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Multi-scale gas transport modelling for the EC FORGE project

Published online by Cambridge University Press:  02 January 2018

A. E. Bond ,
K. E. Thatcher  and
S. Norris
A. E. Bond*
Affiliation:
Quintessa Limited, 633/635 Birchwood Boulevard, Birchwood, Warrington, Cheshire, WA3 7QU, UK
K. E. Thatcher
Affiliation:
Quintessa Limited, 633/635 Birchwood Boulevard, Birchwood, Warrington, Cheshire, WA3 7QU, UK
S. Norris
Affiliation:
Radioactive Waste Management Limited, Building 587, Curie Avenue, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0RH, UK
*
*E-mail: alexbond@quintessa.org
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Abstract

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The generation and migration of gas within and around proposed radioactive waste disposal facilities is potentially a safety critical process. A safety case for a facility that generates significant quantities of gas (e.g. through metal corrosion or radiolysis) will require demonstration that gas migration around and away from the waste is sufficiently understood and will not breach the safety case for the facility. Models can be used to understand the likely hydraulic evolution of such a disposal facility, but the models need to consider processes over a range of scales. A whole repository may extend over kilometres, with individual disposal cells at the scale of tens of metres and features which provide pathways for gas migration on a centimetre scale. All of these features may be significant from a safety perspective and capturing the impact of all of these features in a single model is a significant challenge.

This paper presents an approach to tackling this multi-scale problem, which allows the whole repository to be modelled in a computationally efficient manner. The approach involves identifying areas within the modelled domain that show very similar behaviour, and representing these areas with sub-models, so that small-scale features are retained, but computational overhead is decreased by using the results in more than one location in the model domain. The approach allowed a model of a whole repository to be run on a single processor core, whilst maintaining the small-scale features of the system. The model results were compared against more conventional upscaling techniques and show the advantage of a more detailed representation of small-scale features. The model results reflect the conceptual understanding of how gas would migrate in a repository.

Keywords

radioactive wastegasnumerical modellingmulti-scale
Type
Research Article
Information
Mineralogical Magazine , Volume 79 , Issue 6 , November 2015 , pp. 1251 - 1263
Creative Commons
Creative Common License - CCCreative Common License - BY
Copyright © The Mineralogical Society of Great Britain and Ireland 2015. This is an open access article, distributed under the terms of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2015

References

Benbow, S.J., Rivett, M.O., Chittenden, N., Herbert, A. W, Watson, S., Williams, S.J. and Norris, S. (2014) Potential migration of buoyant LNAPL from Intermediate Level Waste (ILW) emplaced in a geological disposal facility (GDF) for UK radioactive waste. Journal ofContaminant Hydrology, 167, 1–22. http://dx.doi.org/10.1016/j.jconhyd.2014.07.011 CrossRefGoogle Scholar
Bond, A. and Watson, S. (2012) Understanding the post-closure thermal impact of HA/SF waste packages. Quintessa Report for NDA RWMD QRS-1384Q-R2 v2.1. http://www.nda.gov.uk/publication/qrs-1384q-r2-v2-1/ Google Scholar
Bond, A.E., Metcalfe, R., Maul, P.R., Suckling, P., Thatcher, K., Walke, R., Smith, K., Rasse, D., Steven, M. and Jones, D. (2013a) Systems analysis of field and laboratory experiments considering impacts of CO2 leakage in terrestrial systems. Energy Procedia, 37, 3394–3402. http://dx.doi.org/10.1016/j.egypro.2013.06.228 CrossRefGoogle Scholar
Bond, A., Millard, A., Nakama, S., Zhang, C. and Garitte, B. (2013b) Approaches for representing hydromech-anical coupling between large engineered voids and argillaceous porous media at ventilation experiment, Mont Terri. Journal of Rock Mechanics and Geotechnical Engineering, 5(2). http://dx.doi.org/10.1016/j.jrmge.2013.02.002 CrossRefGoogle Scholar
Bond, A., Benbow, S., Wilson, J., Millard, A., Nakama, S. and English, M. (2013c) Reactive and nonreactive transport modelling in partially water saturated argillaceous porous media around the ventilation experiment, Mont-Terri. Journal of Rock Mechanics and Geotechnical Engineering, 5(1). http://dx.doi.org/10.1016/j.jrmge.2012.06.001 CrossRefGoogle Scholar
Byrne, G.D. and Hindmarsh, A.C. (1975) A polyalgo-rithm for the numerical solution of differential-algebraic equations. ACM Transactions on Mathematical Software, 1, 71–96.CrossRefGoogle Scholar
Chen, Z., Huan, G. and Ma, Y (2006) Computational Methods for Multiphase Flows in Porous Media. SIAM, Society for Industrial and Applied Mathematics, Philadelphia. http://dx.doi.org/10.1137/1.9780898718942 CrossRefGoogle Scholar
De La Vaissiere, R., Morel, J., Noiret, A., Côte, P., Helmlinger, B., Sohrabi, R., Lavanchy, J-M., Leveau, E, Nussbaum, C. and Morel, J. (2014) Excavation-induced fractures network surrounding tunnel: properties and evolution under loading. Geological Society, London, Special Publications, 400, 279–291. http://dx.doi.org/10.1144/SP400.30 CrossRefGoogle Scholar
Engel, J., Schanz, T. and Lauer, C. (2003) State parameters for unsaturated soils, basic empirical concepts. pp. 125–138 in: Proceedings of International Conference, From Experimental Evidence towards Numerical Modeling of Unsaturated Soils, Weimar, Germany, 2003 (T. Schanz, editor), 2, Springer, Berlin.Google Scholar
McDermott, C.I., Lodemann, M., Ghergut, I., Tenzer, H., Sauter, M. and Kolditz, O. (2006) Investigation of coupled hydraulic-geomechanical processes at the KTB site: pressure-dependent characteristics of a long-term pump test and elastic interpretation using a geomechanical facies model. Geofluids, 6, 67–81. http://dx.doi.org/10.1111/j.1468-8123.2006.00129.x CrossRefGoogle Scholar
McDermott, C., Walsh, R., Mettier, R., Kosakowski, G. and Kolditz, O. (2009) Hybrid analytical and finite element numerical modeling of mass and heat transport in fractured rocks with matrix diffusion. Computational Geosciences, 13, 349–361. http://dx.doi.org/10.1007/s10596-008-9123-9 CrossRefGoogle Scholar
Poller, A, Enssle, C.P., Mayer, G., Croise, 1 and Wendling, J. (2011) Repository-scale modelling of the long-term hydraulic perturbation induced by gas and heat generation in a geological repository for high and intermediate level radioactive waste: Methodology and example of applications. Transport in Porous Media, 90, 77–94.CrossRefGoogle Scholar
Towler, G. and Bond, A.E. (2011) Investigation of Gas Generation and Resaturation Issues: Input to EC FORGE Project. QRS-1378ZC-R2 v1.0. http://www.nda.gov.uk/publication/investigation-of-gas-generation-and-resaturation-issues-input-to-ec-forge-project-july-2011/ Google Scholar
Quintessa (2012) QPAC: Quintessa's general-purpose modelling software. Quintessa Report QRS-QPAC-11 March 2012 (http://www.quintessa.org/qpac-overview-report.pdf).Google Scholar
Versteeg, H. and Malalasekra, W. (2007) An Introduction to Computational Fluid Dynamics: The Finite Volume Method (2nd edition). Pearson Education Limited.Google Scholar
Wendling, J. (Compiler). (2013a) Final report on benchmark studies on repository-scale numerical simulations of gas migration Part 1: cell scale benchmark. FORGE Reports, D1.4R and D1.6-R pt 3. 102 pp. http://www.bgs.ac.uk/forge/docs/reports/D1.6-R.pdf Google Scholar
Wendling, J. (Compiler). (2013b) Final report on benchmark studies on repository-scale numerical simulations of gas migration Part 2: module scale benchmark. FORGE Reports, D1.4R and D1.6-R pt 3. 102 pp. http ://www.bgs.ac.uk/forge/docs/reports/D 1.6-R.pdfGoogle Scholar
Wendling, J. (Compiler). (2013c) Final report on benchmark studies on repository-scale numerical simulations of gas migration Part 3: repository scale benchmark. FORGE Reports, D1.4R and D1.6-R pt 3. 102 pp. http://www.bgs.ac.uk/forge/docs/reports/D1.6-R.pdf Google Scholar
Zienkiewicz, O.C., Taylor, R.L. andZhu, J.Z. (2005) The Finite Element Method: Its Basis and Fundamentals. Butterworth-Heinemann. ISBN: 978-1-85617-633-0.Google Scholar