The thermoacoustic stack is considered to be the heart of standing wave thermoacoustic systems. The flow at the end of the stack plates is complex and is dominated by concentrated eddies at high drive ratios, which affect flow motion, heat transfer, and the performance of the thermoacoustic device. In this paper, the oscillatory flow in the thermoacoustic stack is studied numerically using a commercial CFD package FLUENT 6.1. In this work, the stack is modelled as a set of 2-D isothermal flat plates, with no heat exchangers. Two drive ratios are used: 0.3 and 1.0%. The numerical results are compared with the experimental data and predict the so-called vortex "leap-frogging" and vortex shedding phenomena. A very good agreement is found. This work is a step towards understanding and mapping out the behaviour of the flows induced by thermoacoustic effects, which is essential to reach the optimal performance of thermoacoustic devices.
|Title of host publication
|Proceedings of the 22nd IIR International Congress of Refrigeration (ICR 2007)
|Number of pages
|Published - 21 Aug 2007