Quantification of Coherent Structures in the Atmospheric Boundary Layer
Author : Felicity Mary Perry
Publisher :
Page : pages
File Size : 12,64 MB
Release : 2008
Category :
ISBN :
Qualification of Coherent Structures in the Atmospheric Boundary Layer
Author : Felicity Mary Perry
Publisher :
Page : 390 pages
File Size : 41,92 MB
Release : 2008
Category :
ISBN :
Book Description
Characterizing Turbulent Coherent Structures in the Atmospheric Surface Layer Using Integrated Quadrant Analysis
Author : Mary Rose Mangan
Publisher :
Page : 0 pages
File Size : 29,77 MB
Release : 2020
Category :
ISBN :
Book Description
Integrated quadrant analysis is a novel technique to characterize the trajectory and strength of turbulent coherent structures in the atmospheric surface layer. By integrating the three-dimensional velocity field characterized by traditional quadrant analysis with respect to time, the trajectory history of individual coherent structures can be preserved with Eulerian turbulence measurements. We developed a method to identify the ejection phase of coherent structures based on turbulent kinetic energy (TKE). Identifying coherent structures using TKE preforms better than identifying them with the only streamwise and vertical velocity components because some coherent structures are strongly linked to the cross-stream velocity. By combining this identification method with integrated quadrant analysis, one can animate or plot the trajectory of individual coherent structures. This procedure connects a coherent ejection with the subsequent sweep and quiescent period in time to visualize and quantify the strength and the duration of a coherent structure. We developed and verified the method of integrated quadrant analysis with data from three field studies: the Eclipse Boundary Layer Experiment (EBLE) in Corvallis, OR in August 2017, the Vertical Cherry Array Experiment (VACE) in Linden, CA in November 2019 and the Canopy Horizontal Array Turbulence Study (CHATS) in Dixon, CA in the spring of 2007. Integrated quadrant analysis is a promising addition to traditional turbulence analysis techniques because it provides information about an individual coherent structure that consists of both an ejection and a sweep attached to each other in a single sequence. The integrated analysis also helps to portray an eddy trajectory in three-dimensions around a sensor, which indicates that the turbulent cross-stream velocity is usually an important momentum transport component in a coherent structure. In the VACE and CHATS experiments, there is a plane of preferred eddy trajectory for each individual coherent structure. The plane depends on the component of the double headed hairpin vortex that the sensor measures.
Atmospheric Boundary Layer Flows
Author : J. C. Kaimal
Publisher : Oxford University Press
Page : 304 pages
File Size : 25,62 MB
Release : 1994-01-06
Category : Science
ISBN : 0195362772
Book Description
Boundary layer meteorology is the study of the physical processes that take place in the layer of air that is most influenced by the earth's underlying surface. This text/reference gives an uncomplicated view of the structure of the boundary layer, the instruments available for measuring its mean and turbulent properties, how best to make the measurements, and ways to process and analyze the data. The main applications of the book are in atmospheric modelling, wind engineering, air pollution, and agricultural meteorology. The authors have pioneered research on atmospheric turbulence and flow, and are noted for their contributions to the study of the boundary layer. This important work will interest atmospheric scientists, meteorologists, and students and faculty in these fields.
Frontiers in Turbulence and Coherent Structures
Author : J. P. Denier
Publisher : World Scientific
Page : 501 pages
File Size : 32,33 MB
Release : 2007
Category : Science
ISBN : 9812703934
Book Description
The Chickasaw Nation, an American Indian nation headquartered in southeastern Oklahoma, entered into a period of substantial growth in the late 1980s. Following its successful reorganization and expansion, which was enabled by federal policies for tribal self-determination, the Nation pursued gaming and other industries to affect economic growth. From 1987 to 2009 the Nation's budget increased exponentially as tribal investments produced increasingly large revenues for a growing Chickasaw population. Coincident to this growth, the Chickasaw Nation began acquiring and creating museums and heritage properties to interpret their own history, heritage, and culture through diverse exhibitionary representations. By 2009, the Chickasaw Nation directed representation of itself at five museum and heritage properties throughout its historic boundaries. Josh Gorman examines the history of these sites and argues that the Chickasaw Nation is using museums and heritage sites as places to define itself as a coherent and legitimate contemporary Indian nation. In doing so, they are necessarily engaging with the shifting historiographical paradigms as well as changing articulations of how museums function and what they represent. The roles of the Chickasaw Nation's museums and heritage sites in defining and creating discursive representations of sovereignty are examined within their historicized local contexts. The work describes the museum exhibitions' dialogue with the historiography of the Chickasaw Nation, the literature of new museum studies, and the indigenous exhibitionary grammars emerging from indigenous museums throughout the United States and the world.
Turbulent Shear Flows 5
Author : Franz Durst
Publisher : Springer Science & Business Media
Page : 367 pages
File Size : 11,38 MB
Release : 2012-12-06
Category : Science
ISBN : 3642714358
Book Description
The first four symposia in the series on turbulent shear flows have been held alternately in the United States and Europe with the first and third being held at universities in eastern and western States, respectively. Continuing this pattern, the Fifth Symposium on Turbulent Shear Flows was held at Cornell University, Ithaca, New York, in August 1985. The meeting brought together more than 250 participants from around the world to present the results of new research on turbulent shear flows. It also provided a forum for lively discussions on the implications (practical or academic) of some of the papers. Nearly 100 formal papers and about 20 shorter communications in open forums were presented. In all the areas covered, the meeting helped to underline the vitality of current research into turbulent shear flows whether in experimental, theoretical or numerical studies. The present volume contains 25 of the original symposium presentations. All have been further reviewed and edited and several have been considerably extended since their first presentation. The editors believe that the selection provides papers of archival value that, at the same time, give a representative statement of current research in the four areas covered by this book: - Homogeneous and Simple Flows - Free Flows - Wall Flows - Reacting Flows Each of these sections begins with an introductory article by a distinguished worker in the field.
Coherent Vortical Structures in the Atmospheric Boundary Layer Near Ground
Author : Ford Cropley
Publisher :
Page : pages
File Size : 33,73 MB
Release : 1990
Category :
ISBN :
Book Description
The Atmospheric Boundary Layer for Engineers
Author : R. S. Azad
Publisher : Springer Science & Business Media
Page : 600 pages
File Size : 27,33 MB
Release : 1993-03-31
Category : Technology & Engineering
ISBN : 9780792321873
Book Description
While I was participating in the IUTAM Symposium on Structure of Turbulence and Drag Reduction in Zurich, Switzerland, in 1989, I was approached by Prof. Dr. Themistocles Dracos to give a course oflectures on the Atmospheric Boundary Layer during my sabbatical leave at Eidgenossische Technische Hochschule (ETH) Zurich - Hoenggerberg in 1991. His reason for the suggestion was the growing interest in the environment and its dynamics created by flow in the Atmospheric Boundary Layer. I have been teaching boundary layer to undergraduate and graduate students for more than twenty five years, so I agreed to give a series of lectures on boundary layer of the atmosphere. From the start I thought very seriously about the problem and consulted all the published works in English on the Atmospheric Boundary Layer (ABL). First consider the topography of the Earth which has oceans calm and turbulent, mountain ranges of height up to 9 km, lands of variable height with forests, food growing vegetable and deserts. The shape of the Earth is nearly spherical except at the north and south poles. Sun supplies the energy to drive circulation of air around the Earth's atmosphere which for all practical purposes occupies the region up to about 10 to 11 km. This brief scenerio of Earth's topography reveals the complexity of flow very close to the Earth's surface that is hardly flat except at the oceans' surface which consists of about 70% of the total Earth's surface.
Texture Feature Extraction Techniques for Image Recognition
Author : Jyotismita Chaki
Publisher : Springer Nature
Page : 100 pages
File Size : 26,53 MB
Release : 2019-10-24
Category : Technology & Engineering
ISBN : 9811508534
Book Description
The book describes various texture feature extraction approaches and texture analysis applications. It introduces and discusses the importance of texture features, and describes various types of texture features like statistical, structural, signal-processed and model-based. It also covers applications related to texture features, such as facial imaging. It is a valuable resource for machine vision researchers and practitioners in different application areas.
The Atmospheric Boundary Layer
Author : J. R. Garratt
Publisher : Cambridge University Press
Page : 340 pages
File Size : 36,28 MB
Release : 1994-04-21
Category : Mathematics
ISBN : 9780521467452
Book Description
The book gives a comprehensive and lucid account of the science of the atmospheric boundary layer (ABL). There is an emphasis on the application of the ABL to numerical modelling of the climate. The book comprises nine chapters, several appendices (data tables, information sources, physical constants) and an extensive reference list. Chapter 1 serves as an introduction, with chapters 2 and 3 dealing with the development of mean and turbulence equations, and the many scaling laws and theories that are the cornerstone of any serious ABL treatment. Modelling of the ABL is crucially dependent for its realism on the surface boundary conditions, and chapters 4 and 5 deal with aerodynamic and energy considerations, with attention to both dry and wet land surfaces and sea. The structure of the clear-sky, thermally stratified ABL is treated in chapter 6, including the convective and stable cases over homogeneous land, the marine ABL and the internal boundary layer at the coastline. Chapter 7 then extends the discussion to the cloudy ABL. This is seen as particularly relevant, since the extensive stratocumulus regions over the subtropical oceans and stratus regions over the Arctic are now identified as key players in the climate system. Finally, chapters 8 and 9 bring much of the book's material together in a discussion of appropriate ABL and surface parameterization schemes in general circulation models of the atmosphere that are being used for climate simulation.
