Study of the influence of the plate-fin heat exchanger pressure drop on the performance of liquid air energy storage

Abstract Liquid air energy storage is a very promising energy storage technology, which has the advantages of large capacity, long time, long life and no geographical restrictions. In order to improve the efficiency and economy of the liquid air energy storage system, the optimization design of the heat exchanger is the focus of the research, especially the low-temperature plate-fin heat exchanger employed in the process of air liquefaction. The key design parameters of the heat exchanger include heat transfer temperature difference and pressure drop. However, most of the current studies only focus on the heat transfer temperature difference of the heat exchanger. Reducing heat transfer temperature difference can improve the system efficiency, but significantly increase the cost of the heat exchanger. Therefore, this paper mainly studies the influence of the pressure drop of plate-fin heat exchanger on the system and economic performance. Thermodynamic analysis based on steady-state mathematical model was employed to evaluate the system efficiency. The results show that a moderate increase of pressure drop can significantly reduce the cost of the plate-fin heat exchanger, while the system efficiency decreases slightly.