| Title |
Performance Analysis of Scroll Expander-Compressor Unitfor CO2 Transcritical Cycles |
| Keywords |
Expander-compressor ; 팽창기-압축기 ; COP ; 성적계수 ; Efficiency ; 효율 ; CO2 trans-critical cycle ; CO2 초임계 사이클 |
| Abstract |
In a two-stage compression CO2 transcritical cycle, application of a scroll ex-pander-compressor unit has been considered in order to improve the cycle COP. For both ex-pander and 1st stage compressor, scroll wrap profile which was originally designed for a R410A air-conditioning cycle mechanism was used with minor modifications: wrap height and involute end angle were adjusted for required displacement volume and built-in volume ratio. For pressure condition of 10MPa/3.5MPa and expander inlet temperature of 35℃, 25% im-provement in COP was obtained by using expander-compressor unit. As evaporator pressure increased, COP improvement was lowered mainly due to decreasing compressor performance. |