| Title |
Solubility Consideration in Performance Analysis of a CO2 Twin Rotary Compressor |
| Authors |
김우영(Woo Young Kim) ; 안종민(Jong Min Ahn) ; 김현진(Hyun Jin Kim) ; 조성욱(Sung Oug Cho) |
| Keywords |
용해도 ; 이산화탄소/PAG ; 2단 압축 트윈 로타리 압축기 ; 누설유량 ; 압축기 성능 Solubility ; CO2/PAG ; Two-stage twin rotary compressor ; Leakge flow rate ; Compressor performance |
| Abstract |
For a CO2 two-stage twin rotary compressor used for heat pump water heater system, changes of CO2 solubility in PAG oil were investigated along the gas passages from the first stage suction to final discharge. Only slight changes in solubility took place in suction chambers for both of the first and second stages, but for compression chambers, solubility variation ranged from 0.115 to 0.136, and from 0.133 to 0.182, respectively for the first and second stages. Calculation of gas flashing in parts of leakage oil flows and of oil contained in control volumes due to solubility changes was conducted and included in gas pressure calculation. For the second stage, gas flashing amounts to around 5%～6% for most leakage flows. Cooling capacity, compressor input, and COP obtained by calculation were well compared to the experimental results. Effects of operation speed on the compressor per-formance was also studied:as the shaft speed increased, adiabatic efficiency decreased rapidly due to increased over-compression loss. |