The concept of tortuosity is used to measure and characterize the structure of porous media. Geometric tortuosity is the ratio between the shortest pathway in the medium to the distance between the inlet and outlet plane. Simple Neurite Tracer method is used to track the connected pores by tracing the tube structures of pores in 3D image stacks. In this analysis, the method is directly applied to the pore structure itself as well as the skeleton of the pores which represent the essential structure of the pore. The method is applied to four simple models of pores with different complexity levels, both the actual pore structure and the skeleton, to determine the effect of complexity to the tortuosity. The analysis is the applied on a digital sample of porous rock model with the size of 256 × 256 pixels. The interconnected pore for both the actual pore structure and the skeleton representation is traced by the Simple Neurite Tracer method. It was observed that the skeleton is a good representation of the actual pore because the pattern of tortuosity obtained between this two approaches are very similar. For all synthetic samples, the more complex the pore structure, the greater the tortuosity.
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