A laser-induced fluorescence (LIF) technique is employed for visualizing a thin two-dimensional (2D) dissolved oxygen concentration field and measuring local oxygen concentration gradients near the surface of an oxygen bubble in water containing surfactant (Triton X-100, SigmaAldrich, St Louis, MO, USA)). The fluorescence of pyrene butyric acid (PBA) is induced by a planar pulse of nitrogen laser light. Oxygen transferring from the bubble to the deoxygenated water quenches the fluorescence of the PBA. Images of the fluorescence fields are captured by a UV-intensified CCD camera. The intensity of fluorescence quenching at each image pixel is used to measure dissolved oxygen concentration in a 2D field. Images of bubbles are obtained at 200 ppm, 100 ppm, and 50 ppm Triton X-100-containing water and in ultra clean deionized water. Higher surfactant concentrations decrease local and average concentration gradients of oxygen at the bubble surface. The ensemble means of dissolved oxygen concentration boundary layer thicknesses of 0.160 mm, 0.130 mm, and 0.072 mm, for the images of bubbles obtained at 200 ppm, 100 ppm, and 50 ppm Triton X-100-containing water, respectively. Local concentration boundary layer thickness increases from the top to the bottom along the bubble surface. A series of images of the bubble flow fields are analyzed to measure the oxygen concentration gradients in water in the presence of surfactant. The images captured in clean water are not fully resolvable because of their poor resolution. The formation of the attached wake in the fluorescence field images at the bottom of the bubbles in clean water tends to be promoted by increasing oblateness owing to the presence of surfactant at the surface.
Experiments in Fluids – Springer Journals
Published: Feb 21, 2004
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera