Abstract:
Abstract. This research investigates the relationship between optical density and liquid saturations in
unsaturated sand using multispectral image analysis technique. The tested liquids are water, diesel,
and parafin liquid. The experiments are performed on two-fluid phase systems (water-air, diesel-air,
and parafin liquid-air) and three-fluid phase systems (diesel-water-air and parafin liquid-water-air).
Water is dyed with Brilliant Blue FCF, whereas diesel and parafin liquid are dyed with Red Sudan III.
Using consumer-grade digital cameras, two images of sand specimens with various liquid saturations
are taken with two different band-pass filters. The analysis results show that, for the sand and
investigated fluids, the optical density defined for the reflected luminous intensity is a linear function
of the degrees of fluid saturation for each spectral band and for any two- and three-fluid phase
systems