Abstract: The single-stage vapor compression refrigeration cycle system with single refrigerant is the most sophisticated technology，but low efficiency at lower temperature zone （?40℃） limits its applications. The mixed throttle refrigerator is able to adapt to different temperature zones，especially deep hypothermia district . This paper introduced the principles and characteristics of azeotropic，near azeotropic and non-azeotropic mixture refrigerants. Previous studies found that azeotropic and near azeotropic mixture refrigerants are similar to the single working fluid. Single-stage compression chiller with multiple working fluids relies on non-azeotropic refrigerant’s characteristics to achieve deep cooling. The studies of a mixed refrigerants Linde cycle system’s（LHR）the development history and current situation were introduced. This paper also introduced the characteristics and selection principles of the lubricant in cryogenic systems which combining the mixed refrigerant Linde cycle system experiment. Improvement measures such as increasing air-cooled pre-cooler，regenerator foamed and optimized aspects of the system were proposed

Key words: mixtures, Linde cycle, refrigeration, throttling

摘要： 单工质单级蒸汽压缩式制冷循环是目前最成熟的制冷技术，但在低温温区（?40℃以下）具有一定局限性，而混合工质节流制冷技术能够适应不同温区，特别在深低温区极具研究价值。本文介绍了共沸、近共沸及非共沸混合物制冷剂的原理及特点。研究发现，共沸和近共沸混合工质制冷剂与单工质具有相似的性质；单级压缩混合工质制冷机依靠非共沸混合制冷剂的高度温变相变特性实现深度制冷。阐述了一种混合工质林德循环系统（LHR）的国内外发展历史和研究现状，指出LHR经历了开式循环、多级压缩闭式和单级压缩闭式循环3个发展阶段。最后结合混合工质林德循环系统实验，提出了增加风冷预冷器、回热器发泡保温等改进措施及研究优化重点，包括混合工质组分及最佳配比、热物性计算、换热器保温等方面的优化。

关键词: 混合物, 林德循环, 制冷, 节流