单缸补气转子式压缩机在热泵系统中制热性能

利用中间补气技术将单缸滚动转子式压缩机应用于空气源热泵系统中，系统地研究以R410A为冷媒的热泵系统在变频、变补气压力工况下制热性能的变化规律。实验结果表明：中间补气系统的制热量及系统功率均随着压缩机频率f、中间补气压力p_inj的增加呈上升趋势，同频率下系统功率则以线性方式增长，而系统制热量随着补气压力及频率的增大，其相对增长率逐渐减小。因此COP_h在低频时存在最佳补气压力，而在高频时无极值点；与单级压缩系统相比，在800~1200 kPa、50~80 Hz范围内，中间补气系统的制热量、功率、COP_h最大提升分别为27.55%、30.75%、7.1%。随着频率及补气压力的增加，系统COP_h下降，因此中间补气技术应与合理的控制策略相结合，可使中间补气系统达到节能高效的目的。

Heating performance of single cylinder vapor injection rotary compressor applying in air-source heat pump system

A novel single cylinder rotary compressor, which was increased a vapor injection hole near the discharge port, was adopted to improve the heating performance of a flash tank vapor injection air-source heat pump (FTHP) system at low ambient temperature. The effects of compressor frequency f and injection pressure p_inj on system performances of a R410A FTHP system were measured and investigated systematically. The results showed that both heating capacity and power consuming of the FTHP system increased with increasing the compressor frequency and injection pressure. The FTHP system power consuming at fixed frequency increased linearly with increasing injection pressure. The increasing rate of FTHP system heating capacity declined as the frequency and injection pressure increased. Therefore, the heating COP_h had a peak value at certain injection pressure when the frequency was low. After the peak point or at high frequency, the heating COP_h decreased as the frequency and injection pressure increased. In the range of 800 kPa to 1200 kPa and 50 Hz to 80 Hz, the maximum improvement of the FTHP heating capacity, power consuming, and COP_h were 27.55%, 30.75% and 7.1%, respectively, compared to the single stage compression system. In order to make the FTHP system efficiently, the control strategy must be optimized to keep the system operated at the optimum injection pressure and frequency.