TY - JOUR
T1 - Thin-film fluid flows over microdecorated surfaces
T2 - Observation of polygonal hydraulic jumps
AU - Dressaire, Emilie
AU - Courbin, Laurent
AU - Crest, Jérome
AU - Stone, Howard A.
PY - 2009/5/11
Y1 - 2009/5/11
N2 - Liquid films flowing over rough substrates are influenced by asperities whose sizes are comparable to the film thickness. We investigate flows driven by jet impact on a regular array of micron-size posts. We show that the topography modifies the size and the shape of the observed hydraulic jumps: in addition to circular jumps, we obtain a variety of stable polygonal shapes. We rationalize our results by considering a leakage flow through the texture and the free-surface flow above it, coupled by an effective slip boundary condition accounting for the symmetry of the texture. This model is in good agreement with our experiments and allows us to account for the interplay between flow properties and roughness parameters, which has applicability in many other thin-film configurations.
AB - Liquid films flowing over rough substrates are influenced by asperities whose sizes are comparable to the film thickness. We investigate flows driven by jet impact on a regular array of micron-size posts. We show that the topography modifies the size and the shape of the observed hydraulic jumps: in addition to circular jumps, we obtain a variety of stable polygonal shapes. We rationalize our results by considering a leakage flow through the texture and the free-surface flow above it, coupled by an effective slip boundary condition accounting for the symmetry of the texture. This model is in good agreement with our experiments and allows us to account for the interplay between flow properties and roughness parameters, which has applicability in many other thin-film configurations.
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U2 - 10.1103/PhysRevLett.102.194503
DO - 10.1103/PhysRevLett.102.194503
M3 - Article
C2 - 19518960
AN - SCOPUS:65649100525
SN - 0031-9007
VL - 102
JO - Physical review letters
JF - Physical review letters
IS - 19
M1 - 194503
ER -