Effect of porosity on the performance of PCHE with embedded PCM/EG under fluctuating temperature conditions

The supercritical CO2 Brayton cycle is widely utilized by various industries because of its compactness and efficiency. However, in the actual process, there are always temperature fluctuations that affect the normal operation of the whole supercritical CO2 Brayton cycle system, in order to weaken the temperature fluctuations without adding additional components, a new structure of PCHE with PCM embedded in PCHE was designed in this study. Fluent was used to simulate the working conditions and compare with the commonly used PCHE under the same working conditions. It was found that the structures with porosity of 0.8 to 0.9, the percentage reduction of temperature fluctuations on the hot side was 26.84 %, 26.78 % and 26.49 %, respectively, and the percentage reduction of temperature fluctuations on the cold side was 40.30 %, 40.81 % and 41.63 %, respectively, and the percentage reduction of heat exchange was 1.8 %, 1.9 % and 2.3 %, respectively.