How to select regenerative configurations of CO₂ transcritical Rankine cycle based on the temperature matching analysis

CO₂ transcritical Rankine cycle is regarded as a potential technology for internal combustion engines waste heat recovery, and its regenerative configurations present great prospect to increase the power output capacity. This paper proposed different regenerator layout configurations based on the temperature matching analysis, including low temperature regenerative transcritical Rankine cycle (LR-TRC), high temperature regenerative transcritical Rankine cycle (HR-TRC), dual regenerative transcritical Rankine cycle (DR-TRC) and split dual regenerative transcritical Rankine cycle (SR-TRC). Afterward, the thermodynamics, electricity production cost (EPC) and miniaturization performance are implemented. The results show that regenerative configurations have an effect on improving net power output and SR-TRC obtained optimal value of net power output. For the perspective of economic performance, the greatest value is obtained for HR-TRC among four regenerative configurations. As for the miniaturization performance, the total heat transfer area increment of LR-TRC is the lowest. The comparative analysis results offer guidance for selecting optimal regenerative configurations.