Surface-forces on deforming geometries using Vortex Methods and Brinkman penalization

摘要: We present numerical methods for determining flow-induced forces on the surface of rigid and deforming bodies, when using vortex methods [1] combined with Brinkman penalization [2]. The procedure outlined is shown to perform well for two-dimensional impulsively started cylinders at Re= 550 and 1000, as well as for self-propelled swimmers at Re= 400 and 4000. The interaction between fluid-flow and complex solid geometries is accounted for by enforcing the no-slip boundary condition using Brinkman penalization. The pressure-induced and viscous components of the surface-forces are considered separately when computing the flow-induced forces. The pressure field is recovered from the velocity by solving a Poisson equation. The discrete convolution involved is solved using a fast tree-code algorithm, based on multipole expansion [3] of the Green’s function for the Laplacian. The viscous forces acting on …