Dynamic evolution of vortex dipoles

Abstract

Vortex dipoles are fundamental in fluid mechanics. They are found in geophysics, engineering and industry. The two necessary conditions to generate them are a plane flow and a generating force. In this work, an experimental design to generate vortex dipoles in stratified beds is presented. Vortex rings were generated under different volumetric flow conditions. Through visualization techniques, three stages were observed during the evolution of the rings: an exponential stage associated with the injection of the tracer, a parabolic stage and finally a dissipative stage. From the experimental results, the Reynolds and Péclet numbers were computed indicating laminar flows and diffusive flows, respectively. © The Sociedade Brasileira de Física.