Hot-film anemometry in bubbly flow: Bubble-probe interaction

Rensen, Judith and Luther, Stefan and Vries de, Joris and Lohse, Detlef (2005) Hot-film anemometry in bubbly flow: Bubble-probe interaction. International Journal of Multiphase Flow, 31 (3). pp. 285-301. ISSN 0301-9322

PDF
Restricted to UT campus only: Request a copy
609Kb

Abstract:	The interaction between a bubble, which is rising in a descending water flow, and a hot-film anemometer was experimentally investigated using stereoscopic high-speed imaging. The mean downward water velocity varied from 0 up to 0.15 m/s, i.e., relatively low, allowing for an extended bubble¿probe interaction. Moreover, the direction of the water causes the wake of the probe to play a role before the bubble touches the probe. The equivalent bubble radii were 0.4¿2.8 mm and the bubble velocities relative to the probe ranged from 0.04 to 0.38 m/s. Image processing techniques were applied to reconstruct the bubbles path, shape, and orientation during the interaction process. As a result, three types of interactions were found, namely penetrating, bouncing, and splitting interactions. The image sequences were compared with the corresponding time series of the hot-film anemometer. From the time series the type of interaction cannot be deduced, at least not for the analyzed flow situation. Furthermore, we demonstrated that the residence time estimate from the hot-film data is systematically biased in our type of experiments. Finally, it was found that the velocity of a bubble may be altered considerably due to the interaction.
Item Type:	Article
Copyright:	© 2004 Elsevier
Faculty:	Science and Technology (TNW)
Research Group:	Physics of Fluids (POF)
Link to this item:	http://purl.utwente.nl/publications/54111
Official URL:	http://dx.doi.org/10.1016/j.ijmultiphaseflow.2004.11.005
Export this item as:	BibTeX EndNote HTML Citation Reference Manager

Show download statistics for this publication

Repository Staff Only: item control page

Metis ID: 227784