Principles of Laser Doppler anemometry

• Concisely explained principles and main aspects of the LDA technique
• Shown in animated form in three minutes; no complicated math formulas and no difficult theory.
• It is just good to view it with stopping the video and repeating due to the concentrated amount of information wich could be difficult to catch on the first sight.
Laser Doppler anemometry (LDA) greatly advanced experiments in multiphase flows, providing accurate non-intrusive flow measurements with directional sensitivity, high spatial and temporal resolution. It suits for complex flows with separation regions and flow reversals. Before its introduction hot-wire anemometry was the only means to directly measure single-point turbulence quantities.
Laser Doppler anemometry, also known as laser Doppler velocimetry (LDV) came into widespread use in the 1970s. The instruments became standard and commercially available.
LDA technique is a point-wise optical measuring method to provide Eulerian description of the flow field with embedded fluid markers. It gives statistical moments of the flow velocity.
The LDA was first presented by Yeh and Cummins in 1964, and with its widespread use in fluid mechanics, we refer to reviews and monographs (Durst et al. (1981), Zhang (2010), Albrecht (2003)) for details.
Albrecht, H.-E., 2003, Laser Doppler and phase Doppler measurement techniques, Springer, Berlin ; New York.
Durst, F., A. Melling, and J. Whitelaw. 1981. Principles and Practices of LaserDoppler Anemometry. Academic Press.
Zhang, Z., 2010. LDA Application Methods Laser Doppler Anemometry for Fluid Dynamics, Experimental Fluid Mechanics. Springer, Berlin; London.