Thermoacoustic instability in solid media

Abstract

The exploration of thermoacoustic oscillations can be traced back to the 19th century when Sondhauss (1850) performed an experimental investigation that marked the birth of modern thermoacoustic research. Since then, several practical applications of the basic thermoacoustic effect were explored and ultimately led to the design of engineering devices such as heat engines or refrigerators. This fascinating mechanism was believed to occur only in fluids while our study shows theoretical and numerical evidence of the existence of thermoacoustic oscillations also in solid media. Although this mechanism shares common aspects with the more familiar thermoacoustics of fluids, our analysis shows that the underlying physical mechanism presents some important and non-trivial differences with the traditional theory. The discovery and validation of this mechanism may lead to new ideas enabling the development of the next generation of ultra-compact and robust solid-state thermoacoustic devices for direct thermal-to-mechanical energy conversion, and vice versa.The exploration of thermoacoustic oscillations can be traced back to the 19th century when Sondhauss (1850) performed an experimental investigation that marked the birth of modern thermoacoustic research. Since then, several practical applications of the basic thermoacoustic effect were explored and ultimately led to the design of engineering devices such as heat engines or refrigerators. This fascinating mechanism was believed to occur only in fluids while our study shows theoretical and numerical evidence of the existence of thermoacoustic oscillations also in solid media. Although this mechanism shares common aspects with the more familiar thermoacoustics of fluids, our analysis shows that the underlying physical mechanism presents some important and non-trivial differences with the traditional theory. The discovery and validation of this mechanism may lead to new ideas enabling the development of the next generation of ultra-compact and robust solid-state thermoacoustic devices for direct thermal-to-m...