可变内容积比螺杆式压缩机的性能分析

Performance analysis on variable internal volume ratio screw compressor

随着冷水机组、单元式空调机和水源热泵机组等产品的能效指标从名义工况EER或COP发展到IPLV或ICOP,机组的变容量或变工况性能主要取决于压缩机的变容量或变工况性能。固定内容积比的螺杆式压缩机如果在偏离设计工况下工作,效率下降,进而导致整个机组的性能下降。本文研究变内容积比螺杆式压缩机,内容积比可变化,使得压缩机内压比与外压比与工况相适应,可提升压缩机效率及机组性能。应用于冷水机组、水源热泵机组时,水源热泵机组在制冷工况时能效比可提高14.1%～35%,冷水机组的IPLV可提高7.2%左右。

With energy efficiency index of water chillers,unitary air-conditioners and water source heat pump products has developed from the EER or COP of the nominal operating conditions to IPLV or ICOP of partial load conditions,variable capacity and working condition performance of unit depend on performance of compressor primarily.If fixed internal volume ratio screw compressors work in the deviation from the design conditions,the efficiency drops,then the performance of the entire unit decreases.Variable internal volume ratio screw compressor is studied.Because internal volume ratio of compressor is variable,external pressure ratio and internal pressure ratio can be compatible with the working conditions,efficiency and unit performance of compressor will be enhanced.There will be the significant energy-saving when the variable internal volume ratio screw compressors are applied into water chillers or water source heat pump,and the energy efficiency of water source heat pump can be increased by 14.1%～35% at cooling conditions,the IPLV of the chillers can be increased by about 7.2%.