CAJ | 학술논문

润滑油的流动对制冷系统的性能和可靠性有重要影响。建立滚动转子式压缩系统实验台，观测和研究膨胀阀出口和蒸发器出口制冷剂／油混合物的两相流流型。结果发现：在蒸发器出口处混合物的流动表现为“油渍”蠕动、“油膜”线状流、“油膜”环状流和雾状湿蒸汽流等流型；在膨胀阀出口有液气分相流和泡气分相流等流型。在一定的运行工况下，压缩机正过热度越小，“油膜”流动速度越快，越利于压缩机回油；当压缩机排气温度等于冷凝温度时，高含油量的液体节流后形成泡状流，使得系统性能恶化甚至造成压缩机损坏。
윤활유적류동대제랭계통적성능화가고성유중요영향。건립곤동전자식압축계통실험태，관측화연구팽창벌출구화증발기출구제랭제／유혼합물적량상류류형。결과발현：재증발기출구처혼합물적류동표현위“유지”연동、“유막”선상류、“유막”배상류화무상습증기류등류형；재팽창벌출구유액기분상류화포기분상류등류형。재일정적운행공황하，압축궤정과열도월소，“유막”류동속도월쾌，월리우압축궤회유；당압축궤배기온도등우냉응온도시，고함유량적액체절류후형성포상류，사득계통성능악화심지조성압축궤손배。
The flow of lubricant oil is important for refrigeration performance and reliability.The rolling piston compression test stand was established,and the two-phase flow patterns of refrigerant/oil mixture at the exit of expansion valve and evaporator were investigated.The research showed that there are creeping oil spots,oil film string flow,oil film annular flow,and mist refrigerant flow at the outlet of the evaporator.There are the liquid-vapor flow and the forth-vapor flow at the outlet of the expansion valve.Under certain operating conditions,the smaller the positive suction superheat,the faster “oil film”flows and the easier the oil returns to the compressor.When the discharge temperature equals to the condensing temperature,the liquid refrigerant with high oil concentration will form forth flow after throttling with expansion valves, which makes the system performance worse and even damages the compressor.