Experimental study of a 1 kw organic Rankine cycle with a zeotropic mixture of R245fa/R134a. (15th December 2015)

• Record Type: Journal Article
• Authors: Bamorovat Abadi, Gholamreza; Yun, Eunkoo; Kim, Kyung Chun
• Is Part Of: Energy. Volume 93:Part 2(2015)
• Page Start: 2363
• Page End: 2373
• Publication Date: 2015-12-15
• Subjects: Organic Rankine cycle -- Zeotropic mixtures -- R245fa -- R134a -- Composition shift; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2015.10.092
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: The performance of a new zeotropic mixture of R245fa 60%/R134a 40% (molar concentration) in small scale ORC (organic Rankine cycle) was proposed and evaluated experimentally. For a range of heat source temperatures, the power output and thermal efficiency of the ORC system with this mixture was analyzed. The experimental data is presented for a 1 kW scroll expander and a heat source temperature between 80 and 120 °C. The results showed that the proposed zeotropic mixture increases the power output compared to an identical ORC with pure R245fa despite working at a lower pressure ratio. With increasing heat source temperature, the pure R245fa ORC becomes increasingly vigorous. Therefore, the best application of this mixture would be in heat sources with temperatures between 80 °C and 100 °C, where the pure R245fa ORC cannot have a high expander inlet pressure; hence, it works at lower pressure ratios. Highlights: Experiment data for ORC with zeotropic mixture of R245fa 60%–R134a 40% is presented. The performance of pure R245fa was compared to that of ORC with the mixture. The ORC with mixture of refrigerants as working fluid generated higher net power. The ORC with mixture has lower pressure ratio and higher condensing pressure. Pure R245fa ORC has better thermal efficiency.