D. Fabris et al., QUANTITATIVE EXPERIMENTAL AND NUMERICAL INVESTIGATION OF A VORTEX RING IMPINGING ON A WALL, Physics of fluids, 8(10), 1996, pp. 2640-2649
A joint experimental and computational methodology is developed and ap
plied to investigate a vortex ring impinging normally on a wall. The m
ethod uses digital particle image velocimetry to make planar flow meas
urements, which are then used to initialize a second-order finite diff
erence calculation. The experiment and the simulation are compared at
later times and agree extremely well. The ring undergoes two rebounds
from the wall and continues to expand. During the approach to the wall
, peak vorticity grows by 50% due to vortex stretching. Peak vorticity
strengths of the secondary and tertiary vortices formed from the shed
ding boundary layer are 40% and 20% of the primary. In addition, a rin
g with a Gaussian core is simulated and compared to demonstrate the be
nefits of using realistic initial conditions. (C) 1996 American Instit
ute of Physics.