Hybrid Numerical Methods for Multiscale Simulations of Subsurface Biogeochemical Processes Page: 4 of 6
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
SciDAC 2007 IOP Publishing
Journal of Physics: Conference Series 78 (2007) 012063 doi:10.1088/1742-6596/78/1/012063
This coupling/feedback leads to strong non-linearity in apparent continuum-scale behavior, and this
behavior is not well represented by averaged properties and state variables.
The experiment shown in Figure 1 provides a relevant example of such a system. In this
experiment, two solutes mix and react to precipitate calcium carbonate minerals (e.g., calcite) within a
very narrow zone in the center of the experimental cell. We have performed pore-scale simulations of
the mixing and reaction processes in this type of system [8] as shown in Figure 2. The simulation
results indicate that 1) strong mixing of the two solutes is limited to a very local region (only a few
grains wide), and 2) the mixing is inhibited by mineral precipitation leading to a strong negative
feedback or coupling between the reaction and transport across the narrow mixing zone in which
precipitation occurs. In this case, the precipitation/dissolution reaction described in detail by the pore
scale model is not easily represented at the continuum scale, but it could be efficiently modeled by
simulating the narrow mixing zone with the SPH model at the pore scale and simulating the remainder
of the model domain with a computationally efficient continuum-scale model.
* F - -w n - --
e~ . .
-- ae
Na2CO3 CaCh
Figure 1. Mesoscale experimental flow Figure 2. Pore-scale simulation of mixing of two
cell (60 cm by 60 cm). The flow cell is solutes (blue and red) and reaction to form
filled with 0.5 mm quartz sand and is precipitated solid mineral (green). Details of the
relatively thin in the third dimension. Two simulation method are provided in [8].
solutes are injected along two halves of the
lower boundary as indicated by the red and
blue arrows. The reaction causes
precipitation of calcium carbonate
minerals (the white zone approximately
0.5 cm wide in the center of the flow cell).
2. Hybrid Multiscale Modeling Methods
Published reviews of hybrid multiscale modeling concepts are provided by [5, 7]. Hybrid multiscale
modeling methods have been most widely applied in the fields of materials science and chemical
engineering, in which atomic-scale models of molecular dynamics (MD) have been linked to
continuum-scale models of material deposition, strength, deformation, and failure. A recent review of
3
Upcoming Pages
Here’s what’s next.
Search Inside
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Scheibe, Timothy D.; Tartakovsky, Alexandre M.; Tartakovsky, Daniel M.; Redden, George D. & Meakin, Paul. Hybrid Numerical Methods for Multiscale Simulations of Subsurface Biogeochemical Processes, article, August 1, 2007; (https://digital.library.unt.edu/ark:/67531/metadc878193/m1/4/: accessed March 19, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.