Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2017 - September 06, 2017
This study numerically investigates the mixing of a two-layer density stratified fluid caused by vortex rings. Initially, the density-stratified fluid is in a static condition in a tank. The upper and lower fluids are glycerol aqueous solution and an aqueous solution of potassium dihydrogen phosphate, respectively. Two vortex rings are arranged on a vertical line in the lower fluid, and the axial interval is 80 mm. The diameter of the vortex ring is 26.4 mm, and the Reynolds numbers based on the circulation are 4000, 6000, and 8000. The vortex rings are launched simultaneously in the vertically upward direction. The simulation explores the collision of the vortex rings with the density interface, the entrainment of the fluids into the vortex rings, and the resulting mixing between the fluids. It also clarifies the behavior of each vortex ring, such as the deformation and the interaction with the density interface.