Modelling and optimisation of acoustic inertance segments for thermoacoustic devices

Abstract

Thermoacoustic devices may use high-amplitude sound waves to serve a variety of purposes such as cryogenics, domestic refrigeration, electricity generation or warning siren systems. In all designs, there is a transfer of acoustic power between the various 'sources' and 'sinks', especially at very high acoustic pressure levels (170dB+) and velocity amplitudes (which are significant fractions of the local Mach number). Inertance segments, in which the oscillatory flow is accelerated, represent a design challenge in balancing frictional or viscous losses with improvements to the compactness, weight and performance of the overall system. This paper considers optimisation of an inertance segment used in a standing-wave type heat-driven thermoacoustic device and compares experimental data with results obtained from numerical finite element modelling, acoustic transmission line theory and linear thermoacoustic formulations. Copyright © (2006) by the Australian Acoustical Society.