Persistence Problem in Two-Dimensional Fluid Turbulence
Persistence Problem in Two-Dimensional Fluid Turbulence
We present a natural framework for studying the persistence problem in two-dimensional fluid turbulence by using the Okubo-Weiss parameter $\ensuremath{\Lambda}$ to distinguish between vortical and extensional regions. We then use a direct numerical simulation of the two-dimensional, incompressible Navier-Stokes equation with Ekman friction to study probability distribution functions (PDFs) of …