Recent experimental and computational investigations have shown that trace amounts of surfactants, unavoidable in practice, can critically impair the drag reduction of superhydrophobic surfaces (SHSs), by inducing Marangoni stresses at the air–liquid interface. However, predictive models for realistic SHS geometries do not yet exist, which has limited the understanding and mitigation of these adverse surfactant effects. To address this issue, we derive a model for laminar, three-dimensional flow over SHS gratings as a function of geometry and soluble surfactant properties, which together encompass 10 dimensionless groups. We establish that the grating length
- Award ID(s):
- 1801971
- NSF-PAR ID:
- 10232145
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 11
- Issue:
- 39
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 10647 to 10656
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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