Theoretical and experimental investigation of the dynamic behaviour of a standing-wave thermoacoustic engine with various boundary conditions

This paper investigates the dynamic behaviour of a one-dimensional, standing-wave thermoacoustic engine with various boundary conditions. The thermoacoustic engine is composed of an acoustic tube and a ceramic stack with two heat exchangers. The tube has one end open and the other end closed with a deformable plate whose boundaries are constrained. Theoretical models are developed based on the acoustic wave equations and the linear theory of thermoacoutics and validated by experiment. With the validated theoretical models, a parametric study is performed to investigate the influence of the boundary conditions at both ends of the tube. It is found that acoustic radiation at the open end and the presence of the deformable structure at the closed end not only influence the onset temperature and frequency of the system, but also affect the acoustic field along the tube. The developed theoretical models and experimental method in this study provide useful guidelines for the design of thermoacoustic engines for potential energy harvesting systems. (C) 2018 Elsevier Ltd. All rights reserved.