Large-scale structures of scalar and velocity in a turbulent jet flow

We study the relation between large-scale structures in concentration field with those velocity a dye-seeded turbulent jet. The scalar plane is measured using laser-induced fluorescence. Uniform zones of an advected are identified cluster analysis. simultaneously measure two-dimensional particle image velocimetry. characterized by finite-time Lyapunov exponents. measurement scalarand fields moves mean flow. In this moving frame, remain focus long enough to observe well-defined ridges field. This gauges rate point separation along Lagrangian trajectories; it was both for future and past times since instant observation. edges uniform correlated past-time field, but not future-time