Abstract
In this thesis we investigate methods preserving the effects of thin layers of rock with low permeability on flow behaviour while upscaling geological models of porous media. More specifically, we study this upscaling in the context of upward migration of CO2 in the process of Carbon Capture and Storage (CCS).
Three methods are implemented and investigated. The first method consists of harmonic averaging the permeability onto coarser grids. This is proven to be an insufficient choice for upscaling. The second and third methods rely on computing appropriate permeability and transmissibility fields respectively on coarse grids based on the reservoir and rock’s geophysical parameters. An analysis of the fields’ dependence on these parameters is conducted for each method. This analysis concludes that both methods, although generating a flow similar to the flow observed on a fine grid in specific cases, can potentially lead to errors in flow behaviour modelling and must thus be used with caution.
