Screening of pure fluids as alternative refrigerants

Saleh, B.; Wendland, Martin

doi:10.1016/j.ijrefrig.2005.05.009

Cited by 52 publications

(51 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…An alternative is the BACKONE equation [6][7][8][9][10][11][12][13][14]. Strictly speaking, BACKONE is a family of physically based EOS [6], which is able to describe thermodynamic properties of nonpolar, dipolar and quadrupolar fluids with good to excellent accuracy.…”

Section: The Backone Equation Of Statementioning

confidence: 99%

See 1 more Smart Citation

Working fluids for low-temperature organic Rankine cycles

Saleh¹,

KOGLBAUER²,

Wendland³

et al. 2007

Energy

961

386

View full text Add to dashboard Cite

A thermodynamic screening of 31 pure component working fluids for organic Rankine cycles (ORC) is given using BACKONE equation of state. The fluids are alkanes, fluorinated alkanes, ethers and fluorinated ethers. The ORC cycles operate between 100 and 30 1C typical for geothermal power plants at pressures mostly limited to 20 bar, but in some cases supercritical pressures are also considered. Thermal efficiencies Z th are presented for cycles of different types. In case of subcritical pressure processes one has to distinguish (1) whether the shape of the saturated vapour line in the T,s-diagram is bell-shaped or overhanging, and (2) whether the vapour entering the turbine is saturated or superheated. Moreover, in case that the vapour leaving the turbine is superheated, an internal heat exchanger (IHE) may be used. The highest Z th -values are obtained for the high boiling substances with overhanging saturated vapour line in subcritical processes with an IHE, e.g., for n-butane Z th ¼ 0.130. On the other hand, a pinch analysis for the heat transfer from the heat carrier with maximum temperature of 120 1C to the working fluid shows that the largest amount of heat can be transferred to a supercritical fluid and the least to a high-boiling subcritical fluid. r

show abstract

Section: The Backone Equation Of Statementioning

confidence: 99%

“…In order to calculate the thermodynamic properties and in particular the thermal efficiency, a fundamental equation of state is required. Here BACKONE equation of state is used [6][7][8][9][10][11][12][13][14]. This equation is shortly reviewed in Section 3 and parameters are given there for 31 pure component working fluids.…”

Section: Introductionmentioning

confidence: 99%

Working fluids for low-temperature organic Rankine cycles

Saleh¹,

KOGLBAUER²,

Wendland³

et al. 2007

Energy

961

386

View full text Add to dashboard Cite

show abstract

“…Deviations of "experimental" values of COP [8] from calculated by means of the trained artificial neural network are within the error of calculations via the multi-constant equations of state [10] - [12]. Appreciable deviations of a relative error (more than 5 %) are observed for low COP values that have no principal meaning because we are interested by the working fluids with the maximal power efficiency.…”

Section: World Renewable Energy Congress 2011 -Sweden 8-13 May 2011 mentioning

confidence: 99%

Sustainable Working Media Selection for Renewable Energy Technologies

Mazur

Nikitin

2011

Linköping Electronic Conference Proceedings

View full text Add to dashboard Cite

Abstract:The sustainable working media selection is one of the most important stages in renewable energy technologies. The compromise among such properties as contribution to greenhouse effect, flammability, toxicity, thermodynamic behaviour, performance specifications, and the others defines a sustainable decision. The aim of present work is to apply a fuzzy set methodology providing sustainability among thermodynamic, economic, and environmental requirements. The organic Rankine cycle (ORC) for the class of working fluids based on the hydrofluoroethers (HFE) is considered to demonstrate a proposed approach. To select new working fluids, which have no information on thermodynamic behavior, artificial neural networks (ANN) approach is offered to forecast the ORC energy efficiency. The ANN correlations for coefficient of performance (COP) and pressure ratio (output) as functions of critical temperature, critical pressure and normal boiling temperature (input) are built via REFPROP database. The validation set has been used to estimate the ORC energy efficiency without of thermodynamic property calculations. The accuracy of ANN prediction for the cycle performances does not exceed 4% relative to the training set values. The Bellman -Zadeh model as the intersection of membership functions (fuzzy criteria mappings) is applied to sustainable selection of working media.

show abstract

“…The natural refrigerants are the naturally occurring substances, namely, ammonia, hydrocarbons, carbon dioxide, water, air, etc. These natural refrigerants have zero ozone depletion potential, and the majority of them have zero GWP too, however, some of them can be ammable and/or toxic [1][2][3]. Since carbon dioxide is a constituent of the atmosphere, it would be obtained from atmospheric air by fractionation and would have no additional impact on global warming, except for the energy consumption associated with the fractionation process; the working fluid carbon dioxide can also contribute to an increase of energy consumption to the indirect emissions of the power plant that supplies electricity to the refrigerator.…”

Section: Introductionmentioning

confidence: 99%

Transcritical CO₂refrigerator and sub-critical R134a refrigerator: A comparison of the experimental results

Aprea

Maiorino

2009

Int. J. Energy Res.

View full text Add to dashboard Cite

SUMMARYThis paper describes experiments comparing a commercial available R134a refrigeration plant subjected to a cold store and a prototype R744 (carbon dioxide) system working as a classical 'split-systems' to cool air in residential applications in a transcritical cycle. Both plants are able to develope a refrigeration power equal to 3000 W. The R744 system utilizes aluminium heat exchangers, a semi-hermetic compressor, a back-pressure valve and a thermostatic expansion valve. The R134a refrigeration plant operates using a semi-hermetic reciprocating compressor, an air condenser followed by a liquid receiver, a manifold with two expansion valves, a thermostatic one and a manual one mounted in parallel, and an air cooling evaporator inside the cold store. System performances are compared for two evaporation temperatures varying the temperature of the external air running over the gas-cooler and over the condenser. The refrigeration load in the cold store is simulated by means of some electrical resistances, whereas the air evaporator of the R744 plant is placed in a very large ambient. The results of the comparison are discussed in terms of temperature of the refrigerants at the compressor discharge line, of refrigerants mass flow rate and of coefficient of performance (COP). The performances measured in terms of COPs show a decrease with respect to the R134a plant working at the same external and internal conditions. Further improvements regarding the components of the cycle are necessary to use in a large-scale 'split-systems' working with the carbon dioxide.

show abstract

Screening of pure fluids as alternative refrigerants

Cited by 52 publications

References 30 publications

Working fluids for low-temperature organic Rankine cycles

Working fluids for low-temperature organic Rankine cycles

Sustainable Working Media Selection for Renewable Energy Technologies

Transcritical CO₂refrigerator and sub-critical R134a refrigerator: A comparison of the experimental results

Contact Info

Product

Resources

About

Screening of pure fluids as alternative refrigerants

Cited by 52 publications

References 30 publications

Working fluids for low-temperature organic Rankine cycles

Working fluids for low-temperature organic Rankine cycles

Sustainable Working Media Selection for Renewable Energy Technologies

Transcritical CO2refrigerator and sub-critical R134a refrigerator: A comparison of the experimental results

Contact Info

Product

Resources

About

Transcritical CO₂refrigerator and sub-critical R134a refrigerator: A comparison of the experimental results