In this study, the hot-wire anemometry is used to investigate the high-amplitude velocity oscillations inside a parallel-plate stack of a standing-wave thermoacoustic resonator. The ratio of the peak acoustic pressure amplitude to the ambient pressure, defined as the drive ratio (Dr), ranges from 0.3 to 6.0%. The applicability of hot-wire anemometry technique for a time-resolved velocity measurement is studied, typically at a low Dr of 0.5%, in which the condition the flow is very likely to remain laminar. At higher drive ratios, turbulent bursts start to be generated and the velocity waveform becomes strongly fluctuating. By comparing the velocity fluctuations measured in different regions of the viscous boundary layer, the transition behaviour is analyzed. The importance of this study lies in developing reliable measurement techniques for use in thermoacoustic systems and a critical analysis of the capabilities of the hot-wire anemometry in particular.
|Title of host publication
|Proceedings of the 22nd IIR International Congress of Refrigeration (ICR 2007)
|Number of pages
|Published - 21 Aug 2007