Experimental Investigation on Regenerator Materials of Stirling-type Pulse-tube Refrigerator Working at 20K

Abstract

This paper will introduce our recent experimental results of cryogenic regenerator materials employed in Stirling-type one-stage pulse-tube refrigerator for the use at liquid hydrogen temperature. Thermal diffusion coefficient, according to which we choose the suitable regenerator materials, will prove to be a useful reference. We will also discuss the impact of resistance of sphere regenerator materials on the performance of the refrigerator and the method to improve it. Take an overall consideration, suitable-size Er 3 Ni will be applied as the regenerator materials at the cold head and we achieve a remarkable 14.7 K no-load temperature.

Development of a high-frequency coaxial multi-bypass pulse tube refrigerator below 14K

“…Spheres regenerator possesses a larger flow resistance for its low porosity; the situation gets even worse at high frequency. Therefore, the optimum operating frequency for Er 3 Ni spheres regenerator is 30 Hz, which is lower than that for SSWM (35 Hz) [5]. After adjusting the MBFR, the no-load temperature can reach 13.9 K using Er 3 Ni spheres regenerator when the hot end was kept at 280 K.…”

“…Here two special cases are presented in Table 3. One case is that regenerator III was filled with Er 3 Ni with a diameter of 0.055-0.07 mm and 8.5 mm length [5].…”

“…In a previous study, we found Er 3 Ni is superior to lead and HoCu 2 in a refrigerator of the same type and has the potential to replace SSWM as the regenerator matrix material [5]. Table 1 shows some parameters of the regenerators.…”

Experimental study of the influence of cold heat exchanger geometry on the performance of a co-axial pulse tube cooler

“…In comparison with the traditional regenerative coolers such as G-M and Stirling coolers, the pulse tube cooler with no moving parts in low temperature region has the advantages of simple structure, high reliability, low mechanical vibration and low cost [1]. In retrospect, the quick development of Stirling type pulse tube coolers in the past two decades mainly benefited from the improvements of phase shifters [2][3][4] and regenerators [5][6][7]. On the other hand, the heat exchangers are also important.…”