Slippery questions about complex fluids flowing past solids

Slippery questions about complex fluids flowing past solids

Authors: Steve Granick, Yingxi Zhu and Hyungjung Lee

Soft matter keywords

Rough surfaces, slip control, hydrophobicity

By Alex Epstein

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Abstract from the original paper

Viscous flow is familiar and useful, yet the underlying physics is surprisingly subtle and complex. Recent experiments and simulations show that the textbook assumption of ‘no slip at the boundary’ can fail greatly when walls are sufficiently smooth. The reasons for this seem to involve materials chemistry interactions that can be controlled — especially wettability and the presence of trace impurities, even of dissolved gases. To discover what boundary condition is appropriate for solving continuum equations requires investigation of microscopic particulars. Here, we draw attention to unresolved topics of investigation and to the potential to capitalize on ‘slip at the wall’ for purposes of materials engineering.

Soft matters

• • • I'm finishing reading the paper, which is fascinating. This wiki will be done end of Sunday.***

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References

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