These proceedings contain the papers presented at the Fourth International Conference on Finite Elements in Water Resources, held in June, 1982, at the University of Hannover, Federal Re public of Germany. This Conference continued the successful series of previous conferences held at Princeton University in 1976, at Imperial College in 1978, and at the University of Mississippi in 1980. Since Finite Elements have proved to be a powerful means for analysing water resource problems, the principal objective of the Conference was to provide an exchange of experiences in practical applications of the finite element method and to establish a forum for discussion regarding accuracy, economy, limitations and improvements. Related discretization methods were included within the scope of the Conference. New develop ments in numerical and computational techniques, basic mathe matical formulations, and soft- and hardware aspects were considered to be equally important topics for an exchange of ideas between both theoretically and practically oriented re searchers. The Conference Organizing Committee is very grateful to the many distinguished scientists who attended the Conference, and for their contributions towards the proceedings. This collection of papers in being made available to a wider audience of en gineers and scientists by CML Publications in Southampton, U.K.

Sponsored by the International Society for Computational Methods in Engineering

This book contains the edited proceedings of the 2nd Internat- ional Conference on Computationa1 Methods and Experimental Meas- urements held on board the QE2 liner from 27th June to 2nd Ju1y 1984. The meeting was sponsored by the International Society for Computationa1 Methods in Engineering and the Department of Civi1 Engineering, Southampton University and organized by the Computationa1 Mechanics Institute of Southampton, England. The QE2 provided an ideal environment for the international meeting and one that was equa11y convenient for the USA and European re- searchers and offered a 10cation propitious to the interchange of ideas and c10se contact between participants. This book covers a wide range of different topics in Computat- iona1 Methods and Experimental Measurements with the main empha- sis on the re1ationships between experimental and ana1ytica1 5- utions. The first section deals with fluid dynamics problems and a 1arge number of app1ications. Section 2 considers geophysica1 fluid dynamics and describes some atmospheric models and their re1ated problems. Water resources are dealt with in Section 3 which describes some app1ications of porous media f10w and sur- face water mode11ing. Wave interaction problems are described in Section 4 and Section 5 considers some important heat transfer app1ications. Other sections - 6 & 7 - study problems re1ated to stress analysis and structura1 app1ications. Vibration pro- blems are becoming of fundamental importance in engineering and part of the Conference Proceedings - Section 8 - are dedicated to the study of experimental and computational models.

One of the most interesting developments in engineering analysis during the last few years has been the rapid growth of boundary element methods. The first and second international conferences on this topic held in 1978 and 1980 attracted approximately 30 papers each, most of them from a few well known groups around the world. The third meeting in 1981, produced instead approximately 40 papers, many of them from young investigators working in newly created research groups. They have been attracted to boundary elements by the many advantages of the technique and were able to assimilate rapidly, the new ideas unencumbered by previous con ceptions. That third conference held in 1981 constituted in many ways a turning point for boundary elements and it indicated for the first time a general awareness of the industry to the research being carried out in the new technique. Engineering firms started to appreciate the advantages of the method mainly from the computa tional aided engineering point of view. The advantages of simple data input and output was rapidly understood by those professional engineers who were forced up to them to use cumbersome finite element codes. Boundary element practitioners in close contacts with the industry started to perceive that the method was gather ing a critical momentum of its own. This is now more evident by the diversity and quality of the papers in this volume, which are the edited Proceedings of the 4th International Conference, held at the University of Southampton in September 1982."

This book is the edited proceedings of the Fifth International Conference on Finite Elements in Water Resources, held at the University of Vermont, USA in June 1984. This Conference cont inues the successful series started at Princeton University in 1976, followed by the Conference in Imperial College, London, UK in 1978, the third Conference at the University of Mississippi, USA in 1980 and the fourth at the University of Hannover, Germany in 1982. The objective of this Conference is to provide engineers and scientists interested in water resources with the state-of-t- art on finite element modelling. The Proceedings review the basic theory and applications of the technique in groundwater and seepage, transport phenomena, viscous flow, river, lake and ocean modelling. The fundamentals of the numerical techniques employed in finite elements are also discussed. Many applications illus trate the versatility and generality of the Finite Element Method for the simulation of a wide range of problems in water resources. More recent schemes, in particular, boundary elements, are also presented, together with a series of advanced numerical techniques. The Conference has become an internationally accepted forum for the presentation of new developments of finite elements in water resources techniques. Because of this, a large number of abstracts were submitted to the Organizing Committee and it is our only reg ret that it was impossible to accept all these contributions. The overwhelming response to our Call for Papers has ensured the high quality of these proceedings.

The application of BEM in all fields of engineering and science has progressed at an accelerate rate since the first book on the method appeared in the late seventies. In particular the advantages of BEM for potential problems are essential to solve a whole range of electrical engineering problems. Previous volumes in this series have focussed on the state of the art in other fields while this volume discusses only problems related to electrical engineering. The book reviews a series of important applications such as the design of semiconductor devices and their thermal analysis. The following two chapters concentrate on the study of galvanic corrosion and cathodic protection. Chapter 4 deals with the design of capacitance transducers. The next three chapters concentrate on the applications of the method to simulate electrochemical problems with special reference to Plating Process. The last chapter in the book discusses the case of inverse problems in electrical engineering and presents some applications including their use in tomography.

VI SOCRATES: I think that we ought to stress that we will write only about things that we have first hand experience in, in a coherent way that will be useful to engineers and other scientists and stressing the formulation without being too mathematical. We should write with integrity and honesty, giving reference to other authors where reference is due, but avoiding mentioning everybody just to be certain that our book is widely advertised. Above all, the book should be clear and useful. PLATO: I think we should include a good discussion of fundamental ideas, of how integral equations are formed, pointing out that they are like two dimensional shadows of three dimensional objects, ... SOCRATES: Stop there! Remember you are not 'the' Plato! PLATO: Sorry, I was carried away. ARISTOTLE: I think that the book should have many applications so that the reader can learn by looking at them how to use the method. SOCRATES: I agree. But we should be careful. It is easy to include many illustra tions and examples in a book in order to disguise its meagre contents. All examples should be relevant. ARISTOTLE: And we should also include a full computer program to give the reader if so he wishes, a working experience of the technique.

This book constitutes the edited proceedings of the Advanced Studies Institute on Boundary Element Techniques in Computer Aided Engineering held at The Institute of Computational Mechanics, Ashurst Lodge, Southampton, England, from September 19 to 30, 1984. The Institute was held under the auspices of the newly launched "Double Jump Programme" which aims to bring together academics and industrial scientists. Consequently the programme was more industr ially based than other NATO ASI meetings, achieving an excellent combination of theoretical and practical aspects of the newly developed Boundary Element Method. In recent years engineers have become increasingly interested in the application of boundary element techniques for'the solution of continuum mechanics problems. The importance of boundary elements is that it combines the advantages of boundary integral equations (i.e. reduction of dimensionality of the problems, possibility of modelling domains extending to infinity, numerical accura'cy) with the versatility of finite elements (i.e. modelling of arbitrary curved surfaces). Because of this the technique has been well received by the engineering and scientific communities. Another important advantage of boundary elements stems from its reduction of dimensionality, that is that the technique requires much less data input than classical finite elements. This makes the method very well suited for Computer Aided Design and in great part explains the interest of the engineering profession in the new technique."

The boundary element method (BEM) is now a well-established numerical technique which provides an efficient alternative to the prevailing finite difference and finite element methods for the solution of a wide range of engineering problems. The main advantage of the BEM is its unique ability to provide a complete problem solution in terms of boundary values only, with substantial savings in computer time and data preparation effort. An initial restriction of the BEM was that the fundamental solution to the original partial differential equation was required in order to obtain an equivalent boundary in tegral equation. Another was that non-homogeneous terms accounting for effects such as distributed loads were included in the formulation by means of domain integrals, thus making the technique lose the attraction of its "boundary-only" character. Many different approaches have been developed to overcome these problems. It is our opinion that the most successful so far is the dual reciprocity method (DRM), which is the subject matter of this book. The basic idea behind this approach is to employ a fundamental solution corresponding to a simpler equation and to treat the remaining terms, as well as other non-homogeneous terms in the original equation, through a procedure which involves a series expansion using global approximating functions and the application of reciprocity principles.

This book covers the major areas of active research and uses and although advanced it presents the basic theory of how to apply BEM in acoustics as well as specific formulations for more complicated problems.

Over a period of several years the field of probabilistic mechanics and com putational mechanics have progressed vigorously, but independently. With the advent of powerful computational hardware and the development of novel mechanical techniques, the field of stochastic mechanics has progressed in such a manner that the inherent uncertainty of quite complicated systems can be addressed. The first International Conference on Computational Stochastic Mechanics was convened in Corfu in September 1991 in an ef fort to provide a forum for the exchanging of ideas on the current status of computational methods as applied to stochastic mechanics and for identi fying needs for further research. The Conference covered both theoretical techniques and practical applications. The Conference also celebrated the 60th anniversary of the birthday of Dr. Masanobu Shinozuka, the Sollenberger Professor of Civil Engineering at Princeton University, whose work has contributed in such a great measure to the development of Computational Stochastic Mechanics. A brief sum mary of his career and achievements are given in the Dedication. This book comprises some of the papers presented at the meeting and cov ers sections on Theoretical Reliability Analysis; Damage Analysis; Applied Reliability Analysis; Theoretical Random Vibrations; Stochastic Finite Ele ment Concept; Fatigue and Fracture; Monte Carlo Simulations; Earthquake Engineering Applications; Materials; Applied Random Vibrations; Applied Stochastic Finite Element Analysis, and Flow Related Applications and Chaotic Dynamics. The Editors hope that the book will be a valuable contribution to the grow ing literature covering the field of Computational Stochastic Mechanics.

This book comprises an edited version of the Proceedings of the 2nd Interna tional Conference on Applications of Supercomputers in Engineering which took place at the Massachusetts Institute of Technology, Cambridge, USA during August 1991. The Conference was organized by the Wessex Insti tute of Technology, Southampton, UK with the support of the International Society for Boundary Elements. The first International Conference on Ap plications of Supercomputers in Engineering held in Southampton, UK in September 1989 was a very successful meeting and the resulting Conference Proceedings are now widely distributed throughout the world. The revolutionary aspects of the next generation of computers are now fully recognised by many engineers and scientists. Vector and parallel computers form the basis of the computing power needed to address the complex prob lems with which engineers are faced. The new machines not only increase the size of the problems which can be solved, but also require a different computational approach to obtain the most efficient results.

The series is aimed specifically at publishing peer reviewed reviews and contributions presented at workshops and conferences. Each volume is associated with a particular conference, symposium or workshop. These events cover various topics within pure and applied mathematics and provide up-to-date coverage of new developments, methods and applications.

The series is aimed specifically at publishing peer reviewed reviews and contributions presented at workshops and conferences. Each volume is associated with a particular conference, symposium or workshop. These events cover various topics within pure and applied mathematics and provide up-to-date coverage of new developments, methods and applications.

Software for engineering applications has become, during the last few years, a multi-billion pound industry as applications of computer programs are now an essential part of any engineering project. In spite of this, engineer ing software is not always reliable and many fail to produce good solutions. The extent of this problem, which is very costly to the engineering industry, and its consequences, are somewhat hidden because the software industry has not reached the necessary maturity. An engineer needs a long training before being able to design a body for instance. However, to do that, he may use a computer program which has undergone no validation whatsoever and is written by someone without any engineering knowledge. It is imperative to address this problem to ensure that computer codes are properly prepared to provide good solutions, and that they are robust and reliable. This 2nd International Conference on Reliability and Robustness of En gineering Software (RRES 91) was called to address this problem. The meeting was held in Milan, Italy, in April 1991 and was of importance to engineers working in industry who are actively involved with the develop ment of computer codes.

The increasing size and complexity of new structural forces in engineering have made it necessary for designers to be aware of their dynamic behaviour. Dynamics is a subject which has traditionally been poorly taught in most engineering courses. This book was conceived as a way of providing engineers with a deeper knowledge of dynamic analysis and of indicating to them how some of the new vibrations problems can be solved. The authors start from basic principles to end up with the latest random vibration applications. The book originated 1n a week course given annually by the authors at the Computational Mechanics Centre, Ashurst Lodge, Southampton, England. Special care was taken to ensure continuity in the text and notations. Southampton 1984 CONTENTS Page Foreword Chapter 1 Introduction to Vibration 1. Introductory Remarks 1 2. Single Degree of Freedom Systems: Equations of Motion and Types of Problem 2 3. Response 6 4. General Structures: Equations of Motion 11 5. Response 15 6. Dynamic Interaction Problems 20 Chapter 2 Free Vibration, Resonance and Damping l. Introduction 25 25 2. Spring-Mass System 3. Simple Pendulum 27 4. Beam with Central Load 28 5. Rolling of a Ship 28 6. Springs in Parallel 30 7. Springs in Series 30 8. Free Vibration 31 9. Energy of Vibrating System 33 10. Damped Free Vibration 34 11. Undamped Forced Response 38 12. Damped Forced Response 39 13. Undamped Transient Vibration 42 14. Damped Transient Vibration 43 15.

This book constitutes the edited proceedings of the Advanced Studies Institute on Boundary Element Techniques in Computer Aided Engineering held at The Institute of Computational Mechanics, Ashurst Lodge, Southampton, England, from September 19 to 30, 1984. The Institute was held under the auspices of the newly launched "Double Jump Programme" which aims to bring together academics and industrial scientists. Consequently the programme was more industr ially based than other NATO ASI meetings, achieving an excellent combination of theoretical and practical aspects of the newly developed Boundary Element Method. In recent years engineers have become increasingly interested in the application of boundary element techniques for'the solution of continuum mechanics problems. The importance of boundary elements is that it combines the advantages of boundary integral equations (i.e. reduction of dimensionality of the problems, possibility of modelling domains extending to infinity, numerical accura'cy) with the versatility of finite elements (i.e. modelling of arbitrary curved surfaces). Because of this the technique has been well received by the engineering and scientific communities. Another important advantage of boundary elements stems from its reduction of dimensionality, that is that the technique requires much less data input than classical finite elements. This makes the method very well suited for Computer Aided Design and in great part explains the interest of the engineering profession in the new technique."

As the Boundary Element Method develops into a tool of engineering analysis more effort is dedicated to studying new applications and solving different problems. This book contains chapters on the basic principles of the technique, time dependent problems, fluid mechanics, hydraulics, geomechanics and plate bending. The number of non-linear and time dependent problems which have become amenable to solution using boundary elements have induced many researchers to investigate in depth the basis of the method. Chapter 0 of this book presents an ap proach based on weighted residual and error approximations, which permits easy construction of the governing boundary integral equations. Chapter I reviews the theoretical aspects of integral equation formulations with emphasis in their mathematical aspects. The analysis of time dependent problems is presented in Chap. 2 which describes the time and space dependent integral formulation of heat conduction problems and then proposes a numerical procedure and time marching algorithm. Chapter 3 reviews the application of boundary elements for fracture mechanics analysis in the presence of thermal stresses. The chapter presents numerical results and the considerations on numerical accuracy are of interest to analysts as well as practising engineers.

The use of fossil fuels has generated an increasing amount of interest in renewable energy resources. Energy policies and management are of primary importance to achieve the development of sustainability and need to be consistent with recent advances in energy production and distribution. Challenges lie as much in the conversion from renewable energies such as wind and solar to useful forms like electricity, heat and fuel at an acceptable cost (including environmental damage) as in the integration of these resources into an existing infrastructure. This volume includes collaborative research between different disciplines, including materials, energy networks, new energy resources, storage solutions, waste to energy systems, smart grids and many other related subjects.

Transportation in urban areas, with its related environmental and social impacts, is of significant concern for government policymakers and for the urban citizens who need efficient transport systems. This book presents extensive reviews of these systems to devise and then safeguard their operational use, maintenance, safety and security. The continuing requirement for better and more efficient urban transport systems and the need for a healthier environment has added to the increasing international desire for new technologies and developments in this essential field. The variety of topics covered reflects the complex interaction of urban transport systems with their environment and the need to establish integrated strategies.

The selected papers contained in this book present the latest research in one of the most challenging, yet most universally applicable areas of technology. Multiphase flows are found in all areas of technology and the range of related problems of interest is vast, including many areas of science and engineering. Recently multiphase fluid dynamics have generated a great deal of attention, leading to many notable advances in experimental, analytical and numerical studies. It is perhaps, however, work on numerical solutions which is the most noticeable owing to the continuing improvements in computer software tools. Progress in numerical methods has permitted the solution of many practical problems, helping to improve our understanding of the physics involved. The presented papers illustrate the close interaction between numerical modellers and researchers working to gradually resolve the many outstanding issues in our understanding of multiphase flow.

Comprising specially selected papers this book presents trans-disciplinary research on issues related to the nature of water, and its use and exploitation by society. The valuable research contained in this book demonstrates the need to bridge the gap between physical, biological, environmental and health sciences. Water is essential for sustaining life on our planet, nevertheless its unequal distribution is a source of permanent conflict. It is predicted that population growth and irregular rainfall, due to climate change, may lead to more restricted access to water in certain regions of the world. This problem is made even more severe by human actions that can cause degradation to nature and the environment. The availability of clean and inexpensive water can no longer be taken for granted as the need for water continues to increase due a growing global population. Heavy water consumers such as agriculture and industry often contribute to its contamination. Water distribution networks in urban areas and soiled water collection systems, present serious problems as well as the need to maintain ageing infrastructures. Possible technologically solutions, such as desalination or pumping systems are energy demanding but, as costs rise, the techniques currently developed may need to be re-assessed.