|
[Sponsors] |
May 17, 2001, 15:47 |
Request Vortex Ring Data
|
#1 |
Guest
Posts: n/a
|
If you have or know someone who has DNS and/or experimental data on the evolution of a (fat) vortex ring subjected to azimuthal perturbations in its most unstable mode I would really appreciate a copy.
Thanks in advance Adrin Gharakhani |
|
May 18, 2001, 20:00 |
Re: Request Vortex Ring Data
|
#2 |
Guest
Posts: n/a
|
(1). How do you create a fat vortex ring? Is there any simple way to create such fat vortex ring? (2). Is it a steady-state process, or transient-state process? Is it inviscid? or viscous?
|
|
May 18, 2001, 21:25 |
Re: Request Vortex Ring Data
|
#3 |
Guest
Posts: n/a
|
Numerically, you can create anything you want; you should know better Experimentally, I'm not sure - a smoke puff coming off of a tube, whose cross-section is sinusoidally perturbed about a mean radius of a circle (to generate the initial perturbation)? I'm just guessing this is how it would be done.
As for the flow, it is definitely a transient process. A vortex ring propels under the influence of its own vorticity field. Not only that, because vorticity is perturbed initially (in its most unstable mode) the instability grows and a vortex ring that initially had no streamwise vorticity develops streamwise vorticies (3-D effects) and weak wakes behind the ring - kind of like the familiar mushroom cloud. This is an infinite Reynolds number problem, but NOT inviscid. I'd like to get some ideas about turbulent decay of energy and enstrophy (if possible). I'd say that the characteristics of the flow will probably be independent of the actual Reynolds number, so long as it is turbulent - the instability itself is inviscid, so a DNS result would be required to capture this process accurately. Adrin Gharakhani |
|
May 18, 2001, 23:03 |
Re: Request Vortex Ring Data
|
#4 |
Guest
Posts: n/a
|
(1). Thank you for the information. (2). So, it is more or less an idealized problem for the study of stability issue, I guess. (3). Is there any direct application of the result from this study?
|
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Vortex Lattice Method: Calculating lift using circulation from vortex ring elements | black&gold | Main CFD Forum | 11 | June 27, 2011 00:51 |
Air-Jet Vortex Generator, request for some papers | ROOZBEH | FLUENT | 0 | July 12, 2008 11:28 |
Air-Jet Vortex Generator, request for some papers | ROOZBEH | Main CFD Forum | 0 | July 12, 2008 11:27 |
request for the experimental data | Keshav Ram | Main CFD Forum | 0 | June 13, 2007 12:18 |
How to update polyPatchbs localPoints | liu | OpenFOAM Running, Solving & CFD | 6 | December 30, 2005 18:27 |