CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Grid Independency Study

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 10, 2011, 05:55
Cool Grid Independency Study
  #1
Member
 
Join Date: Aug 2011
Posts: 33
Rep Power: 14
pchoopanya is on a distinguished road
Hey guys,

Hope people those are living in the UK are still able to run their simulations safely in their workplaces while the riots are happening all over the island. I am in Brighton and luckily there is no sign of these nonsense anti-social behaviour, not yet!

I am a newbie to CFD and Fluent. My research lies on CFD anyway, I am trying to run some demo simulations and grid independency study.

I use a simple hexahedral cell (a cube) and reduce the size until the results do not change with the further reduction of the cell's size - am I doign this correctly?

Let's say, if I have eventually come to the final minimum size that the results do not further change, with the exactly the same geometry, can I use this final cell size as a reference and then run other simulations but with different operating conditions (parametric study?) Or do I need to find the minimum cell size at every single simulation when the operating conditions are changed?

Sorry for my poor English if you cannot understand my words...



Cheers,

Pattarapong
pchoopanya is offline   Reply With Quote

Old   August 11, 2011, 00:09
Default
  #2
New Member
 
Calvin
Join Date: Aug 2011
Posts: 4
Rep Power: 14
Tongji Environment is on a distinguished road
Hi, in my opinion, there is a most appropriate grid density for one geometric model. Before the simulation, we should do grid independence research because the quality of grid can influence convergence speed and the computation precision.(the time consumpution of pre-process should take up 40% of the whole simulation)
You can create several models of different grid numbers with a certain proportion. Then go to caculate them respectively with the same condition setting. We can draw a curve with convergence iterations VS. grid density, choose the best one with the comprehensive consideration of accuracy and time requirement.
Once you choose a best grid density for a geometric model, you can use this grid to go to run other function simulations unless your geometric model will be changed.
May be useful for you!
Tongji Environment is offline   Reply With Quote

Reply

Tags
fluent, fluent 12.1, grid independence, mesh

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
how to do a grid independent study xyq102296 ANSYS 16 November 11, 2021 09:05
Grid Independent Study for a car John222 Main CFD Forum 1 January 26, 2011 20:05
About grid sensibilty study Fabio Main CFD Forum 0 October 15, 2009 12:23
Vorticity plot in grid refinement study CH Main CFD Forum 3 May 22, 2007 13:35
Combustion Convergence problems Art Stretton Phoenics 5 April 2, 2002 06:59


All times are GMT -4. The time now is 15:37.