Introducing optimized validated meshing system for wellbore stability analysis using 3D finite element method

After studying different model sizes, mesh densities, element types, and boundary conditions, a cylindrical model consist of a combination of regular and irregular hexahedral elements for far-field region, and fine-grained tetrahedral elements for near-wellbore region was obtained. Two different approaches were selected for FEM modeling, in the first approach a pre-drilled well was considered in the model, and in the second approach the model geometry before drilling without a pre-drilled well was subjected to an initial state of stress, removal of the elements, and loading which simulate the drilling process using a certain mud weight. The results of simulating the state of strains around the wellbore using this meshing system in both FEM approaches had acceptable adoption with drilling data.