Multiphysics Coupling of Dynamic Fluid Flow and Electromagnetic Fields for Subsurface Sensing

Nanoparticles designed with high electric conductivity and magnetic permeability are injected into oil reservoirs to enhance fluid flow monitoring. The movement of nanoparticles with the flow in a porous medium can be modeled by solving the flow transport equation. In this research, the three-dimensional spectral-element time-domain method based on Gauss-Lobatto-Legendre polynomials is employed to solve the fluid flow equation to obtain the nanoparticle (NP) concentration distribution in reservoirs. This method shows spectral accuracy, as the error decreases exponentially with the order of basis functions. The injected fluid with high contrast NPs increases the electric conductivity and magnetic permeability in the flooded zone, thus enhancing the electromagnetic (EM) signals in the receivers. Based on the coupling of the dynamic fluid flow and crosswell EM measurement, we are able to analyze the detection range of EM sensing with the high contrast NPs injection. The EM responses with different types of NPs injection are investigated under both an electric dipole and a magnetic dipole. The magnetic contrast NPs excited by a magnetic dipole source can generate a detectable signal while the electric contrast NPs can generate a detectable signal when excited by an electric dipole. The EM response of an inhomogeneous formation with a low permeable region shows that the signal at the producer near the barrier is lower than the other producers. The proposed multiphysics coupling technique of fluid flow and EM measurements can provide guidance for NPs field application and help monitor the flow movement in reservoirs.