Submodel in a Wheel Rim
Model ID: 8517
In stress analysis, it is common that the regions with high stresses are small when compared to the whole structure. Sometimes it is not feasible to have a mesh that at the same time captures the global behavior and resolves the stress concentrations with high accuracy. This is especially true in nonlinear or dynamic problems.
You can cope with this type of problems with a technique known as submodeling. First you solve the complete model with a mesh with is sufficient to capture the stiffness of the structure. In a second analysis you create a local model (submodel) of the region around the stress concentration with a fine mesh, and solve it using the displacements from the global model as boundary conditions. This example shows how to perform submodel analysis in COMSOL Multiphysics.