Fluid-structure interaction using mesh-free modelling

Abstract

Fluid-structure interaction (FSI) concerns the multi-physics dynamics of an immersed structure interacting with its surrounding fluid. Presented here is a model that can be used to evaluate the effects of forced wall motions on a bounded viscous flow. This is analogous to boundary-layer control strategies such as those employing micro-electro-mechanical (MEM) devices to modify boundary-layer dynamics.The model employs a 2-D mesh-free Lagrangian scheme that combines the discrete-vortex method (DVM) and boundary-element method (BEM) to model a boundary-layer over a surface of arbitrary deformation. To overcome the “N-body” O(N2) scaling issues associated with the DVM and other Lagrangian methods an efficient Fast Multipole Method (FMM) is utilised. Key features of the model include viscous diffusion via the Corrected-Core-Spreading method, dynamic vortex blob “re-gridding” and a strictly enforced no-slip condition via vorticity injection at the wall. It is shown that the model is developed with sufficient flexibility to be used to simulate compliant-wall interactions with boundary-layer flows.