# Transform N-S equations.

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

 February 19, 2011, 17:56 Transform N-S equations. #1 Member   Paul Zhang Join Date: Feb 2011 Posts: 44 Rep Power: 8 Sponsored Links Is there anyone know how to transform the N-S equation, which is steady in (x,y) coordinates to time dependent in (Epsliong, Etta) coordinates. Maybe that is a transform from Euler to Lagrange. But I do not know how. Any idea will be greatly appreciated. I thought about it for quite a long time.

February 21, 2011, 10:50
#2
Member

Shenren Xu
Join Date: Jan 2011
Location: London, U.K.
Posts: 63
Rep Power: 8
The basic idea is simply coordinate transformation (or, should I say, chain rule). If you have never done it before, it's very tricky to get every term right.

Most textbooks give you results on orthogonal curvilinear coordinates, which should be enough if your coordinate system is orthogonal. Otherwise, you'll need a more general result, you may need to derive them by hand, a good starting point is the wikipedia link on curvilinear coordinates.

http://en.wikipedia.org/wiki/Curvilinear_coordinates

Quote:
 Originally Posted by paulzhang Is there anyone know how to transform the N-S equation, which is steady in (x,y) coordinates to time dependent in (Epsliong, Etta) coordinates. Maybe that is a transform from Euler to Lagrange. But I do not know how. Any idea will be greatly appreciated. I thought about it for quite a long time.

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post pete Site Help, Feedback & Discussions 20 June 16, 2015 13:52 afroz_javed OpenFOAM 1 January 20, 2011 06:25 tstorm Fluent UDF and Scheme Programming 1 January 11, 2010 14:04 tstorm FLUENT 1 January 11, 2010 14:02 ff_fan Main CFD Forum 1 September 20, 2002 07:39