An LCS approach to vortex pinch-off

When fluid is ejected out of a circular cylinder or nozzle, a boundary layer of vorticity forms inside the cylinder, and then separates at the edge of the cylinder and rolls up to form a vortex ring. Rings cannot grow indefinitely, but rather they stop accepting vorticity and 'pinch off.' This project involved using Lagrangian Coherent Structures (LCS) to robustly identify vortex ring pinch-off.

Publications

  • C. O'Farrell and J. O. Dabiri (2010). "A Lagrangian approach to identifying vortex pinch-off", Chaos: an Interdisciplinary Journal of Nonlinear Science (Focus Issue on Lagrangian coherent structures in fluid flows) Vol. 20, 017513.
  • C. O'Farrell and J. O. Dabiri (2009). "A Lagrangian approach to identifying vortex pinch-off", Bulletin of the American Physical Society Division of Fluid Dynamics Meeting. November 22-24, Minneapolis, MN.