Results 1 to 10 of about 1,898 (161)
Thermal Energy Storage of R1234yf, R1234ze, R134a and R32/MOF-74 Nanofluids: A Molecular Simulation Study. [PDF]
Materials (Basel), 2018 Thermal energy storage can be carried out by working fluid adsorbing and desorbing in porous materials. In this paper, the energy storage properties of four refrigerants, R1234yf, R1234ze, R134a and R32, with M-metal organic framework (MOF)-74 (M = Zn ...
Hu J, Liu C, Liu L, Li Q.
europepmc +3 more sources
Experimental evaluation of system modifications to increase R1234ze(E) cooling capacity [PDF]
Applied Thermal Engineering, 2017 The GWP limitations are being progressively introduced in Europe through Regulation EU No 517/201, phasing out R134a in most of its refrigeration and air conditioning applications. Pure hydrofluoroolefins are proposed to substitute this fluid, however generally system modifications are needed to achieve a good performance.
Mota-Babiloni, Adrián +3 more
openaire +3 more sources
Condensation and Evaporation of R134a, R1234ze(E) and R1234ze(Z) Flow in Horizontal Microfin Tubes at Higher Temperature [PDF]
, 2014 Hydrofluoro-olefin R1234ze(E) and the isomer R1234ze(Z) are anticipated to be environment-friendly alternatives of R134a. Especially, R1234ze(Z) is most likely to be suitable for high-temperature heat pumps in industries. The heat transfer characteristics of those refrigerants R134a, R1234ze(E) and R1234ze(Z) are experimentally compared in this study ...
Kondou, Chieko +3 more
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Comparison between R134a and R1234ze(E) during Flow Boiling in Microfin Tubes [PDF]
Fluids, 2021 Environmental concerns are forcing the replacement of commonly used refrigerants, and finding new fluids is a top priority. Soon the R134a will be banned, and the hydro-fluoro-olefin (HFO) R1234ze(E) has been indicated as an alternative due to its smaller global warming potential (GWP) and shorter atmospheric lifetime.
Lucchini A. +4 more
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Condensation and evaporation of R32/R1234ze(E) and R744/R32/R1234ze(E) flow in horizontal microfin tubes, 2015 The heat transfer characteristics of the low global warming potential refrigerant mixture R744/R32/R1234ze(E) in a horizontal microfin tube were investigated in this study. The condensation heat transfer coefficient of R744 /R32/R1234ze(E) (9/29/62 mass %) is somewhat lower than that of other mixtures, e.g., R744/R32/R1234ze(E) (4/43/53 mass %) and R32/
Chieko Kondou +2 more
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Theoretical analysis of R1234ze(E), R152a, and R1234ze(E)/R152a mixtures as replacements of R134a in vapor compression system [PDF]
Advances in Mechanical Engineering, 2016 In this article, R1234ze(E), R152a, and three mixtures M1, M2, and M3 composed of R152a and R1234ze(E) (in the ratio of 60:40, 50:50, and 40:60, by mass, respectively) as drop-in replacements of R134a in vapor compression system were theoretically analyzed.
Zhaofeng Meng +3 more
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IET Renewable Power Generation, Volume 17, Issue 16, Page 3741-3754, 7 December 2023., 2023 Low global warming potential (GWP) fluids were used to investigate strategies for reducing the effects of global warming and performance compared with hydro fluoro carbons (HFC) fluids. Four different combinations of the sCO2 cycle and ORC, including basic recuperated, pre‐compression, recompression with main compressor intercooling, and partial ...
Yunis Khan, Hakan Caliskan, Hiki Hong
wiley +1 more source
Energy Science &Engineering, Volume 11, Issue 9, Page 3070-3081, September 2023., 2023 A cascade heat pump is used to absorb latent heat of steam condensation. After twice compressions, the temperature of the working fluid is sufficiently high to vaporize liquid water. The heat pump fully utilizes thermal energy instead of direct electric heating, saving 65% of power consumption. Abstract Waste heat recovery is common in high‐temperature
Zhicong Fang +3 more
wiley +1 more source
Energy Science &Engineering, Volume 11, Issue 9, Page 3289-3306, September 2023., 2023 In this work, pumped thermal energy storage systems based on a transcritical CO2 charging process are investigated. A two‐zone water storage tank with a storage temperature of 115°C is used as thermal energy storage. For discharge, an Organic Rankine Cycle and, alternatively, a transcritical CO2 heat engine are investigated.
Jonas Bodner +3 more
wiley +1 more source
Mixture Condensation of Ethanol/Water and Ethanol/Siloxane in a Vertical Double Pipe
Chemie Ingenieur Technik, Volume 95, Issue 5, Page 724-731, May 2023., 2023 Experimental data is presented for mixture and pure fluid condensation within a wide composition range. Influential parameters for the heat transfer deterioration of mixtures are discussed. The results enable an explicit calculation of condensation heat transfer coefficients depending on the mixture composition.
Conrad Zimmermann +3 more
wiley +1 more source