CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

turbulent eddie

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   October 8, 1998, 07:01
Default turbulent eddie
Posts: n/a
hello all

thanks a lot for your attention. I need (long) time to learn !... :>

I'd like to ask again about turbulent eddie :

1. As Jonas & Prabhu said, turbulent eddie is small & vortex can be a large scale structure. I read that there is large scale eddie (contained most kinetic energy) how about that? Can we see the turbulent eddie?

2. I saw the paper about simulation of fluid flow in combustion engine chamber. There were rotasional structure called swirl and tumble. Are these vortex or turbulent eddie (the flow was turbulent) ?

that's all thanks again for the answers



  Reply With Quote

Old   October 8, 1998, 12:28
Default Re: turbulent eddie
John C. Chien
Posts: n/a
1). If you take a long-time exposure photo of a turbulent flow , you get sort-of time-averaged flow picture,that is the mean flow picture. 2). If you move the camera at the mean flow speed, those turbulent eddie moving at the mean flow speed will be stationary, relative to the camera, and you will be able to see the structure of these eddie. 3). If you move the camera at a lower speed, you will see only those eddie moving at this lower speed. You will not be able to see the structure of those eddie moving at the mean flow speed at this lower camera speed. 4). Swirl and tumble motion are mean flow motion, which is equivalent to the long-time exposure photo of the flow in a combustion chamber. 5). Swirl and tumble ( rotational motion in two different axis ) are used in the IC engine design to improve mixing and combustion efficiency.
  Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
CFX Treatment of Laminar and Turbulent Flows Jade M CFX 14 June 15, 2016 09:36
Turbulent Boundary Layer on a Flat Plate Hoshang Garda FLUENT 1 November 27, 2013 11:24
Turbulent Dispersion for Coal Combustion gravis CFX 2 March 24, 2010 00:56
setting value of turbulent intensity and turbulent viscosity ratio in wind tunnel nuimlabib Main CFD Forum 0 August 4, 2009 00:05
Problem of Turbulent Viscosity Ratio Limited David Yang FLUENT 3 June 3, 2002 06:13

All times are GMT -4. The time now is 23:49.