2010 Volume 76 Issue 772 Pages 2143-2151
Ultrasound Velocity Profiler (UVP) is applied to measurement of two-dimensional velocity vector field of vortex rings in water. The instantaneous flow field passing through the measurement section is reconstructed from spatio-temporal distribution of velocity component obtained along two different ultrasound measurement lines. The method of reconstruction is valid when vortex rings have axisymmetric structure having constant translational velocity at the measurement section. Using this principle, vortex ring subject to background rotation is also presented to discuss the effect of weak Coriolis force on formation process of vortex rings.