title: Long-time simulations of the Kelvin-Helmholtz instability using an adaptive vortex method.
abstract: The nonlinear evolution of an interface subject to a parallel shear flow is studied by the vortex sheet model. We perform long-time computations for the vortex sheet in density-stratified fluids by using the point vortex method and investigate late-time dynamics of the Kelvin-Helmholtz instability. We apply an adaptive point insertion procedure and a high-order shock-capturing scheme to the vortex method to handle the nonuniform distribution of point vortices and enhance the resolution. Our adaptive vortex method successfully simulates chaotically distorted interfaces of the Kelvin-Helmholtz instability with fine resolutions. The numerical results show that the Kelvin-Helmholtz instability evolves a secondary instability at a late time, distorting the internal rollup, and eventually develops to a disordered structure.
authors.affiliation: Department of Mathematics, Kangnung-Wonju National University, Kangnung 210-702, South Korea.
authors.forename: Sung-Ik
authors.initials: SI
authors.lastname: Sohn
authors.forename: Daeki
authors.initials: D
authors.lastname: Yoon
authors.forename: Woonjae
authors.initials: W
authors.lastname: Hwang