CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

hydrodynamics

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

Reply
 
LinkBack Thread Tools Display Modes
Old   March 17, 2001, 03:06
Default hydrodynamics
  #1
Zhou Yongcheng
Guest
 
Posts: n/a
I am simulating a driven cavity case with the upper lid moving towards right side while the bottom lid moving left. I supposed that there must be exact symmetrical and the result for low Reynolds showed this. But when Re goes higher, these are obvious in-symmetrical flow patterns. I try every means to deal with this but I failed. Then I think it may be cause by hydrodynamic instability and the in-symmetrical is physical. I am not sure of this. I would appriciate any explainations. Many thanks.

Zhou
  Reply With Quote

Old   March 17, 2001, 12:43
Default Re: hydrodynamics
  #2
John C. Chien
Guest
 
Posts: n/a
(1). It's hard to answer your question, because you did not state the essential information, such as the Reynolds number, the total mesh size and distribution, the numerical method used. (2). Some numerical methods are not stable and will produce oscillations when Reynolds number increases. (3). You can try the conventional "upwind" method and check your results again. It should be stable enough. (it might not be the most accurate method) (4). Once you have the solution, you can refine your mesh and improve your solution accuracy. (5). So, the suggestion is: refine your mesh and use upwind method. also try to use the steady-state method to see whether the solution is still oscillating or asymmetric.
  Reply With Quote

Old   March 18, 2001, 16:22
Default Re: hydrodynamics
  #3
Dean
Guest
 
Posts: n/a
You may find the following paper useful:

"Multiplicity of Steady Two-Dimensional Flows in Two-Sided Lid-Driven Cavities" by S. Albensoeder, H. C. Kuhlmann, and H. J. Rath, Theoret. Comput. Fluid Dynamics, vol. 14 (2001), pp. 223-241.
  Reply With Quote

Old   March 19, 2001, 09:24
Default Re: hydrodynamics
  #4
Zhou Yongcheng
Guest
 
Posts: n/a
Thank you very much!
  Reply With Quote

Reply

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
Ship hull hydrodynamics Costa Main CFD Forum 2 May 19, 2012 21:41
Smoothed-particle Hydrodynamics arien009 CFX 1 June 2, 2011 19:16
Hydrodynamics of High Density CFB Adnan FLUENT 1 February 13, 2010 22:23
Hydrodynamics Programming SUMAN KHAMRAI Main CFD Forum 0 July 18, 2005 12:13
Smoothed particle hydrodynamics amou Main CFD Forum 1 December 10, 1999 05:16


All times are GMT -4. The time now is 20:34.