Numerical Simulation of Natural Convection in Heterogeneous Porous media for CO2 Geological Storage

Numerical Simulation of Natural Convection in Heterogeneous Porous media for CO2 Geological Storage

Ranganathan, P.
Farajzadeh, R.
Bruining, J.
Zitha, P.L.J.

Civil Engineering and Geosciences

Geoscience & Engineering

2012-08-10

We report a modeling and numerical simulation study of density-driven natural convection during geological CO2 storage in heterogeneous formations. We consider an aquifer or depleted oilfield overlain by gaseous CO2, where the water density increases due to CO2 dissolution. The heterogeneity of the aquifer is represented by spatial variations of the permeability, generated using Sequential Gaussian Simulation method. The convective motion of the liquid with dissolved CO2 is investigated. Special attention is paid to instability characteristics of theCO2 concentration profiles, variation ofmixing length, and averageCO2 mass flux as a function of the heterogeneity characterized by the standard deviation and the correlation length of the log-normal permeability fields. The CO2 concentration profiles show different flow patterns of convective mixing such as gravity fingering, channeling, and dispersive based on the heterogeneity medium of the aquifer. The variation of mixing length with dimensionless time shows three separate regimes such as diffusion, convection, and second diffusion. The average CO2 mass flux at the top boundary decreases quickly at early times then it increases, reaching a constant value at later times for various heterogeneity parameters.

density-driven natural convection
porous media
heterogeneity
CO2
solubility
mass transfer

http://resolver.tudelft.nl/uuid:1d912fc8-32be-4d2f-85db-af19547012ab

https://doi.org/10.1007/s11242-012-0031-z

Springer

0169-3913

Transport in Porous Media, 95 (1), 2012

Institutional Repository

journal article

© 2012 The Author(s)
This article is published with open access at Springerlink.com