CFD Online Logo CFD Online URL
Home > Forums > FLUENT

How many time steps should I use?

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

LinkBack Thread Tools Display Modes
Old   July 19, 2002, 00:09
Default How many time steps should I use?
Posts: n/a
Hello all,

I am simulating an unsteady, laminar flow in Fluent. I have determined the smallest time scale and am using a time scale which is 1/10th of this as my time step. How do I determine the number of steps that I need though? Is this based on the residence time of the fluid (I have flow in a channel with obstacles in it- so must I take length of channel/velocity as my total time to get an accurate solution?)

Thanks. Dhananjay
  Reply With Quote

Old   July 19, 2002, 09:20
Default Re: How many time steps should I use?
Posts: n/a
--make sure you have good initial conditions (e.g. from a steady calculation)

--choose a time step as such that you have a large residual-drop within each time-step in 20-30 iterations per time-step.

--leave it running

good luck,

Laika, still orbiting
  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
Multiple floating objects CKH OpenFOAM Running, Solving & CFD 12 March 21, 2016 14:05
calculation diverge after continue to run zhajingjing OpenFOAM 0 April 28, 2010 04:35
Convergence moving mesh lr103476 OpenFOAM Running, Solving & CFD 30 November 19, 2007 15:09
UDF for time steps David FLUENT 0 August 14, 2007 11:54
Time steps - Large Eddy - LES Gernot FLUENT 0 September 14, 2005 11:54

All times are GMT -4. The time now is 09:50.