TY - JOUR
T1 - Sphere motion in ordered three-dimensional foams
AU - Davies, I. T.
AU - Cox, Simon
N1 - I.T. Davies and S.J. Cox (2012) Sphere motion in ordered three-dimensional foams. J. Rheol. 56:473-483.
PY - 2012/4/4
Y1 - 2012/4/4
N2 - The effect of the interplay between surface tension and gravity on the sedimentation of objects in
structured fluids is investigated by simulating the quasi-static motion of a spherical particle through
an ordered foam. We describe the path which a sphere takes as it descends through bamboo (1,1,0),
staircase (2,1,1), chiral (3,2,1), and double staircase (4,2,2) foams, and measure the degree of control of the sphere’s motion that each foam offers. For an ordered foam contained within a vertical
cylinder, the resulting sphere motion depends strongly on the structure itself, on how the films are
deformed near the sphere, and on how the motion of the sphere deforms them further. For staircase
and chiral foams, the distance that a sphere is pulled away from the center-line of the cylinder by
the foam is found to depend on the Bond number with a power-law relation. By tilting the cylinder
at an angle to the vertical, we show that there exists a critical tilt angle above which the sphere falls
out of the foam. This angle is dependent on the choice of foam structure and the Bond number. For
a sphere of given size and given Bond number in the ordered foams studied here, the greatest tilt
can be imposed on the double staircase foam
AB - The effect of the interplay between surface tension and gravity on the sedimentation of objects in
structured fluids is investigated by simulating the quasi-static motion of a spherical particle through
an ordered foam. We describe the path which a sphere takes as it descends through bamboo (1,1,0),
staircase (2,1,1), chiral (3,2,1), and double staircase (4,2,2) foams, and measure the degree of control of the sphere’s motion that each foam offers. For an ordered foam contained within a vertical
cylinder, the resulting sphere motion depends strongly on the structure itself, on how the films are
deformed near the sphere, and on how the motion of the sphere deforms them further. For staircase
and chiral foams, the distance that a sphere is pulled away from the center-line of the cylinder by
the foam is found to depend on the Bond number with a power-law relation. By tilting the cylinder
at an angle to the vertical, we show that there exists a critical tilt angle above which the sphere falls
out of the foam. This angle is dependent on the choice of foam structure and the Bond number. For
a sphere of given size and given Bond number in the ordered foams studied here, the greatest tilt
can be imposed on the double staircase foam
U2 - 10.1122/1.3687415
DO - 10.1122/1.3687415
M3 - Article
SN - 0148-6055
VL - 56
SP - 473
EP - 483
JO - Journal of Rheology
JF - Journal of Rheology
IS - 3
ER -