Effective slippage on superhydrophobic trapezoidal grooves

Abstract

We study the effective slippage on superhydrophobic grooves with trapezoidal cross-sections of various geometries (including the limiting cases of triangles and rectangular stripes), by using two complementary approaches. First, dissipative particle dynamics (DPD) simulations of a flow past such surfaces have been performed to validate an expression [E. S. Asmolov and O. I. Vinogradova, J. Fluid Mech. 706, 108 (2012)] that relates the eigenvalues of the effective slip-length tensor for one-dimensional textures. Second, we propose theoretical estimates for the effective slip length and calculate it numerically by solving the Stokes equation based on a collocation method. The comparison between the two approaches shows that they are in excellent agreement. Our results demonstrate that the effective slippage depends strongly on the area-averaged slip, the amplitude of the roughness, and on the fraction of solid in contact with the liquid. To interpret these results, we analyze flow singularities near slipping heterogeneities, and demonstrate that they inhibit the effective slip and enhance the anisotropy of the flow. Finally, we propose some guidelines to design optimal one-dimensional superhydrophobic surfaces, motivated by potential applications in microfluidics.

Autoren

Jiajia Zhou
Evgeny S Asmolov
Friederike Schmid
Olga I Vinogradova

DOI

10.1063/1.4827867

eISSN

1089-7690

ISSN

0021-9606

Ausgabe der Veröffentlichung

17

Zeitschrift

The Journal of Chemical Physics

Sprache

en

Online publication date

2013

Datum der Veröffentlichung

2013

Status

Published

Herausgeber

AIP Publishing

Herausgeber URL

http://dx.doi.org/10.1063/1.4827867

Datum der Datenerfassung

2023

Titel

Effective slippage on superhydrophobic trapezoidal grooves

Ausgabe der Zeitschrift

139

Data source: Crossref

Abstract

We study the effective slippage on superhydrophobic grooves with trapezoidal cross-sections of various geometries (including the limiting cases of triangles and rectangular stripes), by using two complementary approaches. First, dissipative particle dynamics (DPD) simulations of a flow past such surfaces have been performed to validate an expression [E. S. Asmolov and O. I. Vinogradova, J. Fluid Mech. 706, 108 (2012)] that relates the eigenvalues of the effective slip-length tensor for one-dimensional textures. Second, we propose theoretical estimates for the effective slip length and calculate it numerically by solving the Stokes equation based on a collocation method. The comparison between the two approaches shows that they are in excellent agreement. Our results demonstrate that the effective slippage depends strongly on the area-averaged slip, the amplitude of the roughness, and on the fraction of solid in contact with the liquid. To interpret these results, we analyze flow singularities near slipping heterogeneities, and demonstrate that they inhibit the effective slip and enhance the anisotropy of the flow. Finally, we propose some guidelines to design optimal one-dimensional superhydrophobic surfaces, motivated by potential applications in microfluidics.

Addresses

Institut für Physik, Johannes Gutenberg-Universität Mainz, D55099 Mainz, Germany.

Autoren

Jiajia Zhou
Evgeny S Asmolov
Friederike Schmid
Olga I Vinogradova

DOI

10.1063/1.4827867

eISSN

1089-7690

Externe Identifier

PubMed Identifier: 24206323

Open access

false

ISSN

0021-9606

Ausgabe der Veröffentlichung

17

Zeitschrift

The Journal of chemical physics

Sprache

eng

Medium

Print

Paginierung

174708

Datum der Veröffentlichung

2013

Status

Published

Datum der Datenerfassung

2013

Titel

Effective slippage on superhydrophobic trapezoidal grooves.

Sub types

Journal Article

Ausgabe der Zeitschrift

139

Data source: Europe PubMed Central

Abstract

We study the effective slippage on superhydrophobic grooves with trapezoidal cross-sections of various geometries (including the limiting cases of triangles and rectangular stripes), by using two complementary approaches. First, dissipative particle dynamics (DPD) simulations of a flow past such surfaces have been performed to validate an expression [E. S. Asmolov and O. I. Vinogradova, J. Fluid Mech. 706, 108 (2012)] that relates the eigenvalues of the effective slip-length tensor for one-dimensional textures. Second, we propose theoretical estimates for the effective slip length and calculate it numerically by solving the Stokes equation based on a collocation method. The comparison between the two approaches shows that they are in excellent agreement. Our results demonstrate that the effective slippage depends strongly on the area-averaged slip, the amplitude of the roughness, and on the fraction of solid in contact with the liquid. To interpret these results, we analyze flow singularities near slipping heterogeneities, and demonstrate that they inhibit the effective slip and enhance the anisotropy of the flow. Finally, we propose some guidelines to design optimal one-dimensional superhydrophobic surfaces, motivated by potential applications in microfluidics.

Autoren

Jiajia Zhou
Evgeny S Asmolov
Friederike Schmid
Olga I Vinogradova

Autoren-URL

https://www.ncbi.nlm.nih.gov/pubmed/24206323

DOI

10.1063/1.4827867

eISSN

1089-7690

Ausgabe der Veröffentlichung

17

Zeitschrift

J Chem Phys

Sprache

eng

Country

United States

Paginierung

174708

Datum der Veröffentlichung

2013

Status

Published

Datum, an dem der Datensatz öffentlich gemacht wurde

2014

Titel

Effective slippage on superhydrophobic trapezoidal grooves.

Sub types

Journal Article

Ausgabe der Zeitschrift

139

Data source: PubMed

Effective slippage on superhydrophobic trapezoidal grooves

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