A numerical simulation of vortex breakdown

A numerical simulation of vortex breakdown using the time-dependent Navier-Stokes equations is performed. Unlike previous studies, the numerical algorithm, formulated in terms of the velocity and vorticity, is not restricted by axisymmetry conditions. The vortex is parameterized in terms of the Reynolds number and Rossby number. The resulting breakdown structure is analyzed using contour plots of velocity, vorticity and pressure as well as axial, radial, and swirl velocity profiles at various streamwise locations. The relationship of these results to experimentally observed structures and previous numerical results is discussed.