熱音響冷凍機 Ｇ‐Ｍ型パルス管冷凍機の仕事損失分布

Abstract

This paper describes a simplified loss evaluation method for pulse tube coolers. Assuming an isotherm model, the workflow balance of the pulse tube cooler will be discussed in comparison with an experimental result. The work flow through the valves as well as the equivalent PV work are calculated to figure out the optimum operating condition for a given size of pulse tube. This method makes it easy to determine the basic size of each component and the input power for the required cooling capacity. Work losses of a pulse tube cooler driven by a valved compressor with different phase-shift mechanisms such as double-inlet, four-valve and active-buffer types are discussed. Loss due to enthalpy flow through the regenerator is also taken into account. Results of example calculations indicate performance improvements of 10% and 20% by replacing the phase-shift mechanism from double-inlet method to four-valve and active-buffer methods, respectively. It also indicated that the work loss at the switching valve to the compressor for the double-inlet method and enthalpy loss at the regenerator for the active-buffer method are the dominant losses.