Thermoacoustics of solids: a pathway to solid state engines and refrigerators

TL;DR

This paper demonstrates the existence of thermoacoustic oscillations in solid media through theoretical and numerical analysis, opening new avenues for solid-state engines and refrigerators.

Contribution

It provides the first theoretical and numerical evidence of thermoacoustic instabilities in solids, extending the concept beyond fluid media.

Findings

Thermoacoustic oscillations can occur in solid materials.

Differences in physical mechanisms affect the triggering of oscillations.

Potential for developing solid-state thermoacoustic devices.

Abstract

Thermoacoustic oscillations have been one of the most exciting discoveries of the physics of fluids in the 19th century. Since its inception, scientists have formulated a comprehensive theoretical explanation of the basic phenomenon which has later found several practical applications to engineering devices. To-date, all studies have concentrated on the thermoacoustics of fluid media where this fascinating mechanism was exclusively believed to exist. Our study shows theoretical and numerical evidence of the existence of thermoacoustic instabilities in solid media. Although the underlying physical mechanism is analogous to its counterpart in fluids, the theoretical framework highlights relevant differences that have important implications on the ability to trigger and sustain the thermoacoustic response. This mechanism could pave the way to the development of highly robust and reliable solid-state thermoacoustic engines and refrigerators.