Development of the governing equation on the behavior of radial flows in coarse porous media and its numerical solution

The hydrous bed of the rivers covered with coarse alluvial materials is a good resource along with other resources to provide the needs of the water. Therefore, studying and investigating the flow behavior around wells excavated in these beds and determining their discharge capacity is very important. Since the flow to the wells is radial and previous research on coarse, porous media, there has been mainly for parallel flows, and yet any equation replacing the Laplace relationship in coarse, porous media, is not provided for non-Darcy radial flows with a free surface, Therefore, the extraction of the differential equation ruling on these types of flows in the cylindrical coordinates and a method for numerical solution of them in this research has been followed. Based on the research carried out in this research, the power (exponential) equation as the most suitable basic relation for the analysis of radial flows was determined and used. Also, in order to solve the governing equations a numerical model was developed using finite volume method. The developed numerical model act well for the analysis of radial flows in the coarse alluvial beds. The results of the implementation of the numerical model indicate that the pressure distribution can be considered hydrostatic.