Thermodynamic analysis of different two-stage transcritical carbon dioxide cycles

Performance optimization of transcritical CO2 cycle with parallel compression economization

“…However, in case of twostage compression transcritical CO 2 cycle, the intermediate pressure is also an influential parameter to decide the best COP along with the gas cooler pressure [6,11]. It makes necessary to optimize the gas cooler pressure and intermediate pressure simultaneously.…”

“…A significant amount of research has been carried out to improve the COP of transcritical CO 2 systems by cycle modification such as employing internal heat exchanger, multistage compression, expansion turbine, vortex tube and ejector expansion device [5]. Cecchinato et al [6] carried out thermodynamic analysis on twostage transcritical CO 2 cycles. It is shown that employing double compression with intercooling improves the performance significantly and also governs the choice of optimum intermediate pressure.…”

Transcritical carbon dioxide small commercial cooling applications analysis

“…Nevertheless today CO 2 is gaining more and more favour thanks to its very low environmental impact. In 1994 the Norwegian professor Gustav Lorentzen (2000) first proposed again this refrigerant as a working fluid for vapour compression inverse cycles and from that moment many other authors have extensively studied such applications, but the contributions of Cavallini and Nekså (2001), Nekså (2002), Groll (2001), Cecchinato et al (2009) and Kim et al (2004) appear to deserve a mention within the scope of the present paper. In general terms an inverse CO 2 operated cycle is very different from a traditional one since the high pressure is often supercritical and the resulting refrigerating cycle does not entail condensation, but a simple cooling process of dense fluid accomplished in the so-called 'gas cooler'.…”

Numerical analysis of transcritical carbon dioxide compression cycle: a case study

“…This means that even with the use of low-capacity systems, a lot of heat is wasted by the cycle. Cecchinato et al [2] conducted a thermodynamic and optimal assessment of a two-stage carbon dioxide transcritical cycle. In this study, several different cycles including a cycle with one stage compression, a cycle with two stage compression associated with a gas cooling circuit were analyzed.…”