Experimental Investigation and Thermoacoustic Analysis of a Single-Stage Pulse Tube Refrigerator with an Active Displacer

The Stirling-type pulse tube refrigerator is a widely used refrigerator that has been extensively applied in space. An optimal phase angle between the pressure wave and volume flow is essential for a pulse tube refrigerator. The active displacer installed at the hot end of a pulse tube can be used to actively control the phase angle and enable recovery of the expansion power at the warm end of the pulse tube, leading to high efficiency. The main parameters for a pulse tube refrigerator with an active displacer are the phase and displacement of the active displacer. This manuscript studies the impact of displacer phase and displacement on a 40 K single-stage pulse tube refrigerator with an active displacer by thermoacoustic analysis, which is helpful for studying the thermodynamic characteristics of such a refrigerator and provides a method for more effective design and computing. The effects on the pressure, acoustic power, and cooling capacity are investigated by analytically solving the thermoacoustic model. A pulse tube refrigerator developed in our laboratory is tested, and the experimental results are compared with the results of thermoacoustic analysis.