CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

define BCs at inlet and outlet for natural ventilation simulation

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

Reply
 
LinkBack Thread Tools Display Modes
Old   January 29, 2013, 16:50
Smile define BCs at inlet and outlet for natural ventilation simulation
  #1
New Member
 
Join Date: Jan 2013
Posts: 7
Rep Power: 4
jjz2013 is on a distinguished road
Hi guys,
I want to model a cfd model to simulate the buoyancy flow in a building (inlet at the lateral ground level and outlet at the top). I have some huzzy concepts about defining pressure boundary conditions at inlet and outlet of the building. Any comment and suggestion is welcome. Thank you, guys!

1. According to Fluent 12.0 manual, it says: once the gravity is activated, the pressure will be redefined by adding a hydrostatic head in its original form. I wounder weather this redefiniton is automatically performed by Fluent. So, I still set a zero gauge pressure at inlet and oulet, and Fluent will add a hydrostatic heat in form of -rho0*g*h at the outlet pressure. Is that correct?

2. If there is an external wind horizontally blowing the building, I guess we should consider an additional dynamic pressure at the opennings (inlet and outlet) of the building. A pressure drop occurs between inlet and outlet when the wind blows over the building. How to incorporate this effect in cfd model if I want to just define a boundary at the inlet and outlet surfaces. What i know are the heat source in the building, the wind direction (assuming perpendicular to inlet surface) and velocity, the openings area and orientation.
jjz2013 is offline   Reply With Quote

Reply

Tags
cfd, natural ventilation, wind

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
How to define the turbulence intensity and mixing length at an outlet (for k-eps)? david39 OpenFOAM Running, Solving & CFD 6 February 2, 2011 04:01
p & U outlet bcs for realistic wind inlet profile stevek OpenFOAM 4 July 19, 2010 02:29
VOF Outlet boundary condition in cfd - ace JM Main CFD Forum 0 December 15, 2006 09:07
How to define a inlet and outlet In MixSim where_pc FLUENT 0 February 26, 2006 13:06
what the result is negatif pressure at inlet chong chee nan FLUENT 0 December 29, 2001 06:13


All times are GMT -4. The time now is 01:01.