Dye Transport Pattern in Compound Vortex Flow

Abstract Shapes of deformed water surface and transport of dyes in compound vortex flow are studied experimentally. Vortex motion is produced by rotating disc at the bottom of vertical cylindrical container. Strong anisotropy of substance transport from a compact spot in compound vortex is traced. In a fluid at rest drop of dye placed on a free surface forms cascade of circular vortices in the water depth. Drop of dye placed on curved surface of compound vortex is transformed into fast changing heli- cal structures. On the free surface extended spiral arms are span up from initial spot. Dye from surface spot is also extracted into liquid body and transported along so-called ‘dye walls’ inside compound vortex. Structure stability of the flow pattern is discussed.