MOTIVATIONS
Matter, conceptually classified
into fluids and solids, can be fully
described by the microscopic physics of its constituent molecules
or
particles. However, for most engineering applications, a macroscopic
or
continuum description has usually been sufficient. The
macroscopic / continuum approach is successful because there
is a great
disparity between the macroscopic spatial and temporal scales
relevant
to these applications and the corresponding microscopic scales.
Microscopic dynamics merely determines material properties
like the
transport coefficients of a fluid or the elastic moduli of
a solid,
which cannot be derived within the macroscopic framework. The
macroscopic dynamics is therefore insensitive to the details
of the
underlying microscopic dynamics; indeed, if the material properties
are
simply measured experimentally, then the microscopic dynamics
is largely
irrelevant.
This traditional picture of the role of microscopic and macroscopic
physics is now being challenged as new multi-scale and multi-physics
problems have begun to emerge in many fields. For example,
in
nano-scale systems, the scale separation assumption does not
hold;
macroscopic theory is therefore inadequate, yet microscopic
theory may
be impractical because it requires computational capabilities
far beyond
our present reach. This new class of problems poses unprecedented
challenges to mathematical modelling and numerical simulation
and
requires new and non--traditional analysis and modelling paradigms.
Methods based on mesoscopic theories, which connect the microscopic
and
macroscopic descriptions of the dynamics, provide a promising
approach.
They can lead to useful models, possibly requiring empirical
inputs to
determine some of the model parameters, which are adequate
to simulate
the relevant physical phenomena. An important challenge will
be to
construct such mesoscopic models by identifying the optimal
minimal
relevant information from the microscopic dynamics.
The mission of this International Conference Series
on Mesoscopic Methods in Engineering and Science is
to bring together researchers
and
practitioners in various engineering and scientific fields
to focus on
the emerging methods based on mesoscopic theory. Notable examples
include the Lattice Gas Cellular Automata (LGCA), the Lattice
Boltzmann
Equation (LBE), the Discrete Velocity Models (DVM), the
Gas-Kinetic Scheme (GKS), and the Smoothed Particle Hydrodynamics
(SPH). Although these methods are sometimes designed for
macroscopic hydrodynamics, they are not based upon macroscopic
equations
like the
Navier-Stokes equations; instead, they are closely related
to kinetic
theory and the Boltzmann equation. These methods are promising
candidates to effectively connect microscopic and macroscopic
physics
and thereby substantially extend our analytical and computational
capabilities.
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