室温温区自由活塞斯特林制冷机设计

Design of Free Piston Stirling Refrigerator at Room Temperature

自由活塞斯特林制冷机作为一种新型制冷技术,具有效率高、可靠性好、结构紧凑、环境友好等特点。目前,室温温区自由活塞斯特林制冷机存在回热器声功利用量少、出口声功大等问题,导致排出器反馈声功大、尺寸大,给加工工艺和实际应用带来困难。本文基于SAGE软件,对室温温区自由活塞斯特林制冷机的核心单元结构进行了设计。通过多级制冷流程,提高制冷的声功利用,同时探究排出器对制冷性能的影响,寻找减小排出器直径的有效方法。在以制冷系数为优化计算目标.限制排出器行程的前提下,得到了不同核心单元直径的三级自由活塞斯特林制冷机可实现的最小排出器尺寸。计算结果显示,总核心单元等效面积相近时,三级自由活塞斯特林制冷机的排出器面积可减小至单级的49%。即多级制冷机有效减小了排出器尺寸,推动自由活塞斯特林制冷机在室温温区的应用。

As a new type of refrigeration technology,free piston Stirling refrigerator shows the advantages of efficiency,reliability,compactness and environmental friendliness.To date,the free piston Stirling refrigerator at room temperature range has problems as low power utilization and large outlet acoustic work.As a result,the feedback acoustic work of the displacer and the refrigerator’s size are both large,which brings difficulties to the technology promotion and real application.In this paper,the core of free piston Stirling refrigerator at room temperature is designed using SAGE software.By adopting the multi-stage refrigerator process,the acoustic work utilization of refrigerator is improved,and the influence of the displacer on the refrigeration performance is explored to find an effective method to reduce the diameter of the displacer.On the premise that the performance coefficient is taken as the optimization calculation objective with a limited displacer displacement,the minimum displacer diameter of three-stage free piston Stirling refrigerators with different core diameters is obtained.The calculation results show that the area of the displacer of the three-stage free piston Stirling refrigerator can be reduced to 49%of that of the single-stage refrigerator when the total core equivalent area is similar.That is,the multi-stage refrigerator effectively reduces the size of the displacer and promotes the application of the free piston Stirling refrigerator at room temperature.