LDA Worked Example

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To measure the velocity at a point in the fluid, flowing in a transparent walled channel, a laser light beam of wavelength 680nm is used to illuminate the small particles in the flow at 90, as shown in the figure. The light scattered by particles is detected by a photodetector that is inclined to the channel with = 30. If u = 25m/s, calculate the Doppler shift, fD. u 680nm laser light beam photodetector

description

Laser Doppler Anemometry

Transcript of LDA Worked Example

Page 1: LDA Worked Example

To measure the velocity at a point in the fluid, flowing in a transparent walled channel, a laser light

beam of wavelength 680nm is used to illuminate the small particles in the flow at 90, as shown

in the figure. The light scattered by particles is detected by a photodetector that is inclined to the

channel with = 30. If u = 25m/s, calculate the Doppler shift, fD.

u

680nm laser light beam

photodetector