Investigation of CO2 Geologic Sequestration and the Density-driven Convection Process


In this work, the authors present a simulation study of the convection triggered by gravitational instability due to dissolution. By putting a denser fluid on the top, convection occurred as the upper fluid dissolved into the lighter fluid below. Five kinds of heterogeneous porous media are created with different values of correlation length of permeability. Simulation is conducted with compact finite difference scheme of high accuracy order and spectral method. The results show that flow patterns have a significant difference between heterogeneous porous media and homogeneous one.

Keywords: CO2 geologic sequestration, density-driven convection, stream-functionvorticity system, pseudo-spectral method, compact finite difference

[1] Orr, F. M. (2009). Onshore geologic storage of CO2. Science, vol. 325, no. 5948, pp. 1656–1658.

[2] Huppert, H. E. and Neufeld, J. A. (2014). The fluid mechanics of carbon dioxide sequestration. Annual Review of Fluid Mechanics, vol. 46, pp. 255–272.

[3] Lindeberg, E. and Wessel-Berg, D. (1997). Vertical convection in an aquifer column under a gas cap of CO2. Energy Conversion and Management, vol. 38, pp. S229–S234.

[4] Riaz, A., Hesse, M., Tchelepi, H. A., et al. (2006). Onset of convection in a gravitationally unstable diffusive boundary layer in porous media. Journal of Fluid Mechanics, vol. 548, pp. 87–111.

[5] Ghesmat, K., Hassanzadeh, H., and Abedi, J. (2011). The impact of geochemistry on convective mixing in a gravitationally unstable diffusive boundary layer in porous media: CO2 storage in saline aquifers. Journal of Fluid Mechanics, vol. 673, pp. 480– 512.

[6] Chen, C. Y., Lin, T. S., and Miranda, J. A. (2016). Rotationally induced fingering patterns in a two-dimensional heterogeneous porous medium. Physical Review E, vol. 94, no. 5, p. 053105.

[7] Chen, C. Y. and Yan, P. Y. (2015). A diffuse interface approach to injection-driven flows of different miscibility in heterogeneous porous media. Physics of Fluids, vol. 27, no. 8, p. 083101.