Direct numerical simulation of vortex ring evolution from the laminar to the early turbulent regime

Direct numerical simulation is used to study the temporal development of single vortex rings at various Reynolds numbers and core thicknesses. Qualitative differences between the evolution of thin- and thick-core rings are observed leading to a correction factor to the classical equation for the rin...

Full description

Bibliographic Details
Main Authors: Archer, P.J (Author), Thomas, T.G (Author), Coleman, G.N (Author)
Format: Article
Language:English
Published: 2008-03.
Subjects:
Online Access:Get fulltext
LEADER 01520 am a22001453u 4500
001 52010
042 |a dc 
100 1 0 |a Archer, P.J.  |e author 
700 1 0 |a Thomas, T.G.  |e author 
700 1 0 |a Coleman, G.N.  |e author 
245 0 0 |a Direct numerical simulation of vortex ring evolution from the laminar to the early turbulent regime 
260 |c 2008-03. 
856 |z Get fulltext  |u https://eprints.soton.ac.uk/52010/1/direct_numerical_simulation_of_vortex_ring_evolution_from_the_laminar_to_the_early_turbulent_regime.pdf 
520 |a Direct numerical simulation is used to study the temporal development of single vortex rings at various Reynolds numbers and core thicknesses. Qualitative differences between the evolution of thin- and thick-core rings are observed leading to a correction factor to the classical equation for the ring translational velocity. We compare the obtained linear modal growth rates with previous work, highlighting the role of the wake in triply periodic numerical simulations. The transition from a laminar to a turbulent ring is marked by the rearrangement of the outer core vorticity into a clearly defined secondary structure. The onset of the fully turbulent state is associated with shedding of the structure in a series of hairpin vortices. A Lagrangian particle analysis was performed to determine the ring entrainment and detrainment properties and to investigate the possibility of an axial flow being generated around the circumference of the core region prior to the onset of turbulence. 
655 7 |a Article