Download or read book A general filter for stretched grid models written by Dorina Surcel and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Report Series on Global Modeling and Data Assimilation Volume 16 written by Lawrence L. Takacs and published by BiblioGov. This book was released on 2013-08 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the techniques used to filter quantities on a stretched grid general circulation model. Standard high-latitude filtering techniques (e.g., using an FFT (Fast Fourier Transformations) to decompose and filter unstable harmonics at selected latitudes) applied on a stretched grid are shown to produce significant distortions of the prognostic state when used to control instabilities near the pole. A new filtering technique is developed which accurately accounts for the non-uniform grid by computing the eigenvectors and eigenfrequencies associated with the stretching. A filter function, constructed to selectively damp those modes whose associated eigenfrequencies exceed some critical value, is used to construct a set of grid-spaced weights which are shown to effectively filter without distortion. Both offline and GCM (General Circulation Model) experiments are shown using the new filtering technique. Finally, a brief examination is also made on the impact of applying the Shapiro filter on the stretched grid.
Download or read book Filtering techniques on a stretched grid general circulation model written by Lawrence Takacs and published by . This book was released on 1999 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Techniques for Global Atmospheric Models written by Peter H. Lauritzen and published by Springer Science & Business Media. This book was released on 2011-03-29 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book surveys recent developments in numerical techniques for global atmospheric models. It is based upon a collection of lectures prepared by leading experts in the field. The chapters reveal the multitude of steps that determine the global atmospheric model design. They encompass the choice of the equation set, computational grids on the sphere, horizontal and vertical discretizations, time integration methods, filtering and diffusion mechanisms, conservation properties, tracer transport, and considerations for designing models for massively parallel computers. A reader interested in applied numerical methods but also the many facets of atmospheric modeling should find this book of particular relevance.
Download or read book Technical Report Series on Global Modeling and Data Assimilation Volume 16 Filtering Techniques on a Stretched Grid General Circulation Model written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-21 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the techniques used to filter quantities on a stretched grid general circulation model. Standard high-latitude filtering techniques (e.g., using an FFT (Fast Fourier Transformations) to decompose and filter unstable harmonics at selected latitudes) applied on a stretched grid are shown to produce significant distortions of the prognostic state when used to control instabilities near the pole. A new filtering technique is developed which accurately accounts for the non-uniform grid by computing the eigenvectors and eigenfrequencies associated with the stretching. A filter function, constructed to selectively damp those modes whose associated eigenfrequencies exceed some critical value, is used to construct a set of grid-spaced weights which are shown to effectively filter without distortion. Both offline and GCM (General Circulation Model) experiments are shown using the new filtering technique. Finally, a brief examination is also made on the impact of applying the Shapiro filter on the stretched grid.Takacs, Lawrence L. and Sawyer, William and Suarez, Max J. (Editor) and Fox-Rabinowitz, Michael S.Goddard Space Flight CenterATMOSPHERIC GENERAL CIRCULATION MODELS; ASSIMILATION; MATHEMATICAL MODELS; SPATIAL FILTERING; DATA INTEGRATION; COMPUTATIONAL GRIDS; STABILITY; GEOS SATELLITES (ESA); EIGENVECTORS; NONUNIFORMITY; FAST FOURIER TRANSFORMATIONS; POLAR REGIONS; FREQUENCY RESPONSE; HARMONICS; STRETCHING; FINITE DIFFERENCE THEORY
Download or read book Surface Modeling Grid Generation and Related Issues in Computational Fluid Dynamic CFD Solutions written by and published by . This book was released on 1995 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atmospheric Modeling Data Assimilation and Predictability written by Eugenia Kalnay and published by Cambridge University Press. This book was released on 2003 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, first published in 2002, is a graduate-level text on numerical weather prediction, including atmospheric modeling, data assimilation and predictability.
Download or read book Making Its Mark Proceedings Of The 7th Ecmwf Workshop On The Use Of Parallel Processors In Meteorology written by Geerd-r Hoffmann and published by World Scientific. This book was released on 1998-02-11 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for greater computer power in numerical weather prediction and meteorological research is as strong as ever. The world meteorological community has tried to meet this demand by exploiting parallelism. In this field, the European Centre for Medium-Range Weather Forecasts has established itself as the central venue for bringing together operational weather forecasters, climate researchers and parallel computer manufacturers to share their experiences through a series of workshops held every other year. This book reports on the latest workshop (2-6 December 1996) and is an excellent overview of the success which parallel systems have gained in meteorology worldwide, and how it was achieved. In addition, future trends in computer hardware and software development and its implications for meteorological computing are outlined.
Download or read book Numerical Modeling of the Global Atmosphere in the Climate System written by Philip Mote and published by Springer Science & Business Media. This book was released on 2000-04-30 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: 21. Simulating Future Climate G. J. Boer 1 Introduction. . . . . . . . . . . . . . . . 489 2 International Aspects . . . . . . . . . . . 490 3 Simulating Historical and Future Climate 492 4 Climate Change in the 20th Century . . . 495 5 Simulating Future Climate Change 498 6 Climate Impact, Adaptation, and Mitigation 501 7 Summary . 502 Index 505 PREFACE Numerical modeling ofthe global atmosphere has entered a new era. Whereas atmospheric modeling was once the domain ofa few research units at universities or government laboratories, it can now be performed almost anywhere thanks to the affordability of computing power. Atmospheric general circulation models (GCMs) are being used by a rapidly growing scientific community in a wide range of applications. With widespread interest in anthropogenic climate change, GCMs have a role also in informing policy discussions. Many of the scientists using GCMs have backgrounds in fields other than atmospheric sciences and may be unaware of how GCMs are constructed. Recognizing this explosion in the application of GCMs, we organized a two week course in order to give young scientists who are relatively new to the field of atmospheric modeling a thorough grounding in the basic principles on which GCMs are constructed, an insight into their strengths and weaknesses, and guid ance on how meaningful numerical experiments are formulated and analyzed. Sponsored by the North Atlantic Treaty Organization (NATO) and other institu tions, this Advanced Study Institute (ASI) took place May 25-June 5, 1998, at II Ciocco, a remote hotel on a Tuscan hillside in Italy.
Download or read book General Momentum Theory for Horizontal Axis Wind Turbines written by Jens Nørkær Sørensen and published by Springer. This book was released on 2015-08-17 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reconsiders the basic approaches behind the BEM method and in particular assesses and validates the equations forming the general momentum theory. One part of the book concerns the validation, using numerical fluid mechanics (CFD), of the different terms in the equations forming the momentum theory. Other parts present new ideas for extending the theory and for enhancing the accuracy of the BEM approach. Besides a general introduction and explanation of the momentum theory, the book also deals with specialized topics, such as diffusor-augmented rotors, wind tunnel corrections, tip corrections, and combined momentum/vortex theory for design of wind turbine rotors. The book contains new as well as already published material, and the author has strived to put the material into a new and more consistent context than what usually is found in similar text books. The book is primarily intended for researchers and experienced students with a basic knowledge in fluid mechanics wishing to understand and expand their knowledge on wind turbine aerodynamics. The book is self-consistent, hence all necessary derivations are shown, and it should not be necessary to seek help in other literature to understand the contents of the book.
Download or read book Prediction of Turbulent Flows written by Geoff Hewitt and published by Cambridge University Press. This book was released on 2005-06-08 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prediction of turbulent flows is of paramount importance in the development of complex engineering systems involving flow, heat and mass transfer, and chemical reactions. Arising from a programme held at the Isaac Newton Institute in Cambridge, this volume reviews the current situation regarding the prediction of such flows through the use of modern computational fluid dynamics techniques, and attempts to address the inherent problem of modelling turbulence. In particular, the current physical understanding of such flows is summarised and the resulting implications for simulation discussed. The volume continues by surveying current approximation methods whilst discussing their applicability to industrial problems. This major work concludes by providing a specific set of guidelines for selecting the most appropriate model for a given problem. Unique in its breadth and critical approach, this book will be of immense value to experienced practitioners and researchers, continuing the UK's strong tradition in fluid dynamics.
Download or read book Direct and Large Eddy Simulation written by Bernard J. Geurts and published by Walter de Gruyter GmbH & Co KG. This book was released on 2022-12-05 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive overview of the mathematics and physics behind the simulation of turbulent flows and discusses in detail (i) the phenomenology of turbulence in fluid dynamics, (ii) the role of direct and large-eddy simulation in predicting these dynamics, (iii) the multiple considerations underpinning subgrid modelling, and, (iv) the issue of validation and reliability resulting from interacting modelling and numerical errors.
Download or read book The Seismic Velocity Model as an Interpretation Asset written by Phil Schultz and published by SEG Books. This book was released on 1998-12-30 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: A 3D velocity model is built with a both geophysical and geologic input because of the accuracy demands of depth imaging, so it becomes an increasingly effective interpretive tool. This book addresses ways in which the interpreter should participate in development of the model and underscores its interpretive value with case study examples.
Download or read book Proceedings of the Annual Climate Diagnostics Workshop written by and published by . This book was released on 2000 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conference on Numerical Weather Prediction written by and published by . This book was released on 1999 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Direct and Large Eddy Simulation IV written by Bernard Geurts and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 543 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the 2001 DLES4 workshop. It describes and discusses state-of-the-art modeling and simulation approaches for complex flows. Fundamental turbulence and modeling issues but also elements from modern numerical analysis are at the heart of this field of interest.
Download or read book Advances in DNS LES written by Chaoqun Liu and published by . This book was released on 1997 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
