R417A喷气增焓热泵热水器低温环境下的变流量特性分析

主要研究了R417A在喷气增焓空气源热泵系统中的替代应用,重点分析了低温环境下R417A替代R22的可行性。在对带闪蒸器的涡旋式压缩机喷气增焓热泵系统的热力学分析基础上,通过试验测试确定了R22和R417A 2种制冷剂在系统中的最佳充注量,随后在热水器一次加热循环条件下改变电子膨胀阀的开度以实现对循环补气量和系统流量的调节,分析了R22和R417A 2种系统在标准工况(20、15℃)、冬季工况(7℃、6℃)及低温工况(-7℃、-8℃)下的制热量、COP、吸排气压力及补气压力等试验数据,得出结论:喷气增焓空气源热泵系统处于最佳状态时,Pm≈(PePc)1/2;环境温度越低,R417A替代R22的优势越明显,即R417A更适合在低温环境下替代R22。

Variable Flow Characteristic Analysis of R417A Enhanced Vapor Injection Heat Pump in Low Temperature

The paperresearched thesubstitutability of R417 A in vapor injection air source heat pump water heater system. Mainly analyzed thereplaceability of R147 A to R22 in low temperature condition. On the base of thermomechanical analysis ofvapor injection heat pump system with flash vessel,determined the optimal refrigerant charge of R22 and R417 A in vapor injection heat pump water heater system by experiment. Under the direct-heated heating conditions,by changing the opening of electronic expansion valve to regulate system refrigerant volume and find out the optimal opening of R22 and R417 A system under standard conditions( 20℃,15℃),winter conditions( 7℃,6℃) and low temperature conditions(-7℃,-8℃). The results show that: When Pm≈( PePc)1 /2,the system was on optimum state; The environment temperature is lower,the feasibility of R417 A instead of R22 more obvious.