Calibrating and interpreting implicit-texture models of foam flow through porous media of different permeabilities

This paper proposes a robust methodology to calibrate steady-state models of foam flow through porous reservoirs from foam displacements on core samples. The underlying approach consists in linking foam mobility and foam lamellas density (or texture) at local equilibrium. This calibration methodology is applied to foam displacements at different qualities and velocities on a series of sandstones of different permeabilities. Its advantages lie in a deterministic non-iterative transcription of flow measurements into texture data, and in a separation of texture effects and shear-thinning (velocity) effects. They are discussed with respect to calibration methods that consist in a least-square fit of apparent viscosity data. Scaling trends of foam parameters with porous medium permeability are then identified and discussed with the help of theoretical representations of foam flow in a confined medium. Although they remain to be further confirmed from other well-documented experimental data sets, these scaling laws can increase the reliability of reservoir simulators for the assessment of foam-based improved recovery processes in heterogeneous reservoirs.