| Issue |
EPL
Volume 78, Number 6, June 2007
|
|
|---|---|---|
| Article Number | 68007 | |
| Number of page(s) | 5 | |
| Section | Interdisciplinary Physics and Related Areas of Science and Technology | |
| DOI | https://doi.org/10.1209/0295-5075/78/68007 | |
| Published online | 04 June 2007 | |
Drag on a sphere moving through an aging system
1
Department of Physics and Astronomy, University of Western Ontario - London, ON N6A 3K7, Canada
2
Institut Navier - Paris, France
Received:
4
January
2007
Accepted:
7
May
2007
We have investigated the drag on a sphere falling through a clay suspension that has a yield stress and exhibits rheological aging. The drag force increases with both speed and the rest time between the preparation of the system and the start of the experiment, but there exists a non-zero minimum speed below which steady motion is not possible. We find that only a very thin layer of material around the sphere is fluidized when it moves, while the rest of the suspension is deformed elastically. This is in marked contrast to what is found for yield-stress fluids that do not age.
PACS: 82.70.-y – Disperse systems; complex fluids / 83.60.La – Viscoplasticity; yield stress / 64.70.Pf – Glass transitions
© Europhysics Letters Association, 2007
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.