Kinetic interface sensitive tracers – Emerging smart tracer techniques for investigating the dynamics of fluid-fluid interfacial area in multiphase porous media systems

• Applicants: Professor Dr. Martin Sauter, since 9/2021; Professor Dr.-Ing. Holger Steeb
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428614366

The aim of this research is to develop the novel kinetic interface sensitive (KIS) tracer technique for studying and quantifying the dynamic evolution of fluid-fluid interfacial area (FIFA) and bring it closer to field application. As indicated in the letters of support, this proposal is closely linked to the current SFB1313 project at University of Stuttgart and contributes to their objectives. That is to improve the understanding how interfaces affect flow, transport and deformation processes in porous-media systems. By means of laboratory experiments and numerical modelling our work will aim at quantifying how the dynamics of fluid-fluid and fluid-solid interfaces in porous media systems are affected by pore geometry, heterogeneity and fractures. The work involves developing mathematical and computational models that describe the effective behaviour of porous-media systems including the effects of interfaces that occur on much smaller spatial scales.In this research we will develop an innovative, rapid, accurate technique for measuring the fluid-fluid interfacial area, the quantification of its dynamic production and evolution with time, and we will assess the potential of the KIS tracer technique in the parametrization of the fluid-fluid interfacial area production term, which is essential for the thermodynamic multiphase flow theories. This implies the following further detailed objectives: - Further development of the accuracy of the current methodology and the establishment of the KIS TT as a characterization technique for the determination of capillary pressure-saturation-specific interfacial area (p_c-S_w-a_wn) (WP1)- Investigation of the impact of grain size and surface roughness on the capillary-associated interfacial area and its interface production term (WP2.1A)- Development of an extended (macro-scale) interface condition including FIFA. (WP2.1B)- Expansion of the application of KIS tracers from one-dimensional column experiments to two-dimensional (2D) homogeneous and heterogeneous systems and, implicitly, 2D flow fields. (WP2.2A)- Application of the extended capillary pressure-saturation interface condition in 2D heterogeneous systems. (WP2.2B)- Development of new conceptual, mathematical and numerical models that allow the design of experiments and the interpretation of the experimental results (WP3)- Provision of a validation method for the numerical models by comparing them with experimental results. (WP4)

• DFG Programme: Research Grants
• Co-Investigator: Privatdozent Dr. Nikolaos Karadimitriou
• Ehemaliger Antragsteller: Dr.-Ing. Alexandru Bogdan Tatomir, until 8/2021