A Method for Deriving Fluid-Structure Interaction Reduced-Order Models for Cerebral Aneurysms

A Reduced Order Modeling (ROM) method is discussed for Fluid-Structure Interaction problems in cerebral aneurysm. In this method, we first conduct training CFD simulations with pre-defined structural motion using the fixed mesh method, and then use the snapshot POD method to generate POD modes for both the flow field and the structure. Instead of using traditional topology-changing method, the CFD simulation is enhanced by a fixed mesh method to handle large-amplitude displacements or structural deformation without changing the mesh connectivity, thus consuming much less time. The POD ROM method is also enhanced by the same fixed mesh method, so that the training CFD simulation could be combined with the ROM smoothly. Besides, by implementing a fixed mesh method into the ROM, there is no need for iteratively calculating the forces acting on the structure for every time step. After generating POD modes for both the fluid and the structure using a fixed mesh, we couple these fluid and structure POD modes to create the FSI ROMs.