Abstract
Hot water flushing experiments in a two-dimensional sandbox (35 cm × 20 cm × 1 cm) were conducted using dyed salad oil in single and two-layered porous formations under saturated conditions. Based on a calibration relation between the dye concentration and the corresponding pixel brightness an image processing technique in conjunction with spatial moments was developed to quantify not only the spatial distribution of oil but the apparent retardation and dispersion coefficients both in longitudinal and lateral directions. The increase of flooding water temperature resulted in accelerated downward movement of oil because of the reduced viscosity at elevated temperatures. The results also revealed that the variation of the apparent lateral dispersion coefficient depended on the oil saturation within a pore space and exhibited an increasing tendency in a smaller size porous material due to the difference of intrinsic permeability.
