Full Program »

Turbulent flow over superhydrophobic surfaces - roughness versus slip

PDF
0.4MB

Superhydrophobic surfaces have the potential to reduce drag both in the laminar and turbulent regimes. However, the slip at the air-water interface can be adversely affected by the roughness of the structure of the surface which is needed to support the air layer. The conflicting effects of roughness and slip are investigated by direct numerical simulations of turbulent channel flow over patterned slip - no-slip surfaces. It is found that even a relatively small exposed roughness height can counteract the drag reducing effects of the slip at an air-water interface.

Author(s):

Angela Busse    
University of Southampton
United Kingdom

Neil Sandham    
University of Southampton
United Kingdom