Performance evaluation of free piston compressor coupling organic Rankine cycle under different operating conditions

Results show that when the heated working fluid is at 11.5 bar and 383 K, the system achieves better performances than other thermodynamic states, of which k is 601.1 mg/kJ and η is 44.3%. Based on the optimum thermodynamic state and the principle of obtaining the maximum k, the specific input power determined by ṁ (332 g/cycle) and Tcyl (1.2 s/cycle) can make the system achieve better performances, of which k is 648.9 mg/kJ and η is 42.8%. Performances prediction in the real system based on the simulation results has been evaluated in this paper for its intended application. Through calculation and rational analysis, the compressing ability of ORC-FPC in real-world can reach 9.04 L/s and its actual size can be increased based on the required compressing capability of the final application.