Utilization of sound energy and waste heat with thermoacoustics, which is conversion phenomena between sound and heat energies, is focused on. A cascade of flat plates (parallel-plate stack) positioned in a cavity flow can drive the thermoacoustic heat flow and create a heat pump using aerodynamic sound. The effects of the stack position on a thermoacoustic heat pump were investigated using two stack aperture ratios through simulations of the coupled phenomena between fluid–acoustic interactions in the cavity flow and heat conduction in the stack. In a reverse way, by adding heat to a stack in a cavity flow, aeroacoustically generated tone can be increased, which can be used for the acoustic sources for flow control.

Demonstration of thermoacoustic engine
Sound generation from thermoacoustic engine (movie with sound)