Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2009-07-06
Physics
Condensed Matter
Soft Condensed Matter
submitted to J. Rheol; frst resubmission
Scientific paper
The 2D flow of a foam confined in a Hele-Shaw cell through a contraction is investigated. Its rheological features are quantified using image analysis, with measurements of the elastic stress, rate of plasticity, and velocity. The behavior of the velocity strongly differs at the contraction entrance, where the flow is purely convergent, and at the contraction exit, where a velocity undershoot and a re-focussing of the streamlines are unraveled. The yielded region, characterized by a significant rate of plasticity and a maximal stress amplitude, is concentrated close to the contraction. These qualitative generic trends do not vary significantly with the flow rate, bubble area and contraction geometry, which is characteristic of a robust quasistatic regime. Using surfactants with a high surface viscoelasticity, a marked dependence of the elastic stress on the velocity is exhibited. The results show that the rate of plasticity does not only depend on the local magnitude of the deformation rate, but also crucially on the orientation of both elastic stresses and deformation rate. It is also discussed how the viscous friction controls the departure from the quasistatic regime.
No associations
LandOfFree
Local description of the two-dimensional flow of foam through a contraction does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Local description of the two-dimensional flow of foam through a contraction, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local description of the two-dimensional flow of foam through a contraction will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-27433