Issue 1 (141)
Section 1. Refrigeration engineering
V.I. Knyazyuk, А.E. Lagutin, P.F. Stoyanov
STUDY OF THE FINNED TUBES PACKETS WITH CROSS SLOPING RIBS THERMAL CHARACTERISTICS
This paper presents the results of experimental determination of the finned tubes packets with cross sloping ribs heat transfer coefficients. Different layout solutions of tubes in packets are considered. Factors that influence the heat transfer of fin tubes with inclined fins are evaluated. A comparison of theoretical and experimental values of the efficiency of the rib is conducted.
Keywords: Fins; Heat transfer;Efficiency;Experiment.
EFFECT OF NANOSTRUCTURED MATERIALS ON TRANSFER PROCESSES IN CONSTRUCTAL MEDIA
The influence of nanostructured materials on heat transfer enhancement in cooling systems of electronic equipment is considered. Design criterion based on the constructal conception of heat conducting paths minimization at given space domain is applied. The cooling performance assessment of a microchannel heat sink with dendritic structure is given. Further enhancement of heat transfer coefficient initiated by nanofluid application is discussed. To evaluate temperature fields in dendritic transport networks with nanostructured materials more accurately computer fluid dynamics methods are used.
Keywords: Nanostructured materials; Constructal media; Nanofluids; Heat transfer coefficient; Microchannels.
Section 2. Power engineering and energy saving
А.V. Doroshenkо, V.I. Milovanov, S.S. Silich
DEVELOPMENT OF GAS-LIQUID SOLAR COLLECTORS FOR THE ALTERNATIVE REFRIGERATION SYSTEMS
The basic circuits of multifunctional solar systems of drainage of air, heating (hot water supply and heating), cooling and air conditioning are developed on the basis of open absorption of a cycle from a straight line by regeneration absorbent. The basic decisions for new generation of gas-liquid solar collectors are developed. The analysis of thermal losses is executed in gas-liquid solar collectors
Keywords: Multifunctional systems; Solar energy;Solar collectors;Regeneration.
А.V. Doroshenkо, O.A. Lisogurskaya, М.V. Rozum
MULTISTAGE EVAPORATIVE COOLERS FOR REFRIGERATION AND CONDITIONING SYSTEMS
The concept of gases and liquids multi-stage evaporative coolers creation based on multi-channel monoblock polymer structures was developed. The indirect types of coolers in normal and regenerative options are used as the basic elements in them. Natural limit of the cooling in such systems is the outside air dew point, which significantly enhances the possibilities of the evaporative cooling technology in general, and allows us to solve a number of problems of the refrigeration and air conditioning equipment with a significant reduction of energy consumption for the process. The theory of joint heat and mass transfer in indirect evaporative cooling was examined. The principle of design of individual monoblocks, as well as multi-stage blocks, was developed and recommendations to the design of a new generation of evaporative coolers were made. Preliminary analysis of the possibilities of the evaporative coolers applying to the solution of problems of air conditioning was made.
Keywords: Evaporative cooler; Multi-stage scheme; Monoblock; Multichannel; Joint heat and mass transfer.
CONVECTIVE HEAT EXCHANGE IN CRYSTALLIZERS ANDMELTERS OF GAS HYDRATE TECHNOLOGICAL INSTALLATIONS
In article it is consideredconvective heat exchange in crystallizers andmelters of gas hydratetechnological installations from positions semiempirical theories of turbulenttransfer. It is received generalized semiempiricals the equations for calculation convective heat exchange of three-phase system « hydrate the agent- water- gas hydrate » in crystallizers and meltersin case of compulsoryturbulization streams by mixers orbarbotage.
Key words: Convective heat exchange ;Semiempirical theories of turbulenttransfer;Energy dissipation; Three-phase system "hydrate the agent-water-gas hydrate"; Crystallizer; Melter.
SCHEME OF HEAT TRANSFER THROUGH A MULTILAYER FENCE WITH SUPPLY OF "MOBILE" COMPONENT
Rethinking the transfer principles of energy flow component between the surfaces of the building envelope, amid renewed abroad (2002) the use of ventilation means to reduce losses, requires the addition to the existing 2006 SBN "Thermal insulation structures" normative data, providing the possibility of compensation for losses at a constant, as is required by this norm, thermal resistance acquired during construction to take into account the additional energy input during the operation to improve the fencing, which stimulates the revision of the description of the process and the provisions of SBN.
Key words: Distribution; Super-positioning; Compensation; Scheme; Norm; Supplement; Thermal resistance
Ngo Minh Hieu
ANALYSIS OF VIETNAM ENERGY AND ECONOMICS INTERDEPENDENCE
The features of power consumption in Vietnam to assess the effect of the gross domestic product (GDP) on the power consumption process are considered. The model allowing to assess the response of power consumption on economics is proposed. The ways to improve energy efficiency and economic power complex in Vietnam are targeted. The ways of increasing the efficiency of energy generation systems using renewable energy sources are targeted.
Keywords: Electricity; Economics; Power complex; Renewable energy sources; Bio-resources.
DISPERSED SYSTEMS MOLECULAR DYNAMICS 1. SIMPLE DISPERSION MEDIUM
The problem of the dispersion systems investigation by the molecular dynamics method (MDM) is discussed. Based on the results of performed molecular dynamics experiments, and taking into account the experience with this method, as well as the capabilities of modern computer technology, the great prospects of the MMD applied to the study of the dispersed particles of isotropic and anisotropic dispersion systems properties, structure, and dynamics including the behaviour of nanoparticles and nanofluids is concluded.
Keywords: Dispersion system; Molecular interactions; Моlecular dynamics method; Structure; Precision of molecular dynamics experiments; Nanoparticles; Nanofluids; Nanotechnologies.
Section 3. Refrigerating and accompanying technologies
V.J. Labay, О.V. Labay, D.І. Garasim
METHOD OF INDOOR MICROCLIMATE PARAMETERS DETERMINATION AT SPLIT-CONDITIONERS UTILIZATION
The method of determination with I-d – parameters diagram extension of indoor microclimate which was created with air split-conditioners was elaborated in this article.
Keywords: Parameters of microclimate ;Air split-conditioner; I-d – diagram.
Section 4. Automatic, computer and telecommunication technologies
Yu.V. Drozd, O.V. Drozd, M.O. Kuznetsov
NATURAL RESOURCES UTILIZATION OF FGPA-ORIENTED PROJECTS FOR CALCULATION RESULTS RELIABILITY INCREASING
The issue of development of the target resources for solving the tasks of computer systems design and their components - models, methods and means and also their features which compose natural resources is considered. The expansion of the preserved results method which favors activities of natural resources is shown on example of modern co-design of digital components on FPGA. The natural resource of LUT-oriented architecture which allows to increase masking the faults and reliability of the calculated results by the method of variants is detected.
Keywords: Target and natural resources; Co-design of digital components; LUT-oriented architecture; The method of variants; Masking the faults; Reliability of the calculation results.
COGNITIVE MODEL OF AIR CONDITIONING SYSTEM FUNCTIONAL THREATS AND RISKS ASSESSMENT
The cognitive model for simulation of functional assessment of the threats and risks arising at air conditioning system operation is proposed in the article.
Keywords: Survivability; Air conditioning system; Cognitive model.
S.A. Glukhova,S.L. Zinovatna
SURPLUS DATA INTEGRITY ENSURING TASK FORMALIZATION AT CARRYING DATABASE DENORMALIZATION
Rules and algorithms for realization of data integrity support facilities at the use of ascending and descending denormalization are presented. Automatic trigger creation is provided for database relations, for which denormalization that promotes quality of database restructurization is executed
Keywords: Data base; Data integrity; Denormalization; Trigger.
TECHNOLOGY STATION ELECTRICAL POWER EQUIPMENT PROPERTIES IN THE OPERATIONAL HAZARDS CONTEXT
The paper analyzes the processes of industrial power complex, conditioned by the properties of induction motors to create a reverse flow of energy after a network failure and the expediency of suppressing reverse energy flow in the event of a hazardous electrical conditions is substantiated.
Keywords: Electrotechnical complex; Induction motor; Actuator; Back-to-network power generation; Emergency condition; Protective disconnection.
I.P. Panfilov, Yu.V. Fleita
SYNTHESIS OF THE REFERENCE SIGNAL FOR THE CHANNEL WITH THE CONCENTRATION AND FLUCTUATING INTERFERENCE
The method of synthesis of correlation receiver optimal reference signal under the influence of concentrated and fluctuating interference is considered.
Keywords: Reference signal; Concentrated interference; Fluctuation interference.
Yu. Yu. Sulima, О. V. Drozd
EVALUATION AND METHOD OF INCREASING CONTROL SUITABILITY OF DIGITAL COMPONENTS IN CRITICAL APPLICATION SYSTEMS
The problem of the low control suitability for the digital components of the safety-critical Instrumentation and control systems aimed at the support in the functional safety of the objects with increased risk is considered. The estimation in control suitability of the digital components in a normal mode and a method of its increase by the way of transformation of non-checkable points of a circuit in checkable and partial checkable ones is offered. The method shows maximum increase of checkability for least checkable digital components guaranteeing the level which exceeds 50%.
Keywords: Safety-critical Instrumentation and Control systems; Digital components; Normal mode; Control suitability; Suitable and partial suitable points.
О.І. Bodyul, Е.І. Vinogradova, V.B. Vladimirova, O.S. Bodyul
PALEOECOLOGICAL DATA PROCESSING SOFTWARE
The software for the paleovegetation regional geographic distribution reconstruction based on the method of biomization with palinologycal materials research experimental data utilization was proposed.
Keywords: Software; Timing rows; Biomization method; Palinologycal data