Flow in geological materials

Fluids in pores and near the interfaces with solids have a controlling role in Nature, e.g. in the formation and weathering of rocks, in erosion and mobilisation of deposits and for movement of water in aquifers and oil in reservoirs. Understanding these processes is essential for making informed decisions about how to solve some of society’s challenges, such as contaminant remediation of soil and groundwater and for underground storage of CO2. SOLID’s partners are pioneers in flow modelling at micrometre scale using 3D X-ray images (figure). Methods exist for quantifying and modelling fluid flow over the centimetre to the aquifer scale but currently, the macroscopic models cannot integrate to the molecular scale because we lack understanding about the processes that control behaviour in the range from centimetre to nanometre. Our goal is to build a bridge, by combining flow modelling with 3D images made using neutrons and X-rays. SOLID gives a completely unique possibility for coupling length and time scales and to test the new methods by using the lighthouse facilities. Some examples include comparison of model results with data from experiments under the conditions of temperature and pressure that represent Denmark’s underground. Research in SOLID will improve models for predicting the spread of contaminants, the success of remediation and possible scenarios for geologic storage of CO2.

The Figure is chalk from off-shore drilling in the North Sea region presented in the article by Misztal Marek, Hernandez-Garcia Anier, Matin Rastin, Müter Dirk, Jha Diwaker, Sørensen Henning, Mathiesen Joachim called Simulating anomalous dispersion in porous media using the unstructured lattice Boltzmann method  published in 2015 in Frontiers in Physics. The left side of the image is showing the surface plot of the investigated volume of the sample, colored according to the surface velocities. The values on the solid boundary are at least three orders of magnitude lower than the values on the outlet (top surface of the mesh). On the right image are the streamlines of the steady-state velocity field, generated for τ = 0.02, Δρ = 2.5.10 ^-6. Both images were generated using ParaView 4.3.1.