Results 151 to 160 of about 1,682,876 (216)

Evaluation of Zeotropic Refrigerant Mixtures R32/R134A in Flow Condensation

Advanced Energy Systems, 1997
Abstract Experiments on flow condensation have been conducted with pure R32, R134a and R32/R134a mixtures. The results have been represented in form of local and mean heat transfer coefficient, as well as pressure drop. The heat transfer data is compared with the prediction from correlations in literature. An analysis is also carried out
D. W. Shao, E. Granryd
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Condensation of ternary low GWP zeotropic mixtures inside channels

International Journal of Refrigeration, 2019
Abstract The condensation heat transfer coefficient and two-phase frictional pressure drop of ternary zeotropic mixtures R455A (R32, R1234yf and R744 at 21.5/75.5/3.0% by mass composition) and R452B (R32, R1234yf and R125 at 67.0/26.0/7.0% by mass composition) have been measured inside a minichannel (0.96 mm diameter) and a conventional tube (8.0 mm ...
Azzolin, Marco, Berto, Arianna, Bortolin, Stefano, Moro, Lorenzo, Col, Davide Del   +4 more
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Theoretical evaluation of performance of zeotropic mixtures in refrigerating cycles

1995
Zeotropic mixtures sometimes in the past have been proposed in order to improve the energy efficiency of refrigeration processes when a fluid need to be cooled in an extended tem¬perature range; moreover they offer also the possibility of a stepless and energy effective capacity modulation, by means of a change in the composition of the operating fluid,
S. Bobbo, R. Camporese, CORTELLA, Giovanni, FORNASIERI, Ezio   +3 more
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Simulation of Isothermal and Adiabatic Leak Processes of Zeotropic Refrigerant Mixtures

HVAC&R Research, 1995
Nonflammable zeotropic mixtures of flammable and nonflammable refrigerants are possible alternative refrigerants for use in domestic heat pumps and air conditioners. Refrigerant leakage from such a system is of paramount concern since it is possible that a mixture composition will shift to a flammable range.
M. S. Kim, D. A. Didion
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An air-conditioning unit with a zeotropic mixture controlled by a distillation column

Energy, 1998
Abstract We describe a new air-conditioning and heat-pump system, which may be used to separate a refrigerant mixture efficiently and adjust the composition in the system with cooling- or heating-load changes. A dynamic model has been developed to analyze the transient behavior of the capacity-control system.
YANG ZHAO, MA YITAI, ZHAO SANYUAN, LI YIE   +3 more
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Effect of mixture composition on the formation of pinch points in condensers and evaporators for zeotropic refrigerant mixtures

International Journal of Refrigeration, 1999
Abstract In a recent study, it was shown by the authors that perfect glide matching of heat transfer fluid and the refrigerant is difficult in condensers and evaporators for many zeotropic mixtures and also that pinch points can occur in both the condensers and evaporators due to the non-linear variation of enthalpy during phase change.
G Venkatarathnam, S Srinivasa Murthy
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Boiling heat transfer of new zeotropic mixtures

2019
The aim of the present work is to investigate the heat transfer performance of non-azeotropic ternary low global warming potential (GWP) mixtures when vaporizing inside two channels: a 8,0 mm inner diameter tube and a 0,96 mm inner diameter channel. The tested mixtures are R455A, which is a ternary blend of R32, R1234yf and R744 (21,5/75,5/3,0% by mass
Berto A., Guzzardi C., Azzolin M., Bortolin S., Del Col D.   +4 more
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Synthesis of partially thermally coupled distillation flowsheets: Zeotropic mixtures

Theoretical Foundations of Chemical Engineering, 2011
This article presents a detailed description of algorithms for generating the complete set of n-component zeotropic distillation flowsheets for sequences of simple two-section columns and for sequences including partially thermally coupled complexes. The description of the algorithms is oriented toward writing of implementing computer programs.
M. I. Skvortsova, A. V. Timoshenko, D. G. Rudakov   +2 more
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Distillation of Nonideal Ternary Zeotropic Mixtures in Two-Feed Columns

Theoretical Foundations of Chemical Engineering, 2002
The continuous distillation of ternary nonideal zeotropic mixtures in two-feed columns is modeled. The results obtained are compared with the results of continuous distillation in one-feed columns. The topography of the field of relative-volatility coefficients is considered for various types of zeotropic systems.
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STUDY OF ZEOTROPIC MIXTURES FOR COGENERATION IN THE CEMENT INDUSTRY

Procceedings of the 18th Brazilian Congress of Thermal Sciences and Engineering, 2020
Thais Assis, Felipe Raul Ponce Arrieta
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