Abstract

A new method is reported for measuring the velocity gradient using a transmission grating. The velocity gradient is determined from the difference of velocities at two probed regions of the moving object. The principle of the method is theoretically described on the basis of transmission grating velocimetry. The experiments were performed using both the tip face of a 6-mm diam rotating axis of a dc motor and the water flowing in a small (700-μm diam) cylindrical glass tube. Theoretical and experimental results show the usefulness of this method for measuring the velocity gradient in a microscopic region.

© 1985 Optical Society of America

Measurements of flow velocity in a microscopic region using a transmission grating: a differential type

Yoshihisa Aizu, Tsuyoshi Ushizaka, and Toshimitsu Asakura
Appl. Opt. 24(5) 627-635 (1985)

Measurements of flow velocity in a microscopic region using a transmission grating: elimination of directional ambiguity

Yoshihisa Aizu, Tsuyoshi Ushizaka, and Toshimitsu Asakura
Appl. Opt. 24(5) 636-640 (1985)

Measurements of flow velocity in a microscopic region using a transmission grating

Tsuyoshi Ushizaka and Toshimitsu Asakura
Appl. Opt. 22(12) 1870-1874 (1983)

Measurements of flow velocity in a microscopic region using a transmission grating: a practical velocimeter

Yoshihisa Aizu, Tsuyoshi Ushizaka, Toshimitsu Asakura, and Tomiyasu Koyama
Appl. Opt. 25(1) 31-38 (1986)

Gas velocity measurements using photothermal deflection spectroscopy

Jeffrey A. Sell
Appl. Opt. 24(22) 3725-3735 (1985)