Fishbone-like instability in a looped-tube thermoacoustic engine

• Published in: The Journal of the Acoustical Society of America Vol. 128; no. 4; pp. EL188 - EL194
• Main Authors: Yu, Zhibin, Jaworski, Artur J., Abduljalil, Abdulrahman S.
• Format: Journal Article
• Language: English
• Published: Melville, NY Acoustical Society of America 01-10-2010; American Institute of Physics
• Subjects: Acoustics; Amplitudes; Applied sciences; Bursts; Energy; Energy. Thermal use of fuels; Engineering - instrumentation; Engines; Engines and turbines; Equipment Design; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Instability; Models, Theoretical; Oscillations; Oscillometry; Pressure; Sound; Sound Spectrography; Stability; Temperature; Thermoacoustics; Time Factors; Instability; Thermoacoustic effect; Engine
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.3486198

Quasi-periodic bursts of acoustic oscillations were observed during the start-up process in a looped-tube thermoacoustic engine. The acoustic oscillations have a constant frequency of 111 Hz, while the bursts have "quasi-periods" in the order of 14-25 s. The quasi-periodic bursts show a new mode of amplitude growth in this thermoacoustic engine. The envelope of the acoustic oscillations has a fishbone-like shape. The nature of the observed fishbone-like instabilities suggests a strong interaction between the acoustic and temperature field.