Acoustic Doppler Velocimeter in Measurements of Turbulent Boundary Layer Flows

Abstract:

Acoustic Doppler Velocimeter (ADV)’s applications in measuring velocity profiles of turbulent boundary layers (TBLs) are investigated at a flow Reynolds number of 36000 in a lab-made open channel. The 3D instantaneous velocity signals at different heights of TBLs are obtained, which present very strong abnormal noises in the near wall regions because of the aliasing of Doppler signal spectra. The minimum/maximum threshold filter is adopted for the signal to remove the noises reflected by walls. The mean streamwise velocities and turbulence intensities profiles are then calculated correctly. The measuring results consist with the law of turbulent boundary layer flow. The ADV has a good performance in measurements of TBLs with a simple implementation of filter to the sampled velocity signals. The present research is guidable for applications of ADV in practice.

• Periodical: Applied Mechanics and Materials (Volumes 239-240)
• Pages: 100-103
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.239-240.100
• Online since: December 2012
• Authors: Hao Lu, Bing Wang, Hui Qiang Zhang, Xi Lin Wang
• Keywords: Acoustic Doppler Velocimeter, Threshold Filter Method, Turbulent Boundary Layer, Turbulent Intensity

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