Molecular dynamics simulation of adsorption and diffusion of partially hydrolyzed polyacrylamide on kaolinite surface

Abstract

In tertiary oil recovery in oilfields, polymer solutions (partially hydrolyzed polyacrylamide) are often used for enhancing oil recovery. In view of the limitations of the current indoor flooding experiments, such as the limited scope of application and many assumptions, it is difficult to deeply reveal the mechanism of polymer flooding. In this paper, the molecular dynamics simulation method (MD) is used to establish an interaction model based on the construction of rock model, polymer molecular model and polymer solution system model to simulate the transport of polymers in nanopores from the microscopic level, and to study molecular. The interaction between them is described, and their diffusion and adsorption behaviors and viscoelastic properties are described, which provides a theoretical basis for the optimization of oil-displacing agents and the characterization of macro-rheological properties and flow parameters.