Download or read book Coherent structures and secondary motions in open duct flow written by Sakai, Yoshiyuki and published by KIT Scientific Publishing. This book was released on 2019-08-22 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coherent Structures and Secondary Motions in Open Duct Flow written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent coherent structures Secondary currents and Sediment ridges written by Scherer, Markus Maximilian and published by KIT Scientific Publishing. This book was released on 2024-06-19 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: The origin of secondary currents and subaqueous sediment patterns in natural rivers is analysed from first principles. For this purpose, simulations of sediment transport in canonical turbulent open channel flows are performed using a numerical technique that resolves all relevant flow scales and the dynamics of the individual sand grains. The high-fidelity datasets reveal the fundamental importance of individual coherent structures for the development of sediment patterns and secondary flows.
Download or read book River Flow 2020 written by Wim Uijttewaal and published by CRC Press. This book was released on 2020-08-27 with total page 2459 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rivers form one of the lifelines in our society by providing essential services such as availability of fresh water, navigation, energy, ecosystem services, and flood conveyance. Because of this essential role, mankind has interfered continuously in order to benefit most and at the same time avoid adverse consequences such as flood risk and droughts. This has resulted in often highly engineered rivers with a narrow set of functions. In the last decades rivers are increasingly considered in a more holistic manner as a system with a multitude of interdependent processes. River research and engineering has therefore added to the river fundamentals also themes like ecohydraulics, consequences of climate change, and urbanisation. River Flow 2020 contains the contributions presented at the 10th conference on Fluvial Hydraulics, River Flow 2020, organised under the auspices of the Committee on Fluvial Hydraulics of the International Association for Hydro-Environment Engineering and Research (IAHR). What should have been a lively physical gathering of researchers, students and practitioners, was converted into an online event as the COVID-19 pandemic hindered international travelling and large gatherings of people. Nevertheless, the fluvial hydraulics community showed their interest and to be very much alive with a high number of participations for such event. Since its first edition in 2002, in Louvain-la-Neuve, this series of conferences has found a large and loyal audience in the river research and engineering community while being also attractive to the new researchers and young professionals. This is highlighted by the large number of contributions applying for the Coleman award for young researchers, and also by the number of applications and attendants to the Master Classes which are aimed at young researchers and students. River Flow 2020 aims to provide an updated overview of the ongoing research in this wide range of topics, and contains five major themes which are focus of research in the fluvial environment: river fundamentals, the digital river, the healthy river, extreme events and rivers under pressure. Other highlights of River Flow 2020 include the substantial number of interdisciplinary subthemes and sessions of special interest. The contributions will therefore be of interest to academics in hydraulics, hydrology and environmental engineering as well as practitioners that would like to be updated about the newest findings and hot themes in river research and engineering.
Download or read book A hydrodynamical perspective on the turbulent transport of bacteria in rivers written by Krayer, Michael Werner Tobias and published by KIT Scientific Publishing. This book was released on 2023-09-11 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: The transport of bacteria in turbulent river-like environments is addressed, where bacterial populations are frequently encountered attached to solids. This transport mode is investigated by studying the transient settling of heavy particles in turbulent channel flows featuring sediment beds. A numerical method is used to fully resolve turbulence and finite-size particles, which enables the assessment of the complex interplay between flow structures, suspended solids and river sediment.
Download or read book High Performance Computing in Science and Engineering 15 written by Wolfgang E. Nagel and published by Springer. This book was released on 2016-02-05 with total page 701 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS) in 2015. The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and engineers. The book comes with a wealth of color illustrations and tables of results.
Download or read book Turbulence in Open Channel Flows written by Hiroji Nakagawa and published by Routledge. This book was released on 2017-10-02 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of open channel turbulence, focusing especially on certain features stemming from the presence of the free surface and the bed of a river. Part one presents the statistical theory of turbulence; Part two addresses the coherent structures in open-channel flows and boundary layers.
Download or read book Handbook of Environmental Fluid Dynamics Two Volume Set written by Harindra Joseph Fernando and published by CRC Press. This book was released on 2012-12-11 with total page 1222 pages. Available in PDF, EPUB and Kindle. Book excerpt: With major implications for applied physics, engineering, and the natural and social sciences, the rapidly growing area of environmental fluid dynamics focuses on the interactions of human activities, environment, and fluid motion. A landmark for the field, this two-volume Handbook of Environmental Fluid Dynamics presents the basic principles, fund
Download or read book Direct Numerical Simulation of Very Large Scale Motions in Turbulent Pipe Flow written by Christian Bauer and published by Cuvillier Verlag. This book was released on 2021-02-01 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Die turbulente Rohrströmung ist nicht nur von großer Bedeutung für Anwendungen im Ingenieurbereich, sondern auch für die Grundlagenforschung von wandnaher Turbulenz. In der vorliegenden Arbeit wird die Interaktion sogenannter turbulenter Superstrukturen (engl.: very-large-scale motions, VLSMs) mit der kleinskaligen Wandturbulenz auf Basis der Methode der direkten numerischen Simulation untersucht. Dabei werden Schubspannungs-Reynoldszahlen bis Reτ = 2880 und Rohrlängen bis L = 42R berücksichtigt. Es wird das Konvergenz- und Skalierungsverhalten verschiedener statistischer Momente der Geschwindigkeitsverteilung untersucht und in Bezug auf VLSMs diskutiert. Die folgende Analyse der axialen Energietransportgleichung des gefilterten Geschwindigkeitsfeldes legt offen, dass VLSMs Energie von der mittleren Strömung zugeführt bekommen, ähnlich den kleinskaligen Strukturen durch den turbulenten Produktionsmechanismus. Die verschiedenen Terme der Energiebilanz werden sowohl anhand von mittleren Profilen, als auch instantanen Strömungsvisualisierungen und drei-dimensionalen Korrelationen diskutiert, wobei auch auf das Phänomen der inversen turbulenten Energiekaskade eingegangen wird. Die Forschungsarbeit gewährt dabei neue Einblicke in die Interaktion der VLSMs mit dem turbulenten Wandzyklus und trägt zum besseren Verständnis der turbulenten Rohrströmung bei. Turbulent pipe flow is not only of importance to engineering applications but also of fundamental interest to the study of wall-bounded turbulence. In the present work, the interaction of the so-called very-large-scale motions (VLSMs) with the near-wall, small-scale turbulence is explored by means of direct numerical simulation for friction Reynolds numbers up to Reτ = 2880 and pipe lengths up to L = 42R. Besides, the convergence and the scaling of different order moments of the velocity distribution are studied and also discussed with regard to VLSMs. The subsequent analysis of the streamwise energy budget equation of the filtered velocity field reveals that VLSMs obtain their energy from the mean velocity field via a production mechanism similar to the one known from the near-wall cycle. Moreover, the different energy budget terms are investigated by means of statistical averages, instantaneous flow field visualisations, and three-dimensional correlations, wherein the backscattering phenomenon is also dealt with. In brief, the research sheds new light on our understanding of the interaction between VLSMs and the near-wall cycle and leads to a better grasp of turbulent pipe flow in general.
Download or read book Turbulence and Flow Sediment Interactions in Open Channel Flows written by Roberto Gaudio and published by MDPI. This book was released on 2021-06-04 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main focus of this Special Issue of Water is the state-of-the-art and recent research on turbulence and flow–sediment interactions in open-channel flows. Our knowledge of river hydraulics is deepening, thanks to both laboratory/field experiments related to the characteristics of turbulence and their link to erosion, transport, deposition, and local scouring phenomena. Collaboration among engineers, physicists, and other experts is increasing and furnishing new inter-/multidisciplinary perspectives to the research of river hydraulics and fluid mechanics. At the same time, the development of both sophisticated laboratory instrumentation and computing skills is giving rise to excellent experimental–numerical comparative studies. Thus, this Special Issue, with ten papers by researchers from many institutions around the world, aims at offering a modern panoramic view on all the above aspects to the vast audience of river researchers.
Download or read book Water Resources Research Progress written by Liam N. Robinson and published by Nova Publishers. This book was released on 2008 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water resources are sources of water that are useful or potentially useful to humans. They are important because they are needed for life to exist. Many uses of water include agricultural, industrial, household, recreational and environmental activities. Virtually all of these human uses require fresh water. Only 2.7% of water on the Earth is fresh water, and over two thirds of this is frozen in glaciers and polar ice caps, leaving only 0.007% available for human use. Fresh water is a renewable resource, yet the world's supply of clean, fresh water is steadily decreasing. Water demand already exceeds supply in many parts of the world, and as world population continues to rise at an unprecedented rate, many more areas are expected to experience this imbalance in the near future. The framework for allocating water resources to water users (where such a framework exists) is known as water rights. This new book presents recent and important research in the field.
Download or read book Intermittency and Self Organisation in Turbulence and Statistical Mechanics written by Eun-jin Kim and published by MDPI. This book was released on 2019-07-29 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue Intermittency and Self-Organisation in Turbulence and Statistical Mechanics that was published in Entropy
Download or read book Fluid Mechanics of Environmental Interfaces Second Edition written by Carlo Gualtieri and published by CRC Press. This book was released on 2012-11-21 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental Fluid Mechanics (EFM) studies the motion of air and water at several different scales, the fate and transport of species carried along by these fluids, and the interactions among those flows and geological, biological, and engineered systems. EFM emerged some decades ago as a response to the need for tools to study problems of flow and transport in rivers, estuaries, lakes, groundwater and the atmosphere; it is a topic of increasing importance for decision makers, engineers, and researchers alike. The second edition of the successful textbook "Fluid Mechanics of Environmental Interfaces" is still aimed at providing a comprehensive overview of fluid mechanical processes occurring at the different interfaces existing in the realm of EFM, such as the air-water interface, the air-land interface, the water-sediment interface, the surface water-groundwater interface, the water-vegetation interface, and the water-biological systems interface. Across any of these interfaces mass, momentum, and heat are exchanged through different fluid mechanical processes over various spatial and temporal scales. In this second edition, the unique feature of this book, considering all the topics from the point of view of the concept of environmental interface, was maintained while the chapters were updated and five new chapters have been added to significantly enlarge the coverage of the subject area. The book starts with a chapter introducing the concept of EFM and its scope, scales, processes and systems. Then, the book is structured in three parts with fifteen chapters. Part one, which is composed of four chapters, covers the processes occurring at the interfaces between the atmosphere and the surface of the land and the seas, including the transport of dust and the dispersion of passive substances within the atmosphere. Part two deals in five chapters with the fluid mechanics at the air-water interface at small scales and sediment-water interface, including the advective diffusion of air bubbles, the hyporheic exchange and the tidal bores. Finally, part three discusses in six chapters the processes at the interfaces between fluids and biotic systems, such as transport processes in the soil-vegetation-lower atmosphere system, turbulence and wind above and within the forest canopy, flow and mass transport in vegetated open channels, transport processes to and from benthic plants and animals and coupling between interacting environmental interfaces. Each chapter has an educational part, which is structured in four sections: a synopsis of the chapter, a list of keywords that the reader should have encountered in the chapter, a list of questions and a list of unsolved problems related to the topics covered by the chapter. The book will be of interest to graduate students and researchers in environmental sciences, civil engineering and environmental engineering, (geo)physics, atmospheric science, meteorology, limnology, oceanography, and applied mathematics.
Download or read book Physics Briefs written by and published by . This book was released on 1991 with total page 1454 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Techniques in Fluid Thermal and Combustion Flow written by and published by . This book was released on 1997 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances In Hydraulics And Water Engineering Volumes I Ii Proceedings Of The 13th Iahr apd Congress written by John Junke Guo and published by World Scientific. This book was released on 2002-07-18 with total page 1152 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a wide range of recent advances in hydraulics and water engineering. It contains four sections: hydraulics and open channel flow; hydrology, water resources management and hydroinformatics; maritime hydraulics; ecohydraulics and water quality management. World authorities such as Mike Abbot, I Nezu, A J Metha, M Garcia and P Y Julien have contributed to the book.
Download or read book Direct Numerical Simulation of Turbulent Flow and Heat Transfer in a Square Duct Roughened with Transverse Or V shaped Ribs written by Seyyed Vahid Mahmoodi Jezeh and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This integrated thesis documents a series of complementary numerical investigations aimed at an improved understanding of turbulent flows and heat transfer in a square duct with ribs of different shapes mounted on one wall. Direct numerical simulation (DNS) is used to accurately resolve the spatial and temporal scales of the simulated flows. The first DNS investigates the turbulent flow in a ribbed square duct of different blockage ratios. The results are compared with those of a smooth duct flow. It is observed that an augmentation of the blockage ratio concurrently generates stronger turbulent secondary flow motions, which drastically alter the turbulent transport processes between the sidewall and duct center, giving rise to high-degrees of non-equilibrium states. The dynamics of coherent structures are studied by examining characteristics of the instantaneous velocity field, swirling strength, spatial two-point auto-correlations, and velocity spectra. The impact of the blockage ratio on the turbulent heat transfer is investigated in the second numerical study. The results show that owing to the existence of the ribs and confinement of the duct, organized secondary flows appear as large streamwise-elongated vortices, which have profound influences on the transport of momentum and thermal energy. This study also shows that the spatial distribution and magnitude of the drag and heat transfer coefficients are highly sensitive to the rib height. The final study focuses on a comparison of highly-disturbed turbulent flows in a square duct with inclined and V-shaped ribs mounted on one wall. The turbulence field is highly sensitive to not only the rib geometry but also the boundary layers developed over the side and top walls. Owing to the difference in the pattern of the cross-stream secondary flow motions of these two ribbed duct cases, the flow physics in the inclined rib case is significantly different from the V-shaped rib case. It is found that near the leeward and windward faces of the ribs, the mean inclination angle of turbulence structures in the V-shaped rib case is greater than that of the inclined rib case, which subsequently enhances momentum transport between the ribbed bottom wall and the smooth top wall.
