| Title |
Development of a 1D Model and Performance Analysis at Extremely Low Temperature of an R290 Indirect Heat pump System with Vapor-Injection |
| Authors |
Yun Gu Heo ; Seung Hyun Jegal ; Sung Chul Kim |
| DOI |
https://doi.org/10.6110/KJACR.2026.38.8.426 |
| Keywords |
전기 자동차; 간접 히트펌프; 과불화화합물; 프로판; 증기 분사 Electric vehicle; IDS-HP; Indirect heat pump; PFAS; R29; Vapor-Injection |
| Abstract |
Propane (R290) is a promising alternative refrigerant for electric vehicle (EV) heat pumps, particularly with tightening regulations on PFAS. This study developed a 1-D GT-SUITE model of an R290-based indirect heat pump system (IDS-HP) to investigate the effect of vapor-injection (VI) at equivalent compressor discharge mass flow rates. The non-VI baseline model was calibrated and validated against experimental data across an ambient temperature range of -20 to 7°C. This validated baseline was then extended to a conceptual VI configuration for performance analysis from -35 to 7°C. In the VI cycle, an economizer was used to further subcool the liquid line and inject intermediate-pressure vapor between two series-connected compressors. Compared to the non-VI system, the VI system increased heating capacity by 7.2% to 9.0%, with only a limited increase in compressor power (1.2% to 2.0%). Consequently, the Coefficient of Performance (COP) improved across the entire operating range, showing a maximum increase of 7.49% between -30 and -25°C and a 5.88% increase at -35°C. Relative to an IDS-R1234yf system, the VI-enhanced R290 IDS-HP system demonstrated an 83.6% higher heating capacity and 16.2% higher COP at -35°C. These performance advantages also resulted in a 4.2% improvement in driving range at -20°C, suggesting that the VI-enhanced R290 IDS-HP system is a promising solution for EV cabin heating in extremely cold climates. |