Models for quantification of aperture in a rough walled fracture bioclogging system with the light transmission method

Based on the light transmission method in quantification of aperture in a rough wall fracture bioclogging system and its application in a two-phase flow system, one group of 2-D rough wall fracture modeling device was developed to study the migration of microbes in a fracture groundwater system, and quantification of the variation in aperture and its distribution by bioclogging. The experiment results indicate that the most of the microbes exist in the form of clusters and do not form the obviously continuous biofilm. The microbes randomly occur in different spatial locations, however, they mainly appear in the bottom area of the fracture, which is controlled by the ways of microbes inoculation and nutrient injection. The average aperture of the fracture is reduced by bioclogging (from 1.181 μm to 1.086 μm with the percentage of 8.04). Meanwhile, the apertures located at different points (except two individual points), where apertures are calculated with the light transmission method, decrease during the process of microorganisms growth. Point 2 has the greatest reduction of 194 μm in aperture (from 1.275 μm to 1.081 μm) with the percentage of 15.22. The light transmission method is an effective and non-destructive monitoring method used in labs. It can be applied to the bioclogging, especially in the study of quantification of biofilm in fracture, which is of significant reference value in the related research work for bioclogging in fracture.