TY - JOUR

T1 - Yield drag in a two-dimensional foam flow around a circular obstacle

T2 - Effect of liquid fraction

AU - Raufaste, Christophe

AU - Dollet, Benjamin

AU - Cox, Simon

AU - Jiang, Yi

AU - Graner, François

N1 - Raufaste, C., Dollet, B., Cox, S., Jiang, Y. and Graner, F. (2007). Yield drag in a
two-dimensional foam flow around a circular obstacle: Effect of liquid fraction.
European Physical Journal E, 23 (2), 217–228
Sponsorship: Y.J. is supported by US DOE under contract
No. DE-AC52-06NA25396. S.C. is supported by EPSRC (EP/D071127/1)

PY - 2007/6

Y1 - 2007/6

N2 - We study the two-dimensional flow of foams around a circular obstacle within a long channel. In
experiments, we confine the foam between liquid and glass surfaces. In simulations, we use a deterministic
software, the Surface Evolver, for bubble details and a stochastic one, the extended Potts model, for
statistics. We adopt a coherent definition of liquid fraction for all studied systems. We vary it in both
experiments and simulations, and determine the yield drag of the foam, that is, the force exerted on the
obstacle by the foam flowing at very low velocity. We find that the yield drag is linear over a large range of
the ratio of obstacle to bubble size, and is independent of the channel width over a large range. Decreasing
the liquid fraction, however, strongly increases the yield drag; we discuss and interpret this dependence.

AB - We study the two-dimensional flow of foams around a circular obstacle within a long channel. In
experiments, we confine the foam between liquid and glass surfaces. In simulations, we use a deterministic
software, the Surface Evolver, for bubble details and a stochastic one, the extended Potts model, for
statistics. We adopt a coherent definition of liquid fraction for all studied systems. We vary it in both
experiments and simulations, and determine the yield drag of the foam, that is, the force exerted on the
obstacle by the foam flowing at very low velocity. We find that the yield drag is linear over a large range of
the ratio of obstacle to bubble size, and is independent of the channel width over a large range. Decreasing
the liquid fraction, however, strongly increases the yield drag; we discuss and interpret this dependence.

U2 - 10.1140/epje/i2006-10178-9

DO - 10.1140/epje/i2006-10178-9

M3 - Article

C2 - 17619820

SN - 1292-8941

VL - 23

SP - 217

EP - 228

JO - European Physical Journal E

JF - European Physical Journal E

IS - 2

ER -