Mechanism study and formula development by numerical simulation and visualization experiment in a microfluidic system for enhanced oil recovery

In this study, microfluidic system was adopted to investigate the effects of hydrodynamic factors on chemical flooding. The combination of visualization experiments and computational fluid dynamics (CFD) simulations was used to evaluate the effects of flow rate, interfacial tension (IFT), viscosity, density, contact angle and porosity on EOR (enhanced oil recovery). The chemical flooding regulation model was built through dimensional analysis of hydrodynamic factors, affording oil displacement empirical formula for oil displacement by fitting EOR data. The empirical formula displayed high applicability within a certain range of capillary number (Ca), oil–water density ratio and porosity. In addition, the empirical formula was expected to guide the development of a cardanol-based surfactant, whose preparation process was optimized in the microreactor. These findings would provide useful references for understanding the EOR mechanism of chemical flooding at micro-scale.