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CHAPTER 1
INTRODUCTION
If we knew what it was we were doing, it would not
be called research, would it? textssssssssssssssssssss
Albert Einstein
Fluid flow and mass transport in porous media is an important process
in natural composite materials (soils, rocks, woods, hard and soft tissues,
etc.) and many engineered composites (concrete, bioengineered tissues, etc.),
at various spatial and temporal scales. Each of these scales contains specific information
about the underlying physical process. Pore-scale modeling together
with upscaling techniques allow the transfer of information, i.e., laws which
are given on a micro-scale to laws valid on a larger scales. To do so, it is necessary
to identify and understand (multiphase) flow and (reactive) transport
processes at microscopic scale and to describe their manifestation at the macroscopic
level (core or field scale). In the case of virus and colloid transport in
porous media, understanding the transport mechanisms has recently attracted
significant attention, especially in the case of groundwater polluted by contaminants
that could adsorb to colloids. Colloids can enhance pollutant mobility
[McCarthy and Zachara, 1989], and field-based results suggest the importance
of colloids in the transport of low-solubility contaminants [Vilks et al., 1997,
Kersting et al., 1999]. Enhanced mobility together with very limited acceptable
concentrations of hazardous solutes (in the range of few parts per billion) have
raised more attention to the modeling and accurate prediction of the migration
and distribution of contaminants.
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