Regenerator Operation at Very High Frequencies for Microcryocoolers
Regenerator Operation at Very High Frequencies for Microcryocoolers
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DOI：
10.1063/1.2202623
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发表时间：
2006-05
期刊：
影响因子：
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通讯作者：
R. Radebaugh;A. O'Gallagher
中科院分区：
文献类型：
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作者：
R. Radebaugh;A. O'Gallagher
斯特林和斯特林型脉管制冷机的尺寸由压力振荡器的尺寸决定。对于高于约60 K的冷端温度，这种低温冷却器通常以高达约60 Hz的频率操作。对于给定的功率输入，更高的工作频率将允许减小压力振荡器的尺寸和质量。然而，简单地增加操作频率导致再生器中的大损耗。这里导出的简单的分析方程显示了频率和压力的正确组合，沿着优化的再生器几何形状，可以导致在高达1 kHz的频率下成功的再生器操作。在这样高的频率下的有效再生器操作仅在约5至8MPa的压力和非常小的水力直径和长度下才是可能的。其他几何参数也必须针对这些条件进行优化。分析方程用于指导参数的正确组合。本文用REGEN3.2软件对优化后的再生器在60 Hz、400 Hz和1000 Hz三种频率下的运行情况进行了数值计算，结果表明，当平均压力为7 MPa，频率较高时，再生器在400 Hz和1000 Hz下的性能系数分别约为60 Hz时的78%和68%。与60 Hz操作的2.5 MPa相比。平行管的1000 Hz性能系数与60 Hz时的屏几何形状的性能系数大致相同。与相同输入声功率的60 Hz情况相比，1000 Hz时的压缩机和冷端扫掠体积减少了47倍，这可以使MEMS应用的微型制冷机的开发成为可能。
The size of Stirling and Stirling‐type pulse tube cryocoolers is dominated by the size of the pressure oscillator. Such cryocoolers typically operate at frequencies up to about 60 Hz for cold‐end temperatures above about 60 K. Higher operating frequencies would allow the size and mass of the pressure oscillator to be reduced for a given power input. However, simply increasing the operating frequency leads to large losses in the regenerator. The simple analytical equations derived here show how the right combination of frequency and pressure, along with optimized regenerator geometry, can lead to successful regenerator operation at frequencies up to 1 kHz. Efficient regenerator operation at such high frequencies is possible only with pressures of about 5 to 8 MPa and with very small hydraulic diameters and lengths. Other geometrical parameters must also be optimized for such conditions. The analytical equations are used to provide guidance to the right combination of parameters. We give example numerical calculations with REGEN3.2 in the paper for 60 Hz, 400 Hz, and 1000 Hz operation of optimized screen regenerators and show that the coefficient of performance at 400 Hz and 1000 Hz is about 78 % and 68 %, respectively, of that for 60 Hz when an average pressure of 7 MPa is used with the higher frequency, compared with 2.5 MPa for 60 Hz operation. The 1000 Hz coefficient of performance for parallel tubes is about the same as that of the screen geometry at 60 Hz. The compressor and cold‐end swept volumes are reduced by a factor of 47 at 1000 Hz, compared with the 60 Hz case for the same input acoustic power, which can enable the development of microcryocoolers for MEMS applications.