Issue 5 (145)
Section 1. Refrigeration engineering
V.L. Bondarenko, Yu.M. Simonenko,A.P. Chuklin
CALCULATION OF MULTICOMPONENTGAS MIXTURE SEPARATION ON HOLLOW-FIBER POLIMER MEMBRANE
Calculation model presented in this work allows to determine key parameters of the multicomponent gas mixter separation process. Computing algorithms for the schemes of concurrent and countercurrent flow organization were formulated. The results of calculations for the cases of air separation and multicomponent mixture of rare gases were observed. Experimental data was compared with the results obtained from mathematical model.
Keywords:Gasmixtures – Inertgases – Membrane technologies
A.A. Vasserman, S.V. Kozlovsky, V.P. Malchevsky
THERMODYNAMIC PROPERTIES OF NINE MIXTURES OF HYDROFLUOROCARBONS AND NATURE REFRIGERANTS
The equations of state of nine mixtures of hydrofluorocarbons and nature refrigerants were compiled on the basis of experimental p,ρ,T,x- and p,T,x-dataand for two mixturesalso on the basis of the data about isochoric heat capacity. The comparison of calculated values of density and isochoric heat capacity with the experimental ones were performed and the tables of thermodynamic properties were calculated.
Keywords: Mixtures of refrigerants –– Equations of State –– Hydrofluorocarbons –– Nature refrigerants –– Binary mixtures –– Tables of thermodynamic properties.
Kogut V., Khmelniuk M., Butovskyi I.
REFRIGERATION SYSTEM FOR CONDENSATION OF HYDROCARBONS IN THE STREAM
Refrigeration system designed to condense the hydrocarbons volatile fraction vapors, particularly gasoline, is considered in the article. It is shown that the utilization of the thermopressor system allows condensing and reducing of the hydrocarbon vapors losses during charging and storage.
Keywords: thermopressor, condensation, fuel loss.
Yu. Semenyuk, V. Zhelezny, D. Ivchenko, V. Geller
The results and generalizations of thermophysical properties research for there frigerant/lubricant mixtures are summarized. The methodological aspects of the experimental studies of the thermal properties of real working media for vapor compression refrigeration machines and the general principles of the thermodynamic properties simulation for such solutions are analyzed. It is shown that the admixtures of compressor oil in the refrigerant make the efficiency parameters of compressor systems much lower. The question of a selective solubility of the multicomponent refrigerants in compressor oils is discussed.
Keywords: Refrigerant/lubricant mixtures–Thermodynamic properties – Efficiency parameters – Selective solubility
Section 2. Power engineering and energy saving
E.G. Bratuta, V.А. Tarasova, D.Kh. Kharlampydi, А.V. Sherstyuk
THERMO-ECONOMIC APPROACH TO DIAGNOSTICS OF REFRIGERATING MACHINES AND HEAT PUMPS
The technique of decomposition of exergetic flow on the "fuel" and "product" of element for the thermo- economic diagnosis chiller and heat pump is proposed. The results of an in-depth analysis of the thermodynamic heat pump with the release of endogenous and exogenous components of exergy destruction in its elements are given.
Keywords: Тhermo-economic diagnostics – Decomposition – Еxergy destruction
D.N. Kravtsov, A.A. Stopakevich
DEVELOPMENT AND RESEARCH of steam generator PGV-1000 MODEL
The article spotlights developing of the steam generator PGV-1000 model. The step responses of the model in the environment MATLAB Simulink were obtained, and the effect of changing the heat transfer surface on the dynamic characteristics of the steam generator was investigated.
Keywords: Mathematical model - Steam generator - Heat transfer - PGV-1000
study of the fresh air natural flow efficiency in the premises subjected the principles of energy saving
This article spotlights the analysis and results of air currents motion modeling in the premises using window and wall inlets as a way of achieving greater energy efficiency in compliance with air quality standards. A method for optimal air inlet position for installation to maintain the desired temperature in the room at the lowest cost is considered.
Keywords: Window ventilator - Natural ventilation - Simulation - Energy saving.
DIRECTION OF IMPROVING MULTILAYER ENCLOSING CONSTRUCTIONS
A retrospective comparison of the norms, regulating the creation of enclosing structures which stimulates addition directions design of multilayer fencing means of regulation of losses during operation due to compensation of heat revenues in the period of operation provided by the manifestation of the properties of the moving threads, bearing the energy from external sources that are not covered by previous regulations. The selected direction requires revision and implementation into the effective guidance on the fences design.
Keywords: energy saving, multi-layered fencing constructions, capital costs, movable thread closed flow, heat transfer, losses.
Section 3. Refrigerating and accompanying technologies
V.V. Klуmenko, M.V. Lychuk, M.V. Bosiy
BRANDON METHOD APPLICATION FOR OBTAINING OF HYDRATE FORMATION PROCESS KINETICS EMPIRICAL EQUATION
The expedience of the Brandon method utilization for obtaining of the empirical equation for the kinetics of hydrate formation process is substantiated. An example of processing uzing Brandon algorithm of experimental data according the rate of formation of gas hydrates at cold accumulation for obtaining the equation of the process kinetics is considered. The sufficiency of the resulting equation by Fisher’s and Student’s measures is evaluated and it is shown that it describes the rate of hydrate formation with an average fractional error of 4,8 %.
Keywords – Hydrates – The process of hydrate formation – Accumulation of cold –Brandon method – Empirical kinetic equation – Student’s test – Fisher’s test
V. P. Kochetov, О. М. Tomchyk
MATHEMATICAL MODEL OF HEAT TRANSFER IN THE PERIODIC TEMPERATURE FLUCTUATIONS IN THE CHAMBERАТ THE DIFFERENT CONFIGURATIONS PACKAGING UTILIZATION
The results of experimental studies of apples storage in packaging with liquid (water) interlayers with high thermal stability and accumulative capacity for storage fruit and vegetables are represented. According to the temperature measurements data the law of air temperature variance in the chamber is revealed, and the mathematical model of heat transfer between the product and the environment at ambient temperature variance on the periodic law is developed. The results of model calculations and their comparison with the experimental studies results are given.
Keywords: Storage of fruits – Тemperature fluctuations – Packing with high thermal inertia – Water interlayers.
Section 4. Automatic, computer and telecommunication technologies
A. Gurskiy, V. Denisenko, A. Goncharenko
Systems of refrigerating centrifugal compressorscapacity automatic control
Various systems of automated control of refrigerating machineries with centrifugal compressors are considered. Strengths and weaknesses of various refrigerating turbo-compressor plants different control systems are defined.
Keywords: Centrifugal compressor – Refrigerating machine – Automatic control system – Coordinating system
V.O. Davydov, O.B. Maksimova, T.S. Dobrovolskaya
COMPARATIVE ANALYSIS OF the genetic algorithms and dynamic programming methodS in terms of system with variable structure control PROBLEM solution
On the example of a system with a variable structure two methods of dynamic optimization are compared. As the parameters of the objective function are the reliability of the equipment used, the efficiency of this equipment utilization, as well as the cost of the equipment and the quality of the transition process. On the basis of the model the discrete optimization techniques performance results were obtained
Keywords:The method of genetic algorithm - Dynamic programming method - Generalized criterion – Heat-supply model - Variable structure of the object.
V.N. Dokykin, V.А. Pronin
The STANDS FOR EXPERIMENTAL INVESTIGATIONS OF SCREW oil-flOODed REFRIGERATION COMPRESSORS
The selection of test rig scheme for the study of oil-flooded screw compressor were studied in the article.
Key words: Oil-flooded screw compressor -Test rigs-Measurement of cooling capacity
G.N. Vostrov, A. Atie, K.A. Levenets
MODERN METHODS OF ANALYSIS AND INFORMATION PROCESSING IN COMPLEX INFORMATION SYSTEMS
The paper presents the basic strategies of analysis and information processingin management of information technology systems . The key stages for implementation of information systems and problems that arises in this case are highlighted, the number of measures for resolving them are proposed.
Keywords: information systems, databases, enterprise management, complex of information technology