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

Any Body got a Free Surface Solution in FIDAP

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

LinkBack Thread Tools Display Modes
Old   November 1, 1999, 14:13
Default Any Body got a Free Surface Solution in FIDAP
Dr. Ahmed Hassaneen
Posts: n/a
The velocity field and pressure have been solved successfully in Run # 1. When we solve for the FREE SURFACE (one FREE SURFACE) based on the previous run, the velocity and pressure just go crazy and the solution diverge rapidly with (N.R.) Solver. Also, some of the Node move to certain direction and the next one or two move to the oposite direction. Is there any advice????.
  Reply With Quote

Old   November 8, 1999, 13:43
Default Re: Any Body got a Free Surface Solution in FIDAP
Eric Grald
Posts: n/a
Dear Dr. Hasseneen,

I assume from your brief description that your initial mesh may be far away from the final free surface shape. Since the N.R. solver will make some large corrections to the mesh shape right away, it is quite possible that the calculation will diverge on the first iteration. It is also quite possible that there is an error in the setup of your free surface problem.

One way to get check this is to set the number of iterations to 1 and set the relaxation factor for the free surface to 0.99 or 0.999 (so that it won't change much). Then you should be able to obtain a solution for the first iteration. Take a look at this solution in FIPOST to make sure your problem setup is correct.

Please try this. If it doesn't help, please contact me directly at

Best regards,

Eric Grald
  Reply With Quote

Old   November 8, 1999, 15:59
Default Re: Any Body got a Free Surface Solution in FIDAP
Ahmed Hassaneen
Posts: n/a
Thanks Eric for your reply. The problem was in the PRBLEM definition, I was using STEADY and It should be TRANSIENT for the FREE SURFACE calculation. Is that correct?? I will send you the same message directly to you. Thanks Ahmed
  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
Can Flow-3D plot the free surface area in Iso-surface or colour variable? therockyy FLOW-3D 1 June 20, 2010 19:36
Free surface modelling under CFX 4 Dahong CFX 2 June 22, 2002 23:07
CFX 4.4 New free surface option Viatcheslav Anissimov CFX 0 April 3, 2002 06:27
Variable Density - Free Surface with FIDAP Vitaliy Pavlyk FLUENT 7 May 2, 2000 15:56
Radial jet with free surface using FIDAP Dr. Ahmed Hassaneen Main CFD Forum 0 October 28, 1999 13:20

All times are GMT -4. The time now is 00:47.