Traveling Viscosity Waves and Mild Viscous Fingering : the Unexpected Role of Shear Thinning Revealed by Data Driven Modeling of Shear-Thinning Polymer Flooding*

Modeling multiphase multicomponent immiscible porous media flows is a challenging task due to the interaction of interfaces and multiple simple and complex fluids of varying properties. We have developed a framework for incorporating shear thinning effects of polymer in a surfactant-polymer flooding simulator developed by Daripa and Dutta. The model, although is based on a very basic power law model, is data driven and implements the values of power-law coefficients empirically guided by the local values of concentration and shear rate. Since the concentration and shear rates are spatio-temporal variables, this model can predict physically accurate variable viscosity in the flow field based on local parameters. We demonstrate the importance of such a data-driven model and the potential it holds for improved modeling of polymer flooding to make an informed decision while choosing a polymer for a given flood simulation. Simulation reveals unexpected role of data driven shear thinning effect such as traveling viscosity waves and very mild viscous fingering, Participation of Rohit Mishra in simulating flows during early stages of this project is gratefully acknowledged.