Creation of Saturation Maps from Two-Phase Flow Experiments in Microfluidic Devices

Microfluidic devices provide an experimental platform for direct observations of flow in complex channel networks. In this work, two-phase displacement experiments are conducted using a microfluidic device, featuring a complex network that is representative of a sample of Berea sandstone. The porous medium is placed in the field of view of a high-resolution camera with a monochromatic sensor—data captured in the form of images cover the entire medium while maintaining the resolution needed to discern features as small as 10 μm. This paper presents the series of steps required to convert these images into saturation maps that may be used for comparisons with predictions of numerical simulation models. The main steps include: exclusion of the grains; perspective transformation to correct minor misalignments of the device in each experiment; calculation of the Representative Elementary Volume; local thresholding strategy to account for non-uniform illumination across the medium; and finally, calculation of saturation maps.