Numerical study of flow and energy fields in thermoacoustic couples of non-zero thickness

A limitation in many previous numerical studies of thermoacoustic couples has been the use of stack plates which are of zero thickness. In this study, a system for modelling thermoacoustic couples of non-zero thickness is presented and implemented using a commercial CFD code. The effect of increased drive-ratio and plate thickness upon the time-average heat transfer through the stack material is investigated. Results indicate that the plate thickness strongly controls the generation of vortices outside the stack region, perturbing the flow structure and heat flux distribution at the extremities of the plate. An increase in plate thickness is also shown to improve the spatial integral of the total heat transfer rate but at the expense of increased entropy generation. (C) 2008 Elsevier Masson SAS. All rights reserved.