Basic study for practical use of thermoacoustic electric generation system

An electrical generation system using thermoacoustic phenomena is proposed, as a technology to improve global warming and energy resource depletion. A loudspeaker is used as, an electroacoustic converter of the magnetic induction method in this study. A loop-tube-type thermoacoustic system(loop tube) is used as the prototype system. The open-end-type resonance tube, with the length adjusted to 1/4 length of the loop tube, is added on the loop tube system to realize stable sound generation. The possibility of electrical generation was investigated using the presented prototype system. Stable sound generation is observed even if a part of the loop tube is opened. The prototype system consists of the 3300 mm length of the loop tube, and 825 mm length of resonance tube. The inner diameter of each tube is 42 mm. The full-range loudspeaker is located at the end of resonance tube and the energy conversion from heat to electricity is observed in various conditions. The sound pressure level of more than 160 dB is realized using the presented system. Results demonstrate electrical generation capability of 1.1 W active power using the proposed thermoacoustic system.