# Vortex methods for three-dimensional separated flows

## Abstract

Traditionally, vortex methods have been used to model unsteady, high Reynolds number incompressible flow by representing the fluctuating vorticity field with a few tens to a few thousand Langrangian elements of vorticity. Now, with the advent of fast vortex algorithms, bringing the operating count per timestep down to O(N) from O(N^{2}) for N computational elements, and recent developments for the accurate treatment of viscous effects, one can use vortex methods for high resolution simulations of the Navier-Stokes equations. Their classical advantages still hold - (1) computational elements are needed only where the vorticity is nonzero (2) the flow domain is grid free (3) rigorous treatment of the boundary conditions at infinity is a natural byproduct and, (4) physical insights gained by dealing directly with the vorticity field-so that vortex methods have becbrhe an interesting alternative to finite difference and spectral methods for unsteady separated flows.

## Keywords

Bluff Body Vorticity Field Computational Element Vortex Method Infinite Domain## Preview

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