Visualization of Stirring Rods and Stirred Tank Flow by Digital In-line Holography

Abstract

This paper presents a method that uses digital in-line holography for the simultaneous visualization of stirring rods and stirred tank flow. This is achieved by dispersing two types of tracer particles, having different diameters, in the tank flow and rods, at a Reynolds number of 2810. By using this method, the three-dimensional velocities of both the tank flow and stirring rods can be individually visualized. Additionally, the cores of vortex tubes are visualized from the differences in specific gravity and refractive index between ethanol and an aqueous solution of sodium iodide.