Encyclopedia of Nanotechnology

2012 Edition
| Editors: Bharat Bhushan

Shark Skin Drag Reduction

Reference work entry
DOI: https://doi.org/10.1007/978-90-481-9751-4_266



The scales, or denticles, on fast-swimming sharks have evolved two mechanisms for controlling the boundary layer flow over the skin surface leading to a reduction in drag. The first, and most widely known and studied, consists of the small streamwise keels covering the surface of the scales also known as riblets which reduce turbulent skin friction drag. The second mechanism is attributed to loosely embedded scales that are located on key regions of the body. When actuated to bristle by the flow, these scales potentially act as a means of controlling flow separation, thereby minimizing pressure drag during swimming maneuvers. Shark scales display a wide variation in geometry both across species while also varying with body location, but on faster swimming sharks, they typically range in size from 180 to 500 μm in crown length.


The Shark Skin

Sharks are covered with minute scales, also known as...
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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of Aerospace Engineering & MechanicsUniversity of AlabamaTuscaloosaUSA
  2. 2.Department of Integrative BiologyUniversity of South FloridaTampaUSA