【摘要】 在二级脉管制冷机的第二级脉管热端分别采取了双小孔、双向进气以及无气库等三种不同的形式进行了实验比较，得到的最低制冷温度分别为３３Ｋ，１５５Ｋ和１４８Ｋ。实验结果表明，第二小孔具有强化调相及加快降温速率的双重作用。更多还原

【Abstract】 Three types of a two stage pulse tube refrigerator named double orifice type,double inlet type and reservoirless type which were in the hot end of the second stage pulse tube were tested.The lowest temperature was 3 3K,15 5K and 14 8K,respectively.The experimental result showed that the second orifice in the double orifice type had the role of enhancing the phase shifting effect and reducing the cool down process.·更多还原