Modeling and thermodynamic analysis of a novel combined cooling and power system composed of alkali metal thermal electric converter and looped multistage thermoacoustically-driven refrigerator

A large amount of high-quality heat from alkali metal thermal electric converter (AMTEC) is wasted, which greatly degrades its thermodynamic performance and causes serious thermal pollution. For solving this issue, a novel combined cooling and power (CCP) distributed system including two static energy conversion units, i.e., the AMTEC unit and looped multistage thermoacoustic-driven refrigerator (LMTADR) unit, is proposed. The general performance for the proposed system is analyzed via establishing the mathematical model, and the optimal region is obtained by considering both equivalent power density and exergy efficiency. Then, the parameter sensitive analysis is represented to provide some theoretical guidance for design of the proposed system. The results reveal that compared with a sole AMTEC system, the maximum equivalent power density and exergy efficiency of the combined system are improved by 42.4% and 22.5%, respectively. When the performance improvement rate reaches the maximum, the combined system achieves an equivalent power density of 9203.3 W m⁻², a cooling rate density of 3190.2 W m⁻² and an exergy efficiency of 25.8%. This study not only proves the superiority of AMTEC-LMTADR combined system, but also implies the extensive possibility of recovering medium and high-grade heat through LMTADR for refrigeration.