An experimental study of flow surrounding the migration of two forced-point-vortices.

Vortex interaction and merging appear in several natural phenomena. This study explores the collision and merging of two point-like vortices generated by magnetic stirrers. These stirrers are independently operated by four motors and are located at the base of a shallow layer of water with a free surface. The objective is to identify the hydrodynamic conditions that result in the collision and merging of the two vortices, which have varying speeds and angular velocities. The study utilizes the Particle Image Velocimetry method to analyze the resulting flow patterns and comprehend the process of merging of the two vortices and the consequent flow dynamics.