Journal
MEASUREMENT
Volume 44, Issue 7, Pages 1300-1311Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.measurement.2011.03.020
Keywords
Free surface dynamics; Liquid film; Microfluidics; Optical imaging; Image analysis
Funding
- Ministerio de Educacion y Ciencia(Spain) [DPI2010-21103]
- Junta de Extremadura [GRU07003]
Ask authors/readers for more resources
We evaluate the precision of backlight optical imaging to locate the position of a free surface close to the diffraction limit. For this purpose, we acquired and processed images of liquid films at equilibrium deposited on a capillary 10 mu m in diameter. The detected contours were compared with the solution of the exact Young-Laplace equation. Deviations of about 10 nm were obtained, which constitutes the first quantitative validation of backlight optical imaging for fluid shapes a few microns in size. The local mean curvature measured in the experiments agreed remarkably with the theoretical values. We illustrate the applicability of this technique by analysing five interfacial phenomena: (i) the flow in the tip of a capillary tapering meniscus formed by flow focusing, (ii) the extensional deformation of viscous micro-jets by the action of a co-flowing gas stream, (iii) the growth of small-amplitude capillary waves on a micro-jet free surface, (iv) the flow in the tip of a capillary tapering meniscus produced by electrospray, and (v) the characterization of glass micro-nozzles. (C) 2011 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available