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Effect of Irregular Surface in a Turbulent Channel

  • David Sassun
  • Paolo Orlandi
Conference paper
First Online:
Part of the Springer Proceedings in Physics book series (SPPHY, volume 165)

Abstract

The effect of highly irregular surfaces in a turbulent channel is studied through DNS through the use of the immersed boundary method to reproduce complex surfaces. The height of the surfaces analyzed is proportional to the streamwise velocity component u or the pressure p in a wall parallel plane of a smooth channel at \(y^+=12\). The surface with height proportional to u is drag reducing, that proportional to p is drag increasing. The relative magnitude of the friction components allows to identify the type of roughness as k-type, since the form drag is larger than the viscous drag. An additional surface has been obtained by smoothing a regular geometry made of staggered cubes. In this case, the resistance is doubled, and the form drag is much larger than the viscous drag.

Keywords

Turbulent Kinetic Energy Turbulent Viscosity Roughness Element Viscous Drag Immerse Boundary Method 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Dipartimento di Meccanica e AerospazialeSapienza Universitá di RomaRomeItaly

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