Development of a slug flow absorber working with ammonia–water mixture: part II—data reduction model for local heat and mass transfer characterization

Thermally driven ammonia/water Kalina cycles have shown some promise for improving the efficiency of electricity production from low temperature reservoirs (T < 200°C). However, there has been limited application of these systems to exploiting widely available, disperse, waste heat streams for smaller scale power production (∼ 1 kWe). Factors limiting increased deployment of these systems include large, costly heat exchangers, and concerns over safety of the working fluid. The use of mini and microchannel (D < 1 mm) heat exchangers has the potential to decrease system size and cost, while also reducing the working fluid inventory, enabling penetration of Kalina cycles into these new markets. To demonstrate this potential, a detailed heat exchanger model for a liquid-coupled microchannel ammonia/water condenser is developed. The heat exchanger is sized to provide the required heat transfer area for a 1 kWe Kalina system with a source and sink temperature of 150° and 20°C, respectively. An additional constraint on heat exchanger size is that the fluid pressure loss is maintained below some threshold value. A parametric analysis is conducted to assess the effect of different correlations/models for predicting the underlying heat and mass transfer and pressure drop of the ammonia/water mixture on the calculated heat exchanger area. The results show that accurately minimizing the size of the overall system is dependent upon validated zeotropic heat and mass transfer models at low mass fluxes and in small channels.

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Corrigendum: Numerical study of heat and mass transfer enhancement for bubble absorption process of ammonia-water mixture without and with nanofluids

Thermal Science ◽

10.2298/tsci190203033e ◽

2019 ◽

Vol 23 (1) ◽

pp. 416-416

Author(s):

E Editorial

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Chemical Engineering ◽

Numerical Study ◽

Water Mixture ◽

Absorption Process ◽

Transfer Enhancement ◽

Ammonia Water ◽

Mass Transfer Enhancement ◽

National School

NUMERICAL STUDY OF HEAT AND MASS TRANSFER ENHANCEMENT FOR BUBBLE ABSORPTION PROCESS OF AMMONIA-WATER MIXTURE WITHOUT AND WITH NANOFLUIDS by Mohamed Bechir BEN HAMIDA, Jalel BELGHAIEB, and Nejib HAJJI Research Unit of Energy and Environment, National School of Engineers of Gabes, University of Gabes, Gabes, Tunisia Original scientific paper https://doi.org/10.2298/TSCI170313229B published in the journal Thermal Science, Year 2018, No. 6B, Vol. 22, pp. 3107-3120 since due to mistake of the Editorial staff, affiliations have not been written correctly, and are the following: NUMERICAL STUDY OF HEAT AND MASS TRANSFER ENHANCEMENT FOR BUBBLE ABSORPTION PROCESS OF AMMONIA-WATER MIXTURE WITHOUT AND WITH NANOFLUIDS by Mohamed Bechir BEN HAMIDA1, Jalel BELGHAIEB2,3, and Nejib HAJJI2,3 1 College of Engineering, Chemical Engineering Department, Hail University, Hail City, Saudi Arabia 2National School of Engineers of Gabes (ENIG), Department of Process Engineering, University of Gabes, Tunisia 3Research Unit of Energy & Environment Ionized, National School of Engineers of Gabes (ENIG), University of Gabes, Tunisia. Link to the corrected article <a href="http://dx.doi.org/10.2298/TSCI170313229B">10.2298/TSCI170313229B</a>

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