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- ДокументPOLYMERIC MATERIALS FOR SOLAR ENERGY UTILIZATION: A COMPARATIVE EXPERIMENTAL STUDY AND ENVIRONMENTAL ASPECTS(2016) Alexander Doroshenko, Kostyantyn Shestopalov, Ivan Mladionov, Vladimir Goncharenko, Paul KoltunFull-scale metal solar collectors and solar collectors fabricated from polymeric materials are studied in present research. Honeycomb multichannel plates made from polycarbonate were chosen to create a polymeric solar collector. Polymeric collector is 67.8% lighter than metal solar collector. It was experimentally shown that the efficiency of a polymeric collector is 7–14% lower than a traditional collector. An ecologically based Life Cycle Assessment showed the advantages of the application of polymeric materials in the construction of solar collectors.
- ДокументCOMPLEX QUALITY CRITERION OF CONTROL OF THE INTELLECTUAL SERVICES PROVISION IN NGN(2016) N. O. Kniazieva, S. V. ShestopalovThe paper is dedicated to intellectual services provision control quality comparison by the intellectual superstructures with centralized and decentralized control principles in NGN. The necessity of three parties interests consideration, namely: service providers, network equipment suppliers and network users is pointed out. The method of complex quality criterion formation is proposed.
- ДокументA STUDY INTO ICE BUILD-UP AND MELTING ON VERTICAL COOLED PIPES(2016) Y. Zasiadko, O. Pylypenko, A. Forsiuk, R. GryshchenkoThe use of cold accumulators based on the principle of ice build up on the cooled surfaces during off-peak periods and ice melting during on-peak periods is an effective method of electricity bills reduction. Within comparatively short periods of on-peak demand a noticeable amount of thermal energy related to ice melting is to be released, it becomes clear that not only sizing of ice accumulators based on balance calculations is actual, but also the determination of time periods of ice accumulation becomes critical. This work presents experimental unit for obtaining data on the ice build-up on the vertical cooled pipes and later on to continuously register data on the ice thickness diminishing at the regimes of ice melting when cooling of pipe stops. The data for ice build-up and melting for some regimes have been presented and analyzed. The data form the base for deriving semi-empirical correlations allowing to determine a time intervals necessary to generate of ice layers of a given thickness.
- ДокументVISCOSITY OF TERNARY SOLUTIONS COMPOSED OF PROPYLENE GLYCOL, ETHANOL AND WATER(2016) O. Ya. Khliyeva, A. S. Nikulina, M. P. Polyuganich, S. S. Ryabikin, V. P. ZheleznyThis paper presents the experimental data on the kinematic viscosity of water / ethanol / propylene glycol solutions that are prospective as coolants. An experimental setup with capillary viscometers was used to measure the kinematic viscosity of samples in the temperature range from 243K to 303K and in the wide range of mass fractions of components. Experimental uncertainty of the obtained experimental data does not exceed 0.4 %. Solutions compositions were chosen according to needs of the refrigeration industry in order to provide a possibility of their application at temperatures 233 K and higher. The new model for prediction of the kinematic viscosity of coolants within wide interval of reduced temperatures 0.1 ≤ ≤ 0.6 ( is the pseudocritical temperature) based on the limited experimental data both for pure substances and aqueous solutions of mono- and polyalcohols is presented in paper.
- ДокументMATHEMATICAL MODEL FOR THE STUDY AND DESIGN OF A ROTARY-VANE GAS REFRIGERATION MACHINE(2016) V. V. Trandafilov, M. G. Khmelniuk, O. Y. YakovlevaThis paper presents a mathematical model of calculating the main parameters the operating cycle, rotary-vane gas refrigerating machine that affect installation, machine control and working processes occurring in it at the specified criteria. A procedure and a graphical method for the rotary-vane gas refrigerating machine (RVGRM) are proposed. A parametric study of the main geometric variables and temperature variables on the thermal behavior of the system is analyzed. The model considers polytrope index for the compression and expansion in the chamber. Graphs of the pressure and temperature in the chamber of the angle of rotation of the output shaft are received. The possibility of inclusion in the cycle regenerative heat exchanger is appreciated. The change of the coefficient of performance machine after turning the cycle regenerative heat exchanger is analyzed. It is shown that the installation of a regenerator RVGRM cycle results in increased COP more than 30%. The simulation results show that the proposed model can be used to design and optimize gas refrigerator Stirling.