Coherent Flow Structures at Earth’s Surface

An expert review of recent progress in the study of turbulent flows with a focus on recently identified organized structures. This book reviews the recent progress in the study of the turbulent flows that sculpt the Earth s surface, focusing in particular on the organized structures that have been identified in recent years within turbulent flows. These coherent flow structures can include eddies or vortices at the scale of individual grains, through structures that scale with the flow depth in rivers or estuaries, to the large-scale structure of flows at the morphological or landform scale. These flow structures are of wide interest to the scientific community because they play an important role in fluid dynamics and influence the transport, erosion and deposition of sediment and pollutants in a wide variety of fluid flow environments. Scientific knowledge of these structures has improved greatly over the past 20 years as computational fluid dynamics has come to play an increasing important part in building our understanding of coherent flow structures across a broad range of scales. Chapters comprise a series of major, invited papers and a selection of the most novel, innovative papers presented at the second Coherent Flow Structures Conference held August 3-5, 2011 at Simon Fraser University in Burnaby, British Columbia. Chapters focus on six major themes: Dynamics of coherent flow structures (CFS) in geophysical flows Interaction of turbulent flows, vegetation and ecological habitats Coherent structure of atmospheric flows Numerical modeling of coherent flow structures Turbulence in open channel flows Coherent flow structures, sediment transport and morphological feedbacks.

An expert review of recent progress in the study of turbulentflows with a focus on recently identified organizedstructures.This book reviews the recent progress in the study of the turbulentflows that sculpt the Earth's surface, focusing inparticular on the organized structures that have been identified inrecent years within turbulent flows. These coherent flowstructures can include eddies or vortices at the scale ofindividual grains, through structures that scale with the flowdepth in rivers or estuaries, to the large-scale structure of flowsat the morphological or landform scale. These flow structuresare of wide interest to the scientific community because they playan important role in fluid dynamics and influence thetransport, erosion and deposition of sediment andpollutants in a wide variety of fluid flowenvironments.Scientific knowledge of these structures has improved greatlyover the past 20 years as computational fluid dynamics hascome to play an increasing important part in building ourunderstanding of coherent flow structures across a broad rangeof scales.Chapters comprise a series of major, invited papers and aselection of the most novel, innovative papers presented atthe second Coherent Flow Structures Conference held August 3-52011 at Simon Fraser University in Burnaby, BritishColumbia.Chapters focus on six major themes:* Dynamics of coherent flow structures (CFS) in geophysicalflows* Interaction of turbulent flows, vegetation and ecologicalhabitats* Coherent structure of atmospheric flows* Numerical modeling of coherent flow structures* Turbulence in open channel flows* Coherent flow structures, sediment transport and morphologicalfeedbacks.

List of Contributors, viiPreface, xiAbout the Companion Website, xiii1 What is a Coherent Flow Structure in Geophysical Flow? 1Jeremy G. Venditti, Richard J. Hardy, Michael Church, & James L. Best2 Structure of Turbulent Boundary Layers 17Ronald J. Adrian3 Structural Attributes of Turbulent Flow over a Complex Topography 25Ricardo Mejia-Alvarez, Julio M. Barros, & Kenneth T. Christensen4 Coherent Flow Structures in the Pore Spaces of Permeable Beds underlying a Unidirectional Turbulent Boundary Layer: A Review and some New Experimental Results 43Gianluca Blois, James L. Best, Kenneth T. Christensen, Richard J. Hardy, & Gregory H. Sambrook Smith5 Instabilities in Stratified Shear Flow 63Gregory A. Lawrence, Edmund W. Tedford, & Jeffrey R. Carpenter6 Scalar Turbulence within the Canopy Sublayer 73Gabriel G. Katul, Daniela Cava, Mario Siqueira, & Davide Poggi7 On the Structure of Wall Turbulence in the Thermally Neutral Atmospheric Surface Layer 97Michele Guala, Jeff LeHew, Meredith Metzger, & Beverley J. McKeon8 Critical Reflections on the Coherent Flow Structures Paradigm in Aeolian Geomorphology 111Bernard O. Bauer, Ian J. Walker, Andreas C.W. Baas, Derek W.T. Jackson, Cheryl McKenna Neuman, Giles F.S. Wiggs, & Patrick A. Hesp9 Coherent Flow Structures in Vegetated Channels 135Heidi Nepf, Jeffrey Rominger, & Lijun Zong10 Coherent Eddy Structures over Plant Canopies 149Roger H. Shaw, Edward G. Patton, & John J. Finnigan11 SPIV Analysis of Coherent Structures in a Vegetation Canopy Model Flow 161Laurent Perret & Tony Ruiz