CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Time dependent solution

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

LinkBack Thread Tools Display Modes
Old   January 10, 2004, 10:24
Default Time dependent solution
Posts: n/a
I try to simulate a naturally ventilated building with small openings in its sides. Air blows from an inlet far away from the building, enters through one side opening and leave through the opposite opening and also I have a recirculation of air in the space above openings. Heat and mass (H20) transfer are also taken into account. After a few iterations (2000) I have a converged solution with logical values for air velocity temperature and humidity inside the building. Then I try to see what happens if I patch in the area inside the building higher (than outside air) values for humidity and temperature. I turn the solver to unsteady I patch higher values for humidity and temperature and I sellect a time step of 0.01. Each time step needs less than 20 iteration to converge. But although at the first 3000 time steps I have the same (with the steady solution) airflow pattern inside the building after this point the airflow pattern is different onlyy in the area above the opneings. That means that above openings I dont have a recirculation of air like in the steady solution and the values of air velocty are very low. Any suggestions? Thank you in advance Thomas
  Reply With Quote

Old   January 13, 2004, 10:12
Default Re: Time dependent solution
Posts: n/a

Don`t you think that time step of 0.01 s is a little to small for your case. Can you really get much change in 3000 time steps (30 s in your case)?

  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
Moving mesh Niklas Wikstrom (Wikstrom) OpenFOAM Running, Solving & CFD 122 June 15, 2014 06:20
How to write k and epsilon before the abnormal end xiuying OpenFOAM Running, Solving & CFD 8 August 27, 2013 15:33
Transient simulation not converging skabilan OpenFOAM Running, Solving & CFD 12 September 17, 2007 17:48
Time Dependent Solutions. rakib FLUENT 2 June 28, 2000 07:39
Implicit vs. Explicit Praveen C. Main CFD Forum 1 December 14, 1999 10:35

All times are GMT -4. The time now is 00:23.