Triple Cycle: A Conceptual Arrangement of Multiple Cycle Toward Optimal Energy Conversion

Abstract

The purpose of this study is to find a maximum work output from various combinations of thermodynamic cycles from a viewpoint of the cycle systems. Three systems were discussed in this study: a fundamental combined cycle and two other cycles evolved from the fundamental dual combined cycle: series-type and parallel-type triple cycles. In each system, parametric studies were carried out in order to find optimal configurations of the cycle combinations based on the influences of tested parameters on the systems. The study shows that the series-type triple cycle exhibits no significant difference as compared with the combined cycle. On the other hand, the efficiency of the parallel-type triple cycle can be raised, especially in the application of recovering low-enthalpy-content waste heat. Therefore, by properly combining with a steam Rankine cycle, the organic Rankine cycle is expected to efficiently utilize residual yet available energy to an optimal extent. The present study has pointed out a conceptual design in multiple-cycle energy conversion systems.