title: Flow past superhydrophobic surfaces with cosine variation in local slip length.
abstract: Anisotropic superhydrophobic surfaces have the potential to greatly reduce drag and enhance mixing phenomena in microfluidic devices. Recent work has focused mostly on cases of superhydrophobic stripes. Here, we analyze a relevant situation of cosine variation of the local slip length. We derive approximate formulas for maximal (longitudinal) and minimal (transverse) directional effective slip lengths that are in good agreement with the exact numerical solution and lattice-Boltzmann simulations. Compared to the case of superhydrophobic stripes, the cosine texture can provide a very large effective slip. However, the difference between eigenvalues of the slip-length tensor is smaller, indicating that the flow is less anisotropic.
authors.affiliation: A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky Prospect, 119071 Moscow, Russia.
authors.forename: Evgeny S
authors.initials: ES
authors.lastname: Asmolov
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schmieschek
authors.forename: Jens
authors.initials: J
authors.lastname: Harting
authors.forename: Olga I
authors.initials: OI
authors.lastname: Vinogradova
mesh_terms: D003198:Computer Simulation; D057927:Hydrophobic and Hydrophilic Interactions; D044085:Microfluidics / Q000379:methods*; D008962:Models, Theoretical; D012996:Solutions / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012996:Solutions