This method relies on defining multiple overlapping meshes, where the overset meshes “cut-out” bodies in the back ground mesh. For transient simulations, this technique can be used to model prescribed motion of a body or model free body interaction with the surrounding domain.
In this brief STAR-CCM+ video presentation, Clay Hearn, PhD, Senior Staff Mechanical Engineer at Applied Cax, introduces the techniques for setting up an overset mesh, provide a high level discussion of the theory behind the overset mesh, and show a couple examples of simulations with an overset mesh.