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

modelling a classroom using Airpak!

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 20, 2005, 17:30
Default modelling a classroom using Airpak!
  #1
Amid
Guest
 
Posts: n/a
can we post here our questions about Airpak?

i am modelling a classroom (8.4 X 7.2 m) uses DV, the process is domianted by natural convection which is the source of the problem. Since natural convection was heavily dominated in my problem, i would have had no choice but to use Transient to capture the physics of problem (even though the problem itself is steadystate), which brings me to my next quetion ==> is there any ways to achive convergence by playing around with the URF, where tdo i start??

my last question is about results, i am comparing my model to experimental data, my results agree with the measured data at all points except at floor level (0.1 m). all my 12 points at the floor level is off by approx 2-3 C. i know that for a realistic solution we need to use the Low-reynold number near wall areas, and iam guessing airpak uses the Law of Walls coupled with the standard k-e to get results. i have placed the first grid at the distance of 10mm from the wall. i need however to verify that iam not meshing the viscous sublayer, so i need y+. Is there anyways to make airpak give the value for y+??

i was wondering for a typical DV problem for a office what should the the typical the convergence critrea, for somereason i dont think Airpak's pre-define convergence critrea is enough for a problem with natural convection

what should the the typical discrepency percentage between experimental and CFD

thanks
  Reply With Quote

Reply


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
Modelling unsteady 2D aerofoil drag xlxc34 Main CFD Forum 0 June 24, 2011 05:42
Advice on multi-phase flow modelling Martin Main CFD Forum 3 October 14, 2008 06:16
Unsteady modelling technique? Carlos FLUENT 0 September 26, 2008 12:37
how to ensure that your modelling is correct rvndr Main CFD Forum 7 March 1, 2004 13:21
Computational Modelling of Vortex Separators May Lim Main CFD Forum 6 November 13, 1998 13:36


All times are GMT -4. The time now is 15:09.