Abstract

A technique is presented for measurements of two-dimensional velocity fields in gas flows. The single-mode frequency of an argon-ion laser is fixed in the wing of an absorption line of iodine molecules that are seeded at low level in the flow of interest. The emitted fluorescence is detected with an image-intensified 100 × 100 photodiode-array camera. Two pairs of counterpropagating laser sheets sequentially probe the flow to determine two velocity components. The frequency in one pair is shifted with respect to the other by an acousto-optic modulator. This two-frequency scheme eliminates the need to determine the slope of the line externally and offers the potential for combined pressure and velocity-field measurements.

© 1985 Optical Society of America

Laser-induced fluorescence technique for velocity field measurements in subsonic gas flows

B. Hiller, J. C. McDaniel, E. C. Rea, and R. K. Hanson
Opt. Lett. 8(9) 474-476 (1983)

Planar velocity measurement in symmetric flow fields with laser-induced iodine fluorescence

Steven D. Hollo, Roy J. Hartfield, and James C. McDaniel
Opt. Lett. 19(3) 216-218 (1994)

Simultaneous planar measurements of velocity and pressure fields in gas flows using laser-induced fluorescence

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Appl. Opt. 27(1) 33-48 (1988)

Simultaneous multiple-point velocity measurements using laser-induced iodine fluorescence

J. C. McDaniel, B. Hiller, and R. K. Hanson
Opt. Lett. 8(1) 51-53 (1983)

Instantaneous temperature field measurements using planar laser-induced fluorescence

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