Inertance Tube Optimization for kW-Class Pulse Tubes

Growing interest in larger scale pulse tubes has focused attention on optimizing their thermodynamic efficiency. For Stirling‐type pulse tubes, the performance is governed by the phase difference between the pressure and mass flow, a characteristic that can be conveniently adjusted through the use of inertance tubes. Unfortunately, data describing the optimized inertance geometry as a function of desired phase‐shifts and acoustic power are not readily available. In this paper we present measurements of pressure, mass flow, and phase shift for inertance tubes subjected to kW‐level acoustic power flows. This type of data can be used to characterize the optimal inertance geometry, length and diameter, for a desired phase shift and acoustic power. The measurements are compared to an inertance tube model based on transmission line theory.