A 3-D velocity measurement was carried out via LDV for vortex breakdown of swirling flow in a closed cylindrical container with a rotating disk. The experimental results of swirling flow at Ar=1.78 and Re=648-2527 are...A 3-D velocity measurement was carried out via LDV for vortex breakdown of swirling flow in a closed cylindrical container with a rotating disk. The experimental results of swirling flow at Ar=1.78 and Re=648-2527 are presented. At the axis, the axial velocity variation with Re describes the formation, development and disappearance of the vortex breakdown, which agrees with Escudiers's conclusion. In the meridional plane, the velocity vectors show that the bubble type vortex breakdown region is a closed and low velocity circulating flow, which is fully isolated from the main flow thrown out by the rotating disk. For the peripheral velocity in the central region of the container, the maximum does not appear near the rotating top disk but near the stationary bottom disk and it varies sharply there. Numerical simulation results under the same conditions are also given in this paper.展开更多
文摘A 3-D velocity measurement was carried out via LDV for vortex breakdown of swirling flow in a closed cylindrical container with a rotating disk. The experimental results of swirling flow at Ar=1.78 and Re=648-2527 are presented. At the axis, the axial velocity variation with Re describes the formation, development and disappearance of the vortex breakdown, which agrees with Escudiers's conclusion. In the meridional plane, the velocity vectors show that the bubble type vortex breakdown region is a closed and low velocity circulating flow, which is fully isolated from the main flow thrown out by the rotating disk. For the peripheral velocity in the central region of the container, the maximum does not appear near the rotating top disk but near the stationary bottom disk and it varies sharply there. Numerical simulation results under the same conditions are also given in this paper.