高转速离心式制冷压缩机设计及特性研究

Study on Design and Characterization of High-Speed Centrifugal Refrigerant Compressors

摘要: 制冷技术在当今社会的各个领域发挥着重要作用，如食品制冷、空调制冷等。制冷技术通常需要一定的制冷设备来实现，高速离心式制冷是一种典型的现代制冷设备。通过计算流体动力学模拟，比较了R-134a制冷剂到混合制冷剂R-513A和氢氟烯烃制冷剂R-1234yf在不同负荷下工作流体的性能和内部流场。利用美国国家标准与技术研究院(National Institute of Standards and Technology, NIST)数据库中的制冷剂特性，以及不同部分负荷下的压缩机速度和质量流速，使用单级280RT磁浮离心式制冷剂压缩机，预测了制冷剂更换前后的性能差异。压缩机的运行条件是基于同一制冷循环的冷凝和蒸发温度，与目标的制冷量相同，以比较不同制冷剂的性能差异。本研究采用计算流体力学(CFD)软件进行流场模拟，结果表明，离心式压缩机直接更换制冷剂后，R-1234yf叶轮的全负荷效率比R-134a下降了13.2%，R-513A全负荷效率下降了10.0%，而制冷剂的全负荷效及三种制冷剂的部分负荷效率差异小于全负荷效率。

Abstract: Refrigeration technology plays an important role in various fields of today’s society, such as food refrigeration, air conditioning refrigeration, etc. Refrigeration technology usually requires certain refrigeration equipment to implement, and high-speed centrifugal refrigeration is a typical modern refrigeration equipment. Computational fluid dynamics simulations were performed to compare the performance and internal flow fields of working fluids from R-134a refrigerant to mixed refrigerant R-513A and hydrofluoroolefin refrigerant (HFO) R-1234yf at different loads. The dif-ference in performance before and after refrigerant replacement was predicted using refrigerant properties from the National Institute of Standards and Technology (NIST) database, as well as compressor speed and mass flow rate at different partial loads, using a single-stage 280RT magnetic float centrifugal refrigerant compressor. The compressor operating conditions were based on the condensing and evaporating temperatures of the same refrigeration cycle, with the same cooling capacity as the target, to compare the performance differences of different refrigerants. In this study, computational fluid dynamics (CFD) software was used for flow field simulation, and the results showed that after direct refrigerant replacement of the centrifugal refrigerant compressor, the full-load efficiency of R-1234yf impeller decreased by 13.5% and R-513A full-load efficiency decreased by 10.0% compared to R-134a, while the differences of full-load efficiency of refrigerants and part-load efficiency of the three refrigerants were smaller than the full-load efficiency.