Journal of Flow Visualization and Image Processing

ISSN for PRINT: 1065-3090

For Online Access

Best Paper Award Selection - Editorial Board Site

2005, Volume12

Issue 3

138 pages

DOI: 10.1615/JFlowVisImageProc.v12.i3

Issue price - $154.00

Nengli Zhang
Ohio Aerospace Institute at NASA Glenn Research Center, Cleveland, OH 44135, USA

David F. Chao
Fluid Physics and Transport Branch, NASA Glenn Research Center, Cleveland, OH 44135, USA

Wen-Jei Yang
Department of Mechanical Engineering and Applied Mechanics, University of Michigan, Ann Arbor, Michigan 48109, U.S.A.

Optical catastrophe occurring in a far field of waves of a drop-refracted laser beam implies a wealth of information about drop spreading. The present paper reveals, based on catastrophe optics, that the far-field caustic images can successfully detect the interface instability of sessile drops, measure the contact angles of the drops, estimate the drop-foot height, visualize capillary flows in the drops, and investigate the spreading characteristics of evaporating liquid drops, such as the drop profile at the three-phase line, the effects of evaporation and capillary flows on the spreading, etc. All of these obviously are very important for the study of spreading of evaporating liquid drops. As an example of the applications, three typical volatile liquid drops were tested using the far-field caustic images of the drop-refracted laser beam. The effects of evaporation and thermocapillary convection on the spreading are revealed and discussed.

DOI: 10.1615/JFlowVisImageProc.v12.i3.50 Download article, 285-300 pages

Article price - $35.00

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