The critical external heat source conditions for subcritical ORC system based on thermo-economics

• Published in: Journal of mechanical science and technology Vol. 30; no. 8; pp. 3853 - 3860
• Main Authors: Xiao, Lan, Wu, Shuang-Ying, Li, Chun
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society of Mechanical Engineers 01.08.2016; Springer Nature B.V; 대한기계학회
• Subjects: Control; Critical temperature; Dynamical Systems; Economics; Engineering; Expansion; Fluids; Heat; Heat sources; Humidity; Industrial and Production Engineering; Mass flow rate; Mechanical Engineering; Thermodynamics; Vibration; Working fluids; Zeotropic mixtures; 기계공학; Critical heat source condition; Pure working fluid; Zeotropic mixture working fluid; Subcritical ORC; Thermo-economics
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-016-0749-6

Considering the thermodynamic and economic constraints simultaneously, the critical external heat source conditions available for sub-ORC systems with pure or zeotropic mixture working fluids are clarified. The critical external heat source conditions include the maximum allowed heat source temperature T gi,max , the minimum allowed heat source temperature T gi,min and the minimum allowed heat source mass flow rate m g,min . The results show that, no matter using pure working fluid or zeotropic mixture working fluid, the maximum allowed heat source temperature T gi,max increases linearly with the increasing of its critical temperature T cr . For the pure working fluid, the minimum allowed heat source temperature T gi,min is not sensitive to the variation of T cr . While, for the zeotropic mixture working fluid, the minimum allowed heat source temperature T gi,min firstly falls down, then rises up along with the increasing of T cr . An increase in mass flow rate of heat source causes enlarged range of heat source temperature available. And the minimum allowed heat source mass flow rate m g,min reduces sharply with the increase of heat source temperature.