An Integrated Approach To The Parallel Processing Of Explicit Discrete Element Problems

This book is the ?nal outcome of VECPAR 2000 – 4th International Meeting on Vector and Parallel Processing. VECPAR constitutes a series of conferences, which have been organized by the Faculty of Engineering of the University of Porto since 1993, with the main objective of disseminating new knowledge on parallel computing. Readership of This Book The book is aimed at an audience of researchers and graduate students in a broad range of scienti?c areas, including not only computer science, but also applied mathematics and numerical analysis, physics, and engineering. Book Plan From a total of 66 papers selected on the basis of extended abstracts for p- sentation at the conference, a subset of 34 papers were chosen during a second review process leading to their inclusion in the book, together with the invited talks. The book contains a total of 40 papers organized into 6 chapters, where each may appeal to people in di?erent but still related scienti?c areas. All ch- ters, with the exception of Chapter 6, are initiated by a short text, providing a quick overview of the organization and papers in the chapter. The 13 papers in Chapter 1 cover the aspects related to the use of multiple processors. Operating systems, languages and software tools for scheduling, and code transformation are the topics included in this chapter, initiated by the talk on computing over the Internet, entitled Grid Computing,byIan Foster.

An informative look at the theory, computer implementation, and application of the scaled boundary finite element method This reliable resource, complete with MATLAB, is an easy-to-understand introduction to the fundamental principles of the scaled boundary finite element method. It establishes the theory of the scaled boundary finite element method systematically as a general numerical procedure, providing the reader with a sound knowledge to expand the applications of this method to a broader scope. The book also presents the applications of the scaled boundary finite element to illustrate its salient features and potentials. The Scaled Boundary Finite Element Method: Introduction to Theory and Implementation covers the static and dynamic stress analysis of solids in two and three dimensions. The relevant concepts, theory and modelling issues of the scaled boundary finite element method are discussed and the unique features of the method are highlighted. The applications in computational fracture mechanics are detailed with numerical examples. A unified mesh generation procedure based on quadtree/octree algorithm is described. It also presents examples of fully automatic stress analysis of geometric models in NURBS, STL and digital images. Written in lucid and easy to understand language by the co-inventor of the scaled boundary element method Provides MATLAB as an integral part of the book with the code cross-referenced in the text and the use of the code illustrated by examples Presents new developments in the scaled boundary finite element method with illustrative examples so that readers can appreciate the significant features and potentials of this novel method—especially in emerging technologies such as 3D printing, virtual reality, and digital image-based analysis The Scaled Boundary Finite Element Method: Introduction to Theory and Implementation is an ideal book for researchers, software developers, numerical analysts, and postgraduate students in many fields of engineering and science.

The aim of this major reference work is to provide a first point of entry to the literature for the researchers in any field relating to structural integrity in the form of a definitive research/reference tool which links the various sub-disciplines that comprise the whole of structural integrity. Special emphasis will be given to the interaction between mechanics and materials and structural integrity applications. Because of the interdisciplinary and applied nature of the work, it will be of interest to mechanical engineers and materials scientists from both academic and industrial backgrounds including bioengineering, interface engineering and nanotechnology. The scope of this work encompasses, but is not restricted to: fracture mechanics, fatigue, creep, materials, dynamics, environmental degradation, numerical methods, failure mechanisms and damage mechanics, interfacial fracture and nano-technology, structural analysis, surface behaviour and heart valves. The structures under consideration include: pressure vessels and piping, off-shore structures, gas installations and pipelines, chemical plants, aircraft, railways, bridges, plates and shells, electronic circuits, interfaces, nanotechnology, artificial organs, biomaterial prostheses, cast structures, mining... and more. Case studies will form an integral part of the work.

Granular materials are highly present in various industrial practices and as such their proper handling is of utmost economic importance. With the advancement of computers processing capacity, numerical simulation techniques are increasingly used to compute the dynamics of granular systems. Discrete Element Method (DEM) is widely used to predict the motion of the granular assembly by analyzing the forces on each individual grain/particle at each tiny time step. Such a detailed analysis, however, comes at the cost of huge computational time and power even with today's highly efficient supercomputers. The current book discusses alternative numerical integration algorithms with the focus on the comparison between implicit and explicit methods. Several test cases are presented. The analysis of forward and reverse acting grates is, in particular, elaborated and includes residence time distribution analysis and validation of the simulation results with experiments. The book is especially useful to academics who seek a deeper understanding than simple utilization of commercial DEM codes but also to any individual who is interested in research and development of current DEM algorithms.

The Cell Method (CM) is a computational tool that maintains critical multidimensional attributes of physical phenomena in analysis. This information is neglected in the differential formulations of the classical approaches of finite element, boundary element, finite volume, and finite difference analysis, often leading to numerical instabilities and spurious results. This book highlights the central theoretical concepts of the CM that preserve a more accurate and precise representation of the geometric and topological features of variables for practical problem solving. Important applications occur in fields such as electromagnetics, electrodynamics, solid mechanics and fluids. CM addresses non-locality in continuum mechanics, an especially important circumstance in modeling heterogeneous materials. Professional engineers and scientists, as well as graduate students, are offered: • A general overview of physics and its mathematical descriptions; • Guidance on how to build direct, discrete formulations; • Coverage of the governing equations of the CM, including nonlocality; • Explanations of the use of Tonti diagrams; and • References for further reading.

Presently, there is a strong need for better understanding of the limits of the multi-scale and multi-physics methodology in terms of its practical value for modeling the behavior of a given engineering structure, regarding the solution cost, result interpretation and model reliability. The issues concerning the formulation of a multi-physics problem, capturing the different scales in the solution and providing error estimates and bounds on the computed solution should all be examined. Another key issue in that sense concerns our ability to bring these advances in multi-scale and multi-physics nonlinear analysis to bear upon the solution of practically unlimited new capabilities of achieving the optimal design of structures under extreme conditions. In other words, the necessity for introducing a refined modeling approach is not only created by available computational tools, but more importantly to provide a better insight into any potential weakness of a structural system on hand and thus achieve a more economical design. requirements of the market economies, where in a number of very competitive industrial sectors the need for economic design leads naturally towards the criteria based on ultimate limit state of a particular structural system on hand. This book allows exchange of the ideas on advanced computational models and techniques applicable to interdisciplinary, coupled and interaction problems, which are governing the complex behavior of engineering structures.