behavior of Petri nets, which includes the identification of the reference positions.
Keywords: Petri Nets – Formulations – Identifiers – Tests.
А. А. Bondarenko, О.А. Rodik
ACCESS NETWORK TOPOLOGICAL STRUCTURE OF SYNTHESIS AUTOMATED PROCEDURE
Main problems of access networks' design are given in the paper. Statement of the task of automated procedure for access network's topological structure's synthesis development is accomplished. Scheme of the procedure's proceeding is developed. All iterations of the procedure are described.
Keywords: access network, the access node, network design, networks synthesis, telecommunication networks.
А. А. Gursky, V. А. Denisenko, А. Е. Goncharenko
REFRIGERATION TURBO COMPRESSOR AS AN OBJECT OF AUTOMATIC CONTROL SIMULATION FEATURES
Specifications and features of refrigeration turbo compressor plant are presented in the article. The analysis of the simulation results of the object static modes is given.
Keywords:Turbo compressor – Refrigeration plant – System with controlled structure
M. O. Drozd
THE PROBLEM OF CONTROLSUITABILITY OF DIGITAL COMPONENTS IN THE SYSTEMS OF CRITICAL APPLICATIONS
The problem in checkability of the digital components in safety-critical systems is considered in content of threat created in the functional safety of the objects with increased risks. The particularities of estimation in checkability for both imitated and on-line testing of the digital components in safety-critical systems like two-modes computer systems is analyzed. The expedience in identification of the potentially dangerous points for the digital components is shown. Conditions in detection of the potentially dangerous points for the digital components in structure of safety-critical systems are determined.
Keywords: Safety-critical computer systems – Digital components – Normal and emergency modes – Checkability – Potentially dangerous points.
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L. V. Ivanova, S. А. Nesterenko
MULTISERVICE NETWORKS HETEROGENEOUS SEGMENTS REENGINEERING TECHNOLOGY
The task of heterogeneous network segment rational structure development by criterion “productivity/cost” is formulated. The method of heterogeneous multi-service networks segment design in specialized CADD environment is developed.
Keywords: Metamodel – Heterogeneous network segment – Unblocked structure ‒ Rational structure ‒ Method of development ‒ Tools ‒ CADD.
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О. V. Oleschuk, V.М. Khmelevskoy
SOFTWARE AND HARDWARE MEANS FOR MULTIDIMENSIONAL AREA MAPPING
The specific features of the three-dimensional area mapping organization with the possibility of targeting based on a composite map are considered. Required hardware components and processing algorithm adopted from various sensors are identified. In addition, the issues of measuring systems self-calibration, noise immunity, reliability performance and reliability are solved.
Keywords: Mapping ‒ Hardware components ‒ Sensor ‒ Self-calibration ‒ Noise immunity ‒ Reliability of results.
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А. S. Smirnova
AN APPROACH TO THE CONSTRUCTION OF AN INFORMATION NETWORK USER MODEL AS BADLY FORMALIZED OBJECT
An approach to the construction of an information network’ user model as badly formalized object is suggested in the article. The results showing the formation of classes of users obtained by developed software, which is based on methods of growing pyramidal networks and cluster analysis are given in the work. These results can be used to create classes of users of information networks, based on their needs, they can also be used for further modeling of information networks in general.
Keywords: Networks‒User‒Badly formalized objects‒Methods of growing pyramidal networks‒Clustering.
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Т. P. Stanovskaya, А. О.Stanovsky, А. V. Toropenko, G. V. Naleva
METHOD FOR DISCLOSURE OF UNCERTAINTY IN THE COMPLEX OBJECTS
The method for diagnosis of complex redundant wireless networks, whose structure suffers from damage during the life cycle is developed. The method is based on the realization of hidden Markov models, providing the systems researcher with additional diagnostic information with a high degree of probability.
Keywords: Complex object – Disclosure of uncertainty – Information evaluation.
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Т. P. Stanovskaya, М. А. Dukhanina, Yu. V. Shikhireva
THE INFRARED MEASUREMENT METHOD OF HEAT PARAMETERS OF CONCRETE HARDENING
For the assessment of concrete details condition at their hardening it is offered to use infrared video filming of an external surface of a detail with the subsequent parabolic transformation of the received video stream.
Keywords: Concrete ‒ Hardening ‒ Thermal processes ‒ Parabolic transformation
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А. V. Svirin
COMPUTING SERVER UTILIZATION IN THE FEDERATED HETEROGENEOUS INHOMOGENEOUS SQL-SYSTEM
Inthis paper we proposemethods toimprove the flexibility and performancecharacteristicsof heterogeneousfederatedinhomogeneousdistributed databaseby providing thenodes heterogeneous properties andoptimizing the recurring distributedSQL-queries performance.
Keywords: FederatedSRM –HeterogeneousSRM– SQL-system –Access gateways – Computing Server
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