基于喷气增焓技术的轻型商用变频空气源热泵的研究

Study on light commercial frequency-conversion air source heat pump coupled with enhanced vapor injection technique

针对寒冷区域的供热需求,结合喷气增焓技术,研发一款在低环境温度下高制热能力输出的轻型商用变频空气源热泵。测试该系统在低环境温度工况下的性能,并与传统制热循环进行比较。测试结果表明,制热时喷气增焓系统存在最佳中间压力并实现制热时最大能力输出;在室外环境温度为-25~7℃时,喷气增焓系统比原系统在制热能力上均有较大的提高,有效拓展了系统的低温运行范围;在室外干/湿球温度-15℃/-16℃条件下,喷气增焓系统制热能力可达到系统额定制热能力的100%,在压缩机运行频率为100 Hz时,喷气增焓系统的COP可达到2.07,较对应工况下无补气系统COP提升10.5%;在室外环境温度为-20℃且压缩机运行频率为100 Hz时,喷气增焓系统COP较原系统提升6.2%;喷气增焓系统排气温度比原系统低,系统低频运行时排气温度差值较大。

According to the heating needs for cold regions,one light commercial frequency-conversion air source heat pump coupled with enhanced vapor injection technique is designed,and it has high heating capacity at low ambient temperature.The performance of the system under low ambient temperature condition is tested and compared with those of traditional heating cycle.The test results show that the enhanced vapor injection system could exhibit maximum heating output with the adjustment of optimal intermediate pressure.The heating capacity of the enhanced vapor injection system is improved greatly compared with that of the original system at outdoor ambient temperature of-25 ℃ to 7℃,which effectively expands the low-temperature operation scope of the system.The heating capacity of the enhanced vapor injection system at outdoor wet and dry bulb temperature of-15 ℃/16 ℃ could reach that of the rated condition to the fullest,and the COPcould reach 2.07 with the compressor frequency of 100 Hz,which is improved by10.5% compared with that of the system without enhanced vapor injection technique under the same condition.The COP of the enhanced vapor injection system with the compressor running frequency of 100 Hz at outdoor ambient temperature of-20 ℃ is increased by6.2% compared with that of the original system.The discharge temperature is lower than that of the original system,and the discharge temperature difference of the system under low frequency is larger.