Traditional thermoacoustic engines using conduction-driven, sensible heat transfer are unable to utilize low-grade thermal energy efficiently. Recently, it has been demonstrated that a phase-change thermoacoustic engine can initiate oscillations at a very low temperature difference; however, the steady-stage performance has yet to be extensively studied. In this work, a phase-change thermoacoustic engine with a looped resonator was simulated, based on a linear phase-change thermoacoustic theory. A binary gas mixture consisting of an inert gas and a condensable component was adopted as the working fluid. We numerically investigated the distributions of pressure, volumetric velocity, and acoustic power in the system. We also examined the steady-state performance (characterized by the pressure amplitude, acoustic power, and thermal efficiency) of the system under different mean pressures and temperature differences. The results show that the phase-change thermoacoustic engine can be driven by very low temperature differences (< 50 K) much more efficiently than its dry equivalent (i.e., the same system but without the condensable component). The findings demonstrate the promising potential of generating acoustic power through low-grade heat recovery, which can then be converted into electricity and cooling.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.