Implementation and validation of a slender vortex filament code: its application to the study of a four-vortex wake model

Abstract

A computational code EZ-vortex is developed for the motion of slender vortex filaments of closed or open shape. The integro-differential equations governing the motion of the vortex centrelines are either the Callegari and Ting equations, which are the leading order solution of a matched asymptotic analysis, or equivalent forms of these equations. They include large axial velocity and nonsimilar profiles in the vortical cores. The fluid may be viscous or inviscid. This code is validated both against known solutions of these equations and results from linear stability analyses. The linear and non-linear stages of a perturbed two-vortex wake and of a four-vortex wake model are then computed.