Bottoming organic Rankine cycle for a small scale gas turbine: A comparison of different solutions

摘要: Abstract Recently, several efforts have been devoted to the improvement of thermal efficiency small gas turbines, in order approach typical values internal combustion engines same range power. One possibility is represented by a combined cycle, obtained coupling turbine bottoming organic Rankine cycle (ORC). This paper deals with definition main features an ORC system aimed recover heat from 100 kWe commercial recuperator. After optimization thermodynamic cycles, involving comparison between six working fluids, different expanders are analyzed, aim detecting, if possible, best suited machine. First, single stage both radial and axial flow configuration, designed specifically for each considered fluid, particular investigating opportunity mounting expander directly on high-speed shaft turbine. Then, performances these dynamic machines compared those positive displacement expanders, such as scroll devices, obtainable HVAC compressor minor revisions, reciprocating ones, here newly designed.