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Production of Gas Bubbles in Reduced Gravity EnvironmentsIn a wide variety of applications such as waste water treatment, biological reactors, gas-liquid reactors, blood oxygenation, purification of liquids, etc., it is necessary to produce small bubbles in liquids. Since gravity plays an essential role in currently available techniques, the adaptation of these applications to space requires the development of new tools. Under normal gravity, bubbles are typically generated by forcing gas through an orifice in a liquid. When a growing bubble becomes large enough, the buoyancy dominates the surface tension force causing it to detach from the orifice. In space, the process is quite different and the bubble may remain attached to the orifice indefinitely. The most practical approach to simulating gravity seems to be imposing an ambient flow to force bubbles out of the orifice. In this paper, we are interested in the effect of an imposed flow in 0 and 1 g. Specifically, we investigate the process of bubble formation subject to a parallel and a cross flow. In the case of parallel flow, we have a hypodermic needle in a tube from which bubbles can be produced. On the other hand, the cross flow condition is established by forcing bubbles through an orifice on a wall in a shear flow. The first series of experiments have been performed under normal gravity conditions and the working fluid was water. A high quality microgravity facility has been used for the second type and silicone oil is used as the host liquid.
Document ID
19970000379
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Oguz, Hasan N.
(Johns Hopkins Univ. Baltimore, MD United States)
Takagi, Shu
(Tokyo Univ. Japan)
Misawa, Masaki
(Mechanical Engineering Lab. Tsukuba, Japan)
Date Acquired
August 17, 2013
Publication Date
September 1, 1996
Publication Information
Publication: Third Microgravity Fluid Physics Conference
Subject Category
Materials Processing
Accession Number
97N10346
Funding Number(s)
CONTRACT_GRANT: NSF CTS-93-18724
CONTRACT_GRANT: NSF CTS-95-06077
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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