Mineral reaction rates in porous media, i.e. precipitation and dissolution, usually exhibit spatial scaling effects. There is a tendency for apparent reaction rates to decrease as one moves from the pore scale through the laboratory scale to the field scale. Mathematical models at the Darcy scale are often incapable of capturing pore-scale reactive-transport processes. Understanding and quantifying these scaling effects is one of the central challenges in the field of subsurface reactive transport. Therefore, the Geothermal Energy and Geofluids Group at the Institute of Geophysics of the Department of Earth Sciences, ETH Zurich, Switzerland, invites applications for a
PhD position in hybrid modelling of mineral reaction rates in porous media
The objective of the project is to develop a hybrid model which comprises a Darcy-scale model, a pore-network model, and a pore-scale model. The underlying assumption is that the Darcy-scale (i.e. continuum-scale) model can be employed accurately in parts of the domain, but is invalid in other parts of the domain where, e.g., reaction rates are particularly high. In the latter case, a pore-network model would be used in those regions. In much the same way, a pore-scale model would be adopted in the parts of the pore network in which the common assumption of small variations of concentrations (or other quantities) is not valid. The simulator DuMuX will be used for the continuum-scale model and will also serve as a numerical framework for the hybrid model. Reaktoro will be used to calculate chemical equilibrium constants, activity coefficients, and kinetic rates.
A master’s degree in Geosciences, Engineering, Physics, Computer Science, or related field is essential. The candidate should have some programming skills as well as proven knowledge of developing/applying numerical models. Experience with DuMuX or Reaktoro is a considerable advantage. He/she should be proficient in English and have excellent scientific-writing and presentation skills. The maximum duration of the position is four years, pending a successful completion of the Research Plan Defence after one year. Benefits, working hours, salary, insurance, and pension are subject to ETH Zurich standards.