Design and Fabrication of Two Stage Thermoacoustic Engine to Reduce the Onset Temperature

Abstract

About 60% of primary energy is treated as waste heat but the temperature of this heat is low (200-300 0C). Thermoacoustic engine convert heat energy into high amplitude sound waves, which is used to drive thermoacoustic refrigerator or pulse tube cryocoolers by replacing the mechanical piston such as compressors. The potential of thermoacoustic engine is high but because of heat loss the actual efficiency is not so high. The onset temperature difference, defined as the minimum temperature difference across the sides of the stack at which the dynamic pressure is generated. Lowering the critical onset temperature is a challenging task. The authors designed a multistage thermoacoustic engine which oscillates with relatively low critical onset temperature TH/TR. The influence of the position of honeycomb ceramics is also investigated in this study.