4 research outputs found
Mesoscale fluid simulation with the Lattice Boltzmann method
PhDThis thesis describes investigations of several complex fluid effects., including
hydrodynamic spinodal decomposition, viscous instability. and self-assembly of a
cubic surfactant phase, by simulating them with a lattice Boltzmann computational
model.
The introduction describes what is meant by the term "complex fluid", and why
such fluids are both important and difficult to understand. A key feature of complex
fluids is that their behaviour spans length and time scales. The lattice Boltzmann
method is presented as a modelling technique which sits at a "mesoscale" level
intermediate between coarse-grained and fine-grained detail, and which is therefore
ideal for modelling certain classes of complex fluids.
The following chapters describe simulations which have been performed using
this technique, in two and three dimensions. Chapter 2 presents an investigation
into the separation of a mixture of two fluids. This process is found to involve several
physical mechanisms at different stages. The simulated behaviour is found to be in
good agreement with existing theory, and a curious effect, due to multiple competing
mechanisms, is observed, in agreement with experiments and other simulations.
Chapter 3 describes an improvement to lattice Boltzmann models of Hele-Shaw
flow, along with simulations which quantitatively demonstrate improvements in both
accuracy and numerical stability. The Saffman-Taylor hydrodynamic instability is
demonstrated using this model.
Chapter 4 contains the details and results of the TeraGyroid experiment, which
involved extremely large-scale simulations to investigate the dynamical behaviour
of a self-assembling structure. The first finite- size-effect- free dynamical simulations
of such a system are presented. It is found that several different mechanisms are
responsible for the assembly; the existence of chiral domains is demonstrated, along
with an examination of domain growth during self-assembly.
Appendix A describes some aspects of the implementation of the lattice Boltzmann
codes used in this thesis; appendix B describes some of the Grid computing
techniques which were necessary for the simulations of chapter 4.
Chapter 5 summarises the work, and makes suggestions for further research and
improvement.Huntsman Corporation Queen Mary University Schlumberger Cambridge Researc
MS FT-2-2 7 Orthogonal polynomials and quadrature: Theory, computation, and applications
Quadrature rules find many applications in science and engineering. Their analysis is a classical area of applied mathematics and continues to attract considerable attention. This seminar brings together speakers with expertise in a large variety of quadrature rules. It is the aim of the seminar to provide an overview of recent developments in the analysis of quadrature rules. The computation of error estimates and novel applications also are described
Generalized averaged Gaussian quadrature and applications
A simple numerical method for constructing the optimal generalized averaged Gaussian quadrature formulas will be presented. These formulas exist in many cases in which real positive GaussKronrod formulas do not exist, and can be used as an adequate alternative in order to estimate the error of a Gaussian rule. We also investigate the conditions under which the optimal averaged Gaussian quadrature formulas and their truncated variants are internal
Pluris 2005: 1º Congresso Luso-Brasileiro para o Planejamento Urbano, Regional, Integrado e Sustentável.
[Excerto] Mais do que simplesmente o idioma, Brasil e Portugal partilham uma série de elementos comuns, muitos dos quais têm influência direta nas características das cidades e nos problemas que a estas acometem, apesar das evidentes diferenças de escala.
Isto só reforça a necessidade de um esforço conjunto de pesquisadores
dos dois países para trabalhar nas temáticas relacionadas com o
planejamento urbano e regional, de forma integrada e visando um
processo de desenvolvimento sustentável.
Esta foi a motivação para a realização deste congresso, que pretende
aproximar os grupos de pesquisas dos dois países de forma a produzir
novas parcerias e projetos conjuntos a partir do interesse comum em
resolver problemas semelhantes ou não, razão pela qual abre-se um
razoável leque de tópicos para submissão de trabalhos.
O interesse não se restringe, no entanto, aos casos de Brasil e Portugal.
Assim sendo, trabalhos de outros países, tanto desenvolvidos como em
desenvolvimento, também estão presentes no evento. [...