风冷模块机组部分负荷性能的试验研究

Experimental Study on the Part Load Performance of Modular Air-cooled Heat Pump

风冷模块机组的部分负荷性能决定了机组的实际运行能效。本文对比实测了3种不同设计的60kW风冷模块机组在部分负荷工况的性能,总结了机组的部分负荷性能特性和提高风冷模块IPLV的方法。传统风冷模块采用独立双系统设计,部分负荷单系统运行,性能较差。采用并联压缩机的单系统方案在部分负荷工况以单压缩机运行,充分利用两器面积,部分负荷COP相比独立双系统设计提高14.1%~19.1%,IPLV提高14.3%。在此基础上降低冷凝器风机转速可有效降低部分负荷功率,进一步提升能效。不同部分负荷工况COP最多可提高5.0%~8.0%,IPLV提高3.6%。各工况最高COP对应的风机转速基本相近,与满负荷的转速比约为0.7:1。

The part load performance of modular air-cooled heat pump determines the actual operating energy efficiency.The part load performance of three different designs of 60 kW modular air-cooled heat pump was tested and compared. The part load performance and the methods to increase the IPLV were summarized.The traditional air-cooled module adopts independent dual system design,and only a single system is operating under part load conditions,therefore,its performance is poor.In the novel single system scheme with compressors in parallel operation,only a single compressor operates under part load conditions so as to make full use of the areas of the condenser and evaporator,and the part load COP was improved by 14.1%~19.1% and IPLV by 14.3% compared to the independent dual system design. In addition,it is found that the reduction of condenser fan speed can effectively reduce part load power and further improve the energy efficiency. The highest part load COP can be increased by 5.0%~8.0% and IPLV increased by 3.6% compared to the single system. The fan speeds corresponding to the highest COP under different part load conditions were close to each other,and the speed ratio was about 0.7:1.