Interaction and "apparent" reconnection of 3D vortex tubes via direct numerical simulations

1988 ◽  
Vol 3 (1-4) ◽  
pp. 247-250 ◽  
Author(s):  
Melander V Mogens ◽  
Norman J Zabusky
Keyword(s):  
Numerical Simulations ◽  
Direct Numerical Simulations ◽  
Vortex Tubes

The Effect of Bubbles on Vortical Flows

2002 ◽  
Author(s):  
Jiacai Lu ◽  
Auturo Ferna´ndez ◽  
Gretar Tryggvason
Keyword(s):  
Simple Model ◽  
Numerical Simulations ◽  
Flow Rate ◽  
Model Problem ◽  
Velocity Profiles ◽  
Direct Numerical Simulations ◽  
Vortical Flows ◽  
Result Show ◽  
Vortex Tubes ◽  
Pressure Driven

The effect of bubbles on vortical flows near walls is examined by direct numerical simulations. A simple model problem, consisting of two slightly perturbed counter rotating vortex tubes plus a parabolic pressure driven velocity profiles is used. Initially, the flow is seeded with several bubbles near the wall. As the flow evolves, the bubbles are entrained into the vortices, where they accelerate the breakdown of the vortices. The flow rate and the wall shear is monitored and the result show that the presence of bubbles leads to a slight decrease in drag and thus an increase in flow rate.

Instability of strained vortex layers and vortex tube formation in homogeneous turbulence

1995 ◽  
Vol 282 ◽  
pp. 313-338 ◽  
Author(s):  
T. Passot ◽  
H. Politano ◽  
P.L. Sulem ◽  
J.R. Angilella ◽  
M. Meneguzzi
Keyword(s):  
Numerical Simulations ◽  
Vortex Tube ◽  
Three Dimensional ◽  
Quantitative Agreement ◽  
Finite Amplitude ◽  
Tube Formation ◽  
Direct Numerical Simulations ◽  
Homogeneous Turbulence ◽  
Tubular Structures ◽  
Vortex Tubes

A modulational perturbation analysis is presented which shows that when a strained vortex layer becomes unstable, vorticity concentrates into steady tubular structures with finite amplitude, in quantitative agreement with the numerical simulations of Lin & Corcos (1984). Elaborated three-dimensional visualizations suggest that this process, due to a combination of compression and self-induced rotation of the layer, is at the origin of intense and long-lived vortex tubes observed in direct numerical simulations of homogeneous turbulence.

Sign in / Sign up

Export Citation Format

Share Document