Abstract
A thermoacoustic Stirling Engine with a high efficiency needs both the traveling wave phase and high acoustic impedance. However, the acoustic impedance of a freely traveling plane wave is fixed at the ρδ, resulting in significant viscous energy losses due to high acoustic velocities. So we focus on a position in a resonance tube, where both a high acoustic impedance and a traveling wave phase are formed. We put a regenerator stacked with many screen meshes into this paticular position and externally imposed steep temperature gradients along the regenerator. We succeed in the amplification and attenuation of sound intensity depending on the sign of the temperature gradient.