caa a22 4500 477093817 CHVBK 20180405111521.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00189056 doi (NATIONALLICENCE)springer-10.1007/BF00189056 Optical measurement of liquid film thickness and wave velocity in liquid film flows [Elektronische Daten] [E. Hurlburt, T. Newell] Two optical techniques are described for measurement of a liquid film's surface. Both techniques make use of the total internal reflection which occurs at a liquid-vapor interface due to the refractive index difference between a liquid and a vapor. The first technique is used for film thickness determination. A video camera records the distance between a light source and the rays which are reflected back from the liquid-vapor interface. This distance can be shown to be linearly proportional to film thickness. The second technique measures surface wave velocities. Two photo sensors, spaced a fixed distance apart, are used to record the time varying intensity of light reflected from the liquid-vapor interface. The velocity is then deduced from the time lag between the two signals. Springer-Verlag, 1996 Hurlburt E. Dept. of Mechanical and Industrial Engineering, University of Illinois at Urbana-Champaign, 1206 W. Green St, 61801, Urbana, IL, USA aut Newell T. Dept. of Mechanical and Industrial Engineering, University of Illinois at Urbana-Champaign, 1206 W. Green St, 61801, Urbana, IL, USA aut Experiments in Fluids Springer-Verlag 21/5(1996-09-01), 357-362 0723-4864 21:5<357 1996 21 348 https://doi.org/10.1007/BF00189056 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00189056 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hurlburt E. Dept. of Mechanical and Industrial Engineering, University of Illinois at Urbana-Champaign, 1206 W. Green St, 61801, Urbana, IL, USA aut NATIONALLICENCE 700 1- Newell T. Dept. of Mechanical and Industrial Engineering, University of Illinois at Urbana-Champaign, 1206 W. Green St, 61801, Urbana, IL, USA aut NATIONALLICENCE 773 0- Experiments in Fluids Springer-Verlag 21/5(1996-09-01), 357-362 0723-4864 21:5<357 1996 21 348 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer