Abstract: Based on the modified Einstein refrigeration cycle, the model of bubble pump and the entire system was established.According to the theory of two phase flow of homogeneous flow, the performance of the bubble pump working under slug condition was calculated, and the maximum efficiency under the different system pressure was obtained.Substitute these values into system thermodynamic model, the influence of main system operating parameters on its performance under the system pressure of 3-5 bar was simulated using software EES.Results show that:the COP of Einstein refrigeration under low pressure is better; the influence of evaporation temperature is greater than the condensation under different pressure; the system performance exists a maximum as the generator temperature increase and lower pressure does good to better system performance and is convenient to make low grade heat source(356-390 K).Those research results provides reliable parameter selection principle for key operation parameters of Einstein refrigeration system and indicated the direction of the design and further optimization of the system components.

Key words: Einstein cycle, two-phase flow, thermodynamics, model, bubble pump, performance calculation

摘要： 基于改进的Einstein制冷循环系统，对气泡泵及整个制冷系统进行理论建模。根据两相流均相流理论，对工作在弹状流情况下的气泡泵进行性能计算，得到不同压力下气泡泵的最大提升效率。并将其代入系统热力学模型，利用EES软件模拟探究了压力在（3～5）×10⁵范围内变化时，系统的主要运行参数变化对性能的影响情况。结果表明，在系统压力较低（3×10⁵Pa）的情况下，制冷系统的COP有较为理想的数值；不同压力下蒸发温度对系统性能的影响远大于冷凝温度；随着发生温度的增加，系统性能存在一最大值，且压力越小系统的COP也越高，更有利于利用低品位热源（356～390 K）。研究结果为Einstein制冷系统关键运行参数的选择提供了可靠的参数选取原则及依据，为系统各部件的设计乃至进一步的改进优化指明方向。

关键词: Einstein循环, 两相流, 热力学, 模型, 气泡泵, 性能计算