TY - JOUR
T1 - Numerical study on the thermodynamic performance of a packed bed cryogenic energy storage system
AU - Tan, Hongbo
AU - Ding, Zhi
AU - Wen, Na
N1 - Publisher Copyright:
© 2022
PY - 2022/9
Y1 - 2022/9
N2 - Cold energy storage devices improve the round-trip efficiency of cryogenic energy storage systems, where a solid packed bed for cold energy storage (PBCES) is widely utilized. In this study, a three-dimensional transient porous media packed bed model was developed using computational fluid dynamics software ANSYS Fluent 2020 to study the thermodynamic characteristics of a solid PBCES system with cryogenic nitrogen as the working medium during the cold charging process. The effects of the superficial mass flow rate (Gin), inlet temperature of nitrogen, packing materials, porosity on the packed bed temperature distribution, pressure drop, cold storage efficiency (ηs), and cold exergy efficiency (ηEx) were investigated carefully. The results showed that the axial temperature distribution is a typical thermocline. The system performance is predominantly affected by the criterion of the complete charging (the minimum temperature difference between Face-2 and Face-1, ΔTF2-F1,min) and the Gin. The thermocline thickness decreased with a decrease in the Gin. The ηs and ηEx increased significantly with an increase in the ΔTF2-F1,min. The maximum ηs and ηEx were 77.69% and 75.21% at the Gin was 0.1 kg/(m2·s) when the ΔTF2-F1,min was 100 K. The change in porosity had a limited influence on the cryogenic storage performance but considerably influenced the pressure drop; Basalt was recommended as the optimal packing material in the present study. The superficial mass flow rate of working medium and the complete charging indicator (ΔTF2-F1,min) should be carefully determined to achieve high performance in a practical CES system. The developed simulation model would be promising and useful for the design and optimization of a practical packed bed for CES systems.
AB - Cold energy storage devices improve the round-trip efficiency of cryogenic energy storage systems, where a solid packed bed for cold energy storage (PBCES) is widely utilized. In this study, a three-dimensional transient porous media packed bed model was developed using computational fluid dynamics software ANSYS Fluent 2020 to study the thermodynamic characteristics of a solid PBCES system with cryogenic nitrogen as the working medium during the cold charging process. The effects of the superficial mass flow rate (Gin), inlet temperature of nitrogen, packing materials, porosity on the packed bed temperature distribution, pressure drop, cold storage efficiency (ηs), and cold exergy efficiency (ηEx) were investigated carefully. The results showed that the axial temperature distribution is a typical thermocline. The system performance is predominantly affected by the criterion of the complete charging (the minimum temperature difference between Face-2 and Face-1, ΔTF2-F1,min) and the Gin. The thermocline thickness decreased with a decrease in the Gin. The ηs and ηEx increased significantly with an increase in the ΔTF2-F1,min. The maximum ηs and ηEx were 77.69% and 75.21% at the Gin was 0.1 kg/(m2·s) when the ΔTF2-F1,min was 100 K. The change in porosity had a limited influence on the cryogenic storage performance but considerably influenced the pressure drop; Basalt was recommended as the optimal packing material in the present study. The superficial mass flow rate of working medium and the complete charging indicator (ΔTF2-F1,min) should be carefully determined to achieve high performance in a practical CES system. The developed simulation model would be promising and useful for the design and optimization of a practical packed bed for CES systems.
KW - Cryogenic energy storage
KW - Exergy analysis
KW - Packed bed
KW - Porous media model
UR - https://www.scopus.com/pages/publications/85133590644
U2 - 10.1016/j.applthermaleng.2022.118903
DO - 10.1016/j.applthermaleng.2022.118903
M3 - 文章
AN - SCOPUS:85133590644
SN - 1359-4311
VL - 214
JO - Applied Thermal Engineering
JF - Applied Thermal Engineering
M1 - 118903
ER -