複数の渦輪による密度成層流体の混合の数値シミュレーション

抄録

This study numerically investigates the mixing of a two-layer density-stratified fluid caused by two vortex rings. Initially, the density-stratified fluid is in a static condition in a rectangular tank. The upper and lower fluids are glycerol aqueous solution and an aqueous solution of potassium dihydrogen phosphate, respectively. The density ratio is 1.015. Two vortex rings are arranged on a vertical line in the lower fluid. The Reynolds number, based on the circulation, ranges from 4000 to 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 collapse.