DOI QR코드

DOI QR Code

The Analysis of Acoustic Waves generated by a TA(ThermoAcoustic) Laser Pair

열음향(Thermoacoustic) 레이저의 음향파 특성 분석

  • Oh, Seung-Jin (Dept. of Nuclear and Energy Engineering, Jeju National University) ;
  • Chen, Kuan (Dept.of Mechanical Engineering, University of Utah) ;
  • Lee, Yoon-Joon (Dept. of Nuclear and Energy Engineering, Jeju National University) ;
  • Shin, Sang-Woong (Dept. of Nuclear and Energy Engineering, Jeju National University) ;
  • Lim, Sang-Hoon (Korea Institute of Energy Research) ;
  • Chun, Won-Gee (Dept. of Nuclear and Energy Engineering, Jeju National University)
  • Received : 2011.07.26
  • Accepted : 2011.12.05
  • Published : 2011.12.30

Abstract

Sound waves and acoustic energy generated by two identical TA (ThermoAcoustic) lasers were analyzed and studied. One end of the ceramic stack was heated by a thin NiCr wire wound around that end. The other end of the stack was cooled by natural convection of atmospheric air. The wavelength of the sound waves generated by a single TA laser was four times the tube length and the amplitude of the waves increased with the heating rate. SPL (SoundPressure Level) meters and microphones were employed to measure and study the sound waves at different distances from the glass tube opening and at the focusing point of the TA laser pair for different laser position arrangements. The sound waves of the two TA lasers at the focusing point were found to be almost 180 degrees out of phase when the openings of the two lasers were very close to each other and the angle between the laser axes was small. When the two TA lasers were placed far apart, the sound wave amplitudes and the phase difference between the two laser outputs varied periodically with time. The frequencies of the sound waves changed when the openings of the two TA lasers were in close vicinity and the angle between the laser axes exceeded a certain value. In this case, the glass tube opening was no longer a pressure anti-node and the wavelength of the fundamental mode was not equal to four times the tube length.

Keywords

References

  1. Arnott WP, Raspet P, Bass HE. 1991. Thermoacoustic engines. Proceedings of IEEE Ultrasonics Society. Editor : McAvory BR. : 995-1003.
  2. Bass HE, Raspet R, Belcher JR, Brewster J. 1995. A study of element interaction in thermoacoustic engines. Annual Report of ONR Grant # N00014-93-1-0077.
  3. Chen G, Ke T, Tao J. 2004. Advances in thermoacoustic engine and it application to pulse tube refrigeration. Chinese Science Bulletin 49(13) : 1319-1328 https://doi.org/10.1360/03te0190
  4. Chen RL,Garrett SL.1998. The solar/heat driven thermoacoustic engine. J. Acoust. Soc .Am. 103(5) : 2841-2842.
  5. Donald F, Thermoacoustic Oscillations, Wave Motion & Optics Spring 2006.
  6. Gardner DL, Swift GW. 2003. A cascade thermoacoustic engine. J. Acoust. Soc. Am. 114 (4): 1905-1919. https://doi.org/10.1121/1.1612483
  7. Nguyen AT. 2004. Creating sound with heat. California State Science Fair 2004 (http://www.usc.edu/CSSF/History/2004). Project number S1516
  8. Rodriguez IA, Symko OG. 2010. Heat to electricity using thermoacoustics. Abstract # Y29.012. American Physical Society. APS March Meeting 2010.
  9. Shen C, He Y, Li Y, Ke H, Zhang D, Liu Y. 2009. Performance of solar powered thermoacoustic engine at different tilted angles. Applied Thermal Engineering 29(13): 2745-2756. https://doi.org/10.1016/j.applthermaleng.2009.01.008
  10. Symko OG, Abdel-Rahman E, Kwon YS, Emmi M, Behunin R. 2004, Design and development of high-frequency thermoacoustic engines for thermal management in microelectronics. Microelectronics J. 35: 185-191. https://doi.org/10.1016/j.mejo.2003.09.017
  11. Swift GW. 2002. Thermoacoustics - A Unifying Perspective for Some Engines and Refrigerators. Publisher : Acoustical Society of America, Melville, NY.
  12. Tontechnik-Rechner-sengpielaudio. 2010. Sound pressure p and the inverse distance law 1/r.Retrieved fromhttp://www.sengpielaudio.com/calculator-distancelaw.htm.July2010.