Abstract
A thermoacoustic engine is one of external combustion engines and has a very simple structure. Thus, the engine can be a waste heat recovery device with low cost. To drive the engine, the heat source temperature is needed to be higher than the critical value. Recently, it was found that the critical value decreases when two-phase fluid is added into the working gas of the engine. However, the output power of the engine with two-phase fluid has not been experimentally investigated. In this paper, we measure the Q value and output power of the engine with and without two-phase fluid. The result of measurement of the Q value shows that the two-phase fluid does not contribute to the thermal and viscous energy loss and increases the acoustic power production. Therefore, it is considered that the reason why the critical value is reduced is the enhancement of energy conversion. When the temperature difference was 125℃, the measured output power of the engine with two-phase fluid was 0.4 W and the engine without two-phase fluid was not able to generate an acoustic power.
