Local Flow Speed Measurement Using Tunable AC Thermal Anemometry

  • Chung Won Seok (Micro Thermal System Research Center, Seoul National University) ;
  • Kwon Ohmyoung (Department of Mechanical Engineering, Korea University) ;
  • Lee Joon Sik (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Choi Young Ki (School of Mechanical Engineering, Chung-Ang University) ;
  • Park Seungho (Department of Mechanical and System Design Engineering, Hongik University)
  • 발행 : 2005.07.01

초록

This paper shows the results of local flow speed measurement using tunable AC thermal anemometry, which is suitable for the accurate measurement of wide range flow speed. The measurement accuracy is verified through the comparison between the measurement data and the analytic solution of the sensor temperature oscillation in stationary fluid. The relation between the phase lag and the flow speed is experimentally investigated at various conditions. The measurement sensitivity for low flow speed improves in a low frequency region and that for high flow speed improves in a high frequency region. Also, the sensitivity increases with decreasing thermal conductivity of the surrounding fluid. The local flow speed could be measured as low as 1.5 mm/s and the highest measurement resolution was 0.05 mm/s in the range of 4.5 $\~$5.0 mm/s at 1 Hz in this experiment.

키워드

참고문헌

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