Dynamic programming analysis of pore space

A method based on the principles of dynamic programming is developed and applied to digital soil images to determine tortuosity, effective porosity, and the shortest paths available for flow. Pathways for flow are determined by minimizing a resistance factor. Analysis of two numerically simulated soils finds that a platy soil has greater effective porosity and smaller tortuosity than a layered soil. The ability of the dynamic programming model to analyse large digital images with complex pore structure is subsequently demonstrated by the analysis of a digital image of an agricultural soil. The results from the agricultural soil point to the need for digital soil image analysis to be three-dimensional if convective and diffusive soil properties are to be examined. It is demonstrated that, because determination of flow paths can be treated as a routing problem solved by applying a few simple rules, dynamic programming analysis is not limited by complexity of pore structures.