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Transitional Shear Layers on Rectangular Sections

  • D. M. MooreEmail author
  • C. W. Letchford
  • M. Amitay
Conference paper
Part of the Lecture Notes in Civil Engineering book series (LNCE, volume 27)

Abstract

The present work implements 2D Particle Image Velocimetry measurements in an effort to study the transition process of the separated shear layer on rectangular sections. Inspection of the average and fluctuating vector fields enable quantitative definitions of important length scales such as transition lengths and reattachment lengths. The effect of free stream Reynolds number is examined in detail which, among other points, show clear trends of increasingly rapid transitions lengths over the wind speeds investigated. Additionally, transitional shear layer dynamics are discussed for sections exposed to inclined winds. It is shown that under small angles of attack, relatively large changes in shear layer trajectory result in significant alterations to the global loads felt by the body.

Keywords

Bluff body Shear layer Transition Turbulence 

Notes

Acknowledgements

Portions of this work are gratefully supported through the National Science Foundation under grant number 1727401.

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Mechanical, Aerospace and Nuclear EngineeringRensselaer Polytechnic InstituteTroyUSA
  2. 2.Department of Civil and Environmental EngineeringRensselaer Polytechnic InstituteTroyUSA

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