Deformation of a Compact Oil Patch at a Compound-Vortex Surface

The deformation of a compact patch of immiscible fluid introduced into the cavity-surface center of the compound vortex has been reported. Oil spills represent an ever increasing danger for the ecology of the entire hydrosphere and, especially, the World Ocean due to the steadily growing volumes of oil sea extraction and transportation. The soluble dye patch introduced into the center or an arbitrary point on the cavity surface was extended into the pointed spiral arms separated by clear water bands. The rotating disk formed an axisymmetric composite vortex flow in the cylindrical container. The uniformly rotating disk gradually involves the entire fluid layer into an axisymmetric flow around the vertical axis. The flow patterns were recorded by a digital photo camera and video cameras placed before and above the installation. The thin spiral arms enveloping the central patch by several coils are also extended from the external edges of the ledges.