Results 251 to 260 of about 402,207 (298)

Bubble sizing with a high spatial resolution

IEEE 1988 Ultrasonics Symposium Proceedings., 1990
The authors propose a technique that allows them to size bubbles with the same accuracy as with the double-frequency method and to locate them with the same range resolution as with the pulsed Doppler velocimeter. They demonstrate that the signal scattered by the bubble insonified by a high-frequency pulsed ultrasonic field and a low-frequency pumping ...
D, Cathignol, J Y, Chapelon, V L, Newhouse, P M, Shankar   +3 more
openaire   +2 more sources

Bubble Size Distribution in Oil‐Based Bubble Columns

Chemical Engineering & Technology, 2008
AbstractA practical population balance model was used to evaluate the bubble size distribution in a bubble column. In addition, the bubble size distribution in the bubble column was measured at different gas velocities by photography and analysis of the pictures.
S.‐S. Homayouni, M.‐R. Mehrnia, N. Mostoufi, M. Rajabi, A. Yazdani   +4 more
openaire   +1 more source

Bubble size and bubble velocity distribution in bubble columns under industrial conditions

The Canadian Journal of Chemical Engineering, 2017
Bubble column reactors are widely used in many industrial applications due to their simplicity and safety of operation. Despite these advantages, the design and scale‐up of bubble column reactors is still challenging especially for industrial conditions at elevated pressure and temperature.
Bothe, Melanie, Christlieb, Marc-Andreas, Hoffmann, Marko, Tedjasukmana, Osmond, Michaux, Frank, Rollbusch, Philipp, Becker, Marc, Schlüter, Michael   +7 more
openaire   +1 more source

Bubble‐Size distributions and flow fields in bubble columns

AIChE Journal, 2002
AbstractBubble‐size distributions and flow fields in bubble columns are calculated numerically. The population balance is simplified and reduced to a balance equation for the average bubble volume. Models developed predict the rate of bubble breakup and coalescence based on physical principles.
F. Lehr, M. Millies, D. Mewes
openaire   +1 more source

Developed ‘laminar’ bubbly flow with non-uniform bubble sizes

Science in China Series E: Technological Sciences, 2001
Bubbles with different sizes have different dynamic and kinetic behavior in a two-phase bubbly flow. A common two-fluid model based on the uniform bubble size assumption is not suitable for a bubbly flow with non-uniform bubble sizes. To deal with non-uniform bubbly flows, a multi-fluid model is established, with which bubbles are divided into several ...
Rui Luo, Qiang Song, Xianyong Yang, Zhou Wang   +3 more
openaire   +1 more source

Lognormal bubble size distributions

The Journal of the Acoustical Society of America, 2017
In the study of oceanic bubbles based on empirical acoustics, the distributions among the sizes are typically represented by power laws with negative slopes as convenient descriptors of data in log/log format. However, power laws do not address the fact that as bubble sizes approach zero their numbers must approach zero.
openaire   +1 more source

Influence of bubble size on micro-bubble drag reduction

Experiments in Fluids, 2006
Micro-bubble drag reduction experiments were conducted in a turbulent water channel flow. Compressed nitrogen was used to force flow through a slot injector located in the plate beneath the boundary layer of the tunnel test section. Gas and bubbly mixtures were injected into a turbulent boundary layer (TBL), and the resulting friction drag was measured
Xiaochun Shen, Steven L. Ceccio, Marc Perlin   +2 more
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Fast bubble dynamics and sizing

Journal of Sound and Vibration, 2015
Abstract Single bubble sizing is usually performed by measuring the resonant bubble response using the Dual Frequency Ultrasound Method. However, in practice, the use of millisecond-duration chirp-like waves yields nonlinear distortions of the bubble oscillations.
Czarnecki, K., Fouan, D., Achaoui, Y., Mensah, S   +3 more
openaire   +2 more sources

Bubble size effects in foams

International Journal of Heat and Fluid Flow, 1987
Abstract The problem of measuring bubble size distribution in liquid-gas foams is discussed. Results of some bubble size measurements are presented, and an attempt is made to relate the bubble size information to the rheological properties of the foam.
J.R. Calvert, K. Nezhati
openaire   +1 more source

Bubble size in horizontal pipelines

AIChE Journal, 1987
Bubble sizes for dilute dispersion in horizontal pipelines under turbulent liquid flow conditions are shown to be predicted by a theory. This theory contains the dependence of dispersed-phase density on the bubble size, which is not included in theories presented by others.
R. P. Hesketh, T. W. Fraser Russell, A. W. Etchells   +2 more
openaire   +1 more source