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

Negative Vorticity

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

LinkBack Thread Tools Display Modes
Old   April 27, 2009, 02:24
Default Negative Vorticity
New Member
Join Date: Apr 2009
Posts: 13
Rep Power: 10
student_58 is on a distinguished road
I want to learn that what negative vorticity means.İf vorticity is negative, what is hapening?...or what makes vorticity negative?
student_58 is offline   Reply With Quote

Old   April 27, 2009, 04:11
Dominic Chandar
Join Date: Mar 2009
Location: Singapore
Posts: 30
Rep Power: 10
dominic is on a distinguished road
Send a message via Skype™ to dominic
I believe its a relative term to indicate the direction of fluid rotation. You can use the right hand thumb rule to conclude that positive vorticity is related to counter-clockwise rotation of the fluid and negative vorticity is related to clockwise rotation of the fluid. As an example, consider the unseparated, laminar flow past a flat plate in the XY plane (from left->right): on top of the plate, you will find negative vorticity. You can imagine this negative vorticity as infinite number of cylinders rotating in the clockwise direction due to fluid moving towards the positive x-direction ( towards the right)...
dominic is offline   Reply With Quote

Old   April 27, 2009, 07:14
Join Date: Mar 2009
Posts: 44
Rep Power: 10
Timon is on a distinguished road
Vorticity is a vector and can therefore have an indefinite number orientations. In 2D the vector only has a component in the direction perpendicular to the plane. A positive value of this component indicates counter-clockwise and a negative value a clock-wise rotation (right hand rule). In 3D positive or negative only relates to one of the components of the vector (eg. spanwise component for a cylinder vortex shedding flow).
Timon is offline   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
negative element volume (CFX-10.0) CFDworker CFX 8 September 27, 2011 18:16
BlockMesh FOAM warning gaottino OpenFOAM Native Meshers: blockMesh 7 July 19, 2010 14:11
Vorticity Iso-Surface John Main CFD Forum 0 April 4, 2009 23:10
Contour plot with negative velocity J CFX 11 November 3, 2008 17:46
Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Native Meshers: blockMesh 10 April 2, 2007 14:00

All times are GMT -4. The time now is 00:03.