A model for non-Newtonian flow in porous media at different flow regimes

Hydrophobically associating polymers for enhanced oil recovery – Part B: A review of modelling approach to flow in porous media

“…A local maximum for the polymer viscosity is obtained at a third critical rate . Beyond , there is another decrease in polymer viscosity; this shear rate is characterized as the onset of mechanical degradation (Dupas et al, 2012;Brakstad and Rosenkilde, 2016;Lohne et al, 2017;Skauge et al, 2018). Polymer injectivity in porous media is influenced by a number of factors including shear thickening.…”

“…Due to the time-consuming nature of in-situ measurement techniques, in-situ polymer rheology has often been evaluated analytically and numerically (Skauge et al, 2018). The difficulty with modelling polymer rheology lies in the fact that they are non-Newtonian fluids and the porous media in which they flow is a non-uniform pore geometry (Lohne et al, 2017;Skauge et al, 2018). The analytical study of polymer flow in porous media involves the use of time-independent models with the addition of some viscoelastic attributes (Delshad et al, Journal Pre-proof J o u r n a l P r e -p r o o f 2008; Sochi, 2010;Hatzignatiou et al, 2013;Yang et al, 2015).…”

“…The thinning and thickening respectively. According to Lohne, et al (2017), the polymer relaxation, time can be related to both polymer properties (molecular weight, , polymer concentration, and specific viscosity, ) and reservior conditions (temperature, and salinity by modifying the slovent viscosity, ) as shown in equation 12…”

“…In summary, the use of relaxation time alone in calculating the onset of shear thickening is not sufficient if the stretch rate cannot be estimated. Accordingly, Lohne et al (2017) reported that the use of in describing the onset of shear thickening is limited as it only captures the Journal Pre-proof J o u r n a l P r e -p r o o f 24 insufficient relaxation time required to recover from its deformation arising from the previous pore throat entry. The reason for the adoption of for predicting shear thickening is that the events of insufficient relaxation time for recovery and the characteristic time for flow in a pore entrance are assumed to be close (Lohne, et al, 2017).…”

“…However, flow in rheometers or viscometers represents a different geometrical configuration to a porous media. The flow of polymers in a porous media can be attributed to the existence of both shear and extensional components (Sochi, 2010;Stavland et al, 2010;Zamani et al, 2015;Lohne et al, 2017;Zamani, et al, 2017;Skauge et al, 2018). In differentiating between these components, Figure 2 shows a fluid element (A) subjected to both shear and extensional flow.…”