DESIGN AND CONSTRUCTION OF A FOUR-STAGE TRAVELLING-WAVE THERMOACOUSTIC SYSTEM FOR POWER GENERATION

This work describes the design and construction of a fourstage traveling-wave thermo-acoustic system for electricity generation. The thermo-acoustic conversion consists of using a sound-wave for the transfer of heat from a low to hightemperature medium or the use of heat energy to generate a sound wave. Both the absence of moving parts and the simplicity of thermo-acoustic systems make the technology sustainable for converting low-grade waste heat into acoustic power. Many existing studies have pointed out the acoustic-to-electric potential of thermo-acoustic systems. Hence in this work, a thermo-acoustic system has been developed. The traveling-wave system has a total length of 3 560 mm. The distance between each thermo-acoustic engine is 640 mm. Each engine stage had four cartridge heaters used to generate the heat required. A commercial loudspeaker was used to convert sound into electricity. The minimum temperature difference necessary to induce a voltage at the terminals of the loudspeaker was approximately 200oC. The four-stage traveling-wave system generated the highest output voltage of 4.218 V.