This Letter unveils a novel observation of condensation shock in a thermoacoustic prime mover with a wet stack, powered by a consistent 70 W heat input and maintained at atmospheric pressure. Intermittent pressure bursts, triggered by distinct acoustic cycles, reveal new characteristics of non-combustion-driven thermoacoustic instabilities, expanding the horizon beyond the energy conversion applications of traditional heat engines. Our findings, highlighted by pressure bursts reaching up to 35.8 kPa and detailed through time–frequency analysis, not only emphasize the critical role of phase-change dynamics but also pave the way for potential applications in heat transfer and material separation.

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