Title :
Laser Doppler Velocimeter Development
Author :
Seegmiller, H. Lee ; Bader, Jan B. ; Cooney, John P. ; DeYoung, Anemarie ; Donaldson, Ralph W., Jr. ; Gunter, William D., Jr. ; Harrison, Dean R.
Author_Institution :
NASA Ames Research Center, Moffett Field, California 94035, U.S.A.
fDate :
5/1/1986 12:00:00 AM
Abstract :
A new two-channel laser Doppler velocimeter developed for the Ames High Reynolds Channel No. II is described. Design features required for the satisfactory operation of the optical system in the channel environment are discussed. Fiber optics are used to transmit the megahertz Doppler signal to the photodetectors located outside the channel pressure vessel, and provision is made to isolate the optical system from pressure and thermal strain effects. Computer-controlled scanning mirrors are used to psoition the laser beams in the channel flow. Techniques used to seed the flow with 0.5-¿-diam polystyrene spheres avoiding deposition on the test-section windows and porous boundary-layer removal panels are described. Preliminary results are presented with a discussion of several of the factors affecting accuracy.
Keywords :
Automotive components; Image motion analysis; Light scattering; Optical filters; Optical noise; Optical scattering; Optical sensors; Particle measurements; Testing; Velocity measurement;
Journal_Title :
Aerospace and Electronic Systems Magazine, IEEE
DOI :
10.1109/MAES.1986.5005112