Hostname: page-component-54dcc4c588-nx7b4 Total loading time: 0 Render date: 2025-10-10T10:55:20.018Z Has data issue: false hasContentIssue false
  • English
  • Français

Investigation of the Influence of Heterogeneous Porosity onMatrix Diffusion: a Novel Approach Using Adaptive Tree-Multigrid Techniqueand Real Porosity Data

Published online by Cambridge University Press:  03 September 2012

P. Simbierowicz  and
M. Olin
P. Simbierowicz
Affiliation:
VTT Chemical Technology, P.O. Box 1404 (Otakaari 3A, ESPOO), FIN-02044 VTT, Finland
M. Olin
Affiliation:
VTT Chemical Technology, P.O. Box 1404 (Otakaari 3A, ESPOO), FIN-02044 VTT, Finland
Get access

Abstract

Last year we developed a two-dimensional deterministic heterogeneous matrixdiffusion model, which is capable of utilising porosity informationoriginating from real drill-core samples. The results of numericalinfiltration experiment we had performed with the model displayedsubstantial spatial variations in the penetration depth. Because it ispractically impossible to verify experimentally those two-dimensionalpenetration profiles we had computed, this time we decided to try modellingof measured leaching curves. Unfortunately we have not succeeded inacquiring such curves for the exact same samples, which we have used innumerical leaching experiments. Nevertheless it can be seen, that the shapeof leaching curves computed with the heterogeneous model is clearly closerto the shape of measured curves, than the shape of curves provided by thestandard model. These differences can be utilised as a basis for anapproximate numerical method of assessing the geometric factor, which hastraditionally been a purely empirical parameter.

The results of the new numerical experiments agree with our older resultsfrom last year: the heterogeneity of the rock matrix has highly significantimpact on the diffusion. However, when interpreting the results, one mustnot neglect numerous limitations of the model, and hence, one should notattempt to overgeneralise the conclusions.

Information

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 465: Symposium II – Scienfific Basis for Nuclear Waste Management XX , 1996 , 847
Copyright
Copyright © Materials Research Society 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

REFERENCES

1. Neretnieks, I., J. Geosphys. Res. 85 (B8), 4379–4397, (1980).Google Scholar
2. Olin, M., PhD thesis, VTT Publications 175, (1994).Google Scholar
3. Hemingway, S.J., Bradbury, M.H. & Lever, D.A., Report AERE-R 10691, (1983).Google Scholar
4. Lehikoinen, J., Muurinen, A., Olin, M., Uusheimo, K. & Valkiainen, M., VTT Research Notes 1394, (1992). 28 pp.Google Scholar
5. Hellmuth, K-H. & Siitari-Kauppi, M., Report STUK-B-VALO 63, (1990).Google Scholar
6. Gáspár, C., Józsa, J., Simbierowicz, P., in First International Conference on Water Pollution, edited by Wróbel, L.C. & Brebbia, C.A., (Elsevier, 1991). p. 299.Google Scholar
7. Gáspár, C. & Simbierowicz, P., in HYDROCOMP '92 Conference edited by Gayer, J., Starosolszky, O. & Maksimovic, C. (1992). p. 131.Google Scholar
8. Gáspár, C. & Simbierowicz, P., in IX. International Conference on Computational Methods in Water Resources, edited by Russell, T.F., Ewing, R.E., Brebbia, C. A., Gray, W.G. & Pinder, G.F. (Elsevier, 1992). p. 555.Google Scholar
9. Hackbusch, W., Multi-Grid Methods and Applications. (Springer-Verlag, Heidelberg 1985). 377 pp.Google Scholar
10. Simbierowicz, P. & Olin, M., Porosity and pore-structure as relevant parameters of matrix diffusion. VTT internal report (Espoo, 1995). 8 pp.Google Scholar