Velocity Bias Associated With Laser Doppler Anemometer Controlled Processors

[+] Author and Article Information
A. R. Winter, L. J. W. Graham, K. Bremhorst

Department of Mechanical Engineering, The University of Queensland, Queensland 4072, Australia

J. Fluids Eng 113(2), 250-255 (Jun 01, 1991) (6 pages) doi:10.1115/1.2909488 History: Received April 04, 1990; Online May 23, 2008


The controlled processor has been proposed as a means of avoiding velocity bias in laser Doppler anemometry. A theoretical model is presented to show that results free of bias can be obtained if both the ratio of integral time scale to measurement time scale (integral scale data density) and the ratio of sampling time to the measurement time scale (normalized sample interval) are greater than five. Further, by separation of the integral scale data density and normalized sample interval parameters, it is shown that at any integral scale data density the controlled processor will not produce any less bias than a sample and hold processor and no more bias than the free running (unweighted) processor. In some situations it may be considered superior to the sample and hold processor as the data processing and hardware requirements are reduced without any loss of measurement accuracy. Experimental data confirming the theoretical results are also shown. Some of these data are contrary to at least one model available in the literature.

Copyright © 1991 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.





Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In