Investigation on the cycle performance and the combustion characteristic of two CO2-based binary mixtures for the transcritical power cycle

Lisheng Pan, Yuejing Ma, Teng Li, Huixin Li, Bing Li and Xiaolin Wei

Energy, 2019, vol. 179, issue C, 454-463

Abstract: It is difficult to condense subcritical CO2 in the CO2 transcritical power cycle by the conventional cooling, because of CO2's low critical temperature. With the aim to solve this problem, a new transcritical power cycle is proposed, using a CO2-based binary mixture as working fluid. Two mixtures are considered, namely, n-butane/CO2 and isobutane/CO2. Because n-butane and isobutane are flammable, the flammability of the mixtures are worth of note as well as their cycle performance. A laminar flame combustion rate experimental platform is established to investigate the combustion characteristics of both mixtures under different mixing ratio. The results show that their critical temperature increases with increasing the organic fraction and their critical pressure shows a peak value in considered conditions. The critical temperature can reach 40 °C with the organic fraction of 0.0711 for n-butane/CO2 and 0.0806 for isobutane/CO2. Under these mixing ratios, the transcritical power cycle can run by the conventional water cooling. The thermal efficiency reaches the highest value of 12.78% under the mole ratio of 0.28/0.72 for n-butane/CO2. Isobutane/CO2 gives the best condition under the mole ratio of 0.32/0.68, with the thermal efficiency reaching 12.97%. The flammable critical mole ratios for n-butane/CO2 and isobutane/CO2 are 0.04/0.96 and 0.09/0.91, respectively.

Keywords: CO2-Based mixtures; Transcritical power cycle; Waste heat recovery; Flammability (search for similar items in EconPapers)
Date: 2019
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (9)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544219308734
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:179:y:2019:i:c:p:454-463

DOI: 10.1016/j.energy.2019.05.010

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().