Skip to Main content Skip to Navigation
Theses

Contributions expérimentales sur la dynamique instationnaire de bulles de Taylor

Abstract : The present work deals with the motion of a Taylor bubble rising through vertical oscillating pipes. The aim is to perform a more detailed and experimental quantitative study of this unsteady flow, still seldom addressed in the literature. The investigation is restricted to high Reynolds numbers to understand inertia effects. Experimental results are provided for two different configurations : 1) pipes with two different inner diameters (9.8 mm and 20 mm) filled with water, 2) the thinner pipe (D=9.8 mm) filled with four low viscous fluids. So the Bond number Bo, based on the steady rise velocity varies from 13 to 57, where the effects of surface tension can be considered. The bubble trajectory is tracked by using a high-speed video camera. The average terminal and fluctuating velocity, as well as the phase shift with the oscillating plate are obtained by using image processing. The main results show that for weak acceleration, the mean velocity decreases with the relative acceleration as the fluctuating velocity increases in proportion to this acceleration. Beyond a critical relative acceleration, the average velocity increases and the fluctuating velocity increase seems to slow down. This behavior change seems to be related to the interface deformation (modified curvature, surface waves) which becomes significant in high accelerations. Additionally, comparisons are made with the numerical results obtained by neglecting the capillary effects. Correlations allowing the prediction of mean and fluctuating velocities depending on the Bond number and relative acceleration are proposed and compared with our experimental results. The time evolution of the radii of curvature in the vicinity of the bubble nose is also studied for different relative accelerations and the results are compared with the stagnant case. In high accelerations, the formation and propagation of surface waves which may influence the bubble dynamics are quantified
Complete list of metadata

Cited literature [71 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01748821
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 11:50:13 AM
Last modification on : Monday, March 29, 2021 - 4:03:09 PM
Long-term archiving on: : Friday, September 14, 2018 - 4:34:17 AM

File

2010_MADANI_S_S.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01748821, version 1

Collections

Citation

Seyedeh Sara Madani. Contributions expérimentales sur la dynamique instationnaire de bulles de Taylor. Autre. Institut National Polytechnique de Lorraine, 2010. Français. ⟨NNT : 2010INPL009N⟩. ⟨tel-01748821⟩

Share

Metrics

Record views

60

Files downloads

60