Contributions on Closed System Transformations Based Thermal Cycles

The research work is focused on novel feasible structures of non condensing mode trilateral thermal cycles which differs from the recently known trilateral thermal cycles in that the conversion of heat to mechanical work is performed undergoing closed process transformations along with the three state point changes of the cycle. The proposed cycle is characterised by the fact that in its active process, as heat energy is being absorbed under increasing specific volume, entropy and temperature undergoing a load-dependent path function, mechanical work is simultaneously performed, contrary to what happens in conventional Carnot based engines. An analysis of the proposed cycle is carried out and results compared with that of a Carnot cycle operating under the same ratio of temperatures. Into the range of relative low operating temperatures (320 K) high thermal efficiency is achieved reaching 25.4% for hydrogen, 36.3% for helium and 31.8% for argon as working fluids when compared with Carnot Factor (7.8%).