| Title |
Thermo-Economic Performance Evaluation of a Supercritical CO2 Refrigeration System with an Internal Heat Exchanger Using Simulink |
| Authors |
Jung Hoon Yang ; Jin Kyun Cho ; Joo Hyun Moon |
| DOI |
https://doi.org/10.6110/KJACR.2025.37.11.521 |
| Keywords |
CO2 냉매 시스템; 내부 열교환기; 심스케이프; 시뮬링크; 과열도; 초임계 CO2 refrigeration system; Internal heat exchanger; Simscape; Simulink; Superheat; Transcritical |
| Abstract |
Global warming increases refrigeration demand, impacting electricity consumption as higher ambient temperatures degrade system performance (higher power, lower COP). We simulated a transcritical CO2 system, varying gas cooler tube diameter (0.004-0.011 m) and fin area (0.06-0.20 m²) from 20-40℃. Enlarging tube diameter (0.004 to 0.011 m) proved detrimental: at 40℃, COP decreased 21.2% (from 2.05 to 1.62) and total cost increased, indicating the optimal diameter is 0.004 m. Conversely, expanding fin area (0.06 to 0.20 m²) markedly improved heat rejection. At 40℃, COP increased 80% (from 1.22 to 2.19) and compressor power dropped 39% (from 148.1 to 90.4 W). While performance improved up to 0.20 m², total cost analysis identified an economic optimum in the 0.14-0.16 m² range. Comparative results demonstrate that fin area adjustments produce more significant performance changes than tube diameter modifications, particularly under high ambient temperature conditions. Therefore, in practical system design, it is more effective to address fin area configuration before tube diameter adjustments, as this approach can maintain higher energy efficiency over different seasons while also reducing operational costs. |