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

Boundary conditions for a fan simulation

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

Reply
 
LinkBack Thread Tools Display Modes
Old   April 11, 2011, 10:22
Default Boundary conditions for a fan simulation
  #1
Member
 
William
Join Date: Feb 2011
Location: Minnesota USA
Posts: 33
Rep Power: 6
billynoe is on a distinguished road
Hello all,
I am trying to run a simulation with of a fan. Instead of using a dynamic mesh I wanted to do this using two boundaries to simulate a fan. I set the output side of the fan as a constant velocity and the inlet side as a zero pressure. outlet side zerogradient pressure and inlet side zerogradient velocity. This is probably why my sim keeps crashing. I would appreciate any ideas because I'm all out. I have tried several other BC's without success. The reason I don't want to do dymfoam is because I have almost zero cpu and I'm in 2D.
billynoe is offline   Reply With Quote

Old   April 11, 2011, 11:24
Default
  #2
Member
 
William
Join Date: Feb 2011
Location: Minnesota USA
Posts: 33
Rep Power: 6
billynoe is on a distinguished road
I'm thinking fan BC might be good, but gmshtofoam will not allow me to make a patch that has no outside surfaces
billynoe is offline   Reply With Quote

Old   August 18, 2011, 11:38
Default
  #3
Member
 
Sylvain Aguinaga
Join Date: Feb 2010
Posts: 32
Rep Power: 7
Sylvain is on a distinguished road
Hi,

You can either use the fan BC or fanPressure BC

-fan BC: -pressure jump through an interface. The interface is created with the createbaffle utility. see pimpleFoam/TjunctionFan tutorial to see how to make it

-you have two distinct patches which model the inlet and outlet of a fan. the total pressure prescribed is calculated from a fan curve model.

I'm not yet confident with the last one. i made some comparisons between the two of them, and it looks ok, but i'm not sure what the fanPressure BC is exactly doing.

Sylvain
Sylvain is offline   Reply With Quote

Old   June 1, 2012, 10:58
Default
  #4
Member
 
Tibor Nyers
Join Date: Jul 2010
Location: Hungary
Posts: 91
Rep Power: 7
Toorop is on a distinguished road
Hi,

I have successfully created a fan boundary in the cavity case. I have tested it with icoFoam solver, everything seems OK - cavityFan.

I would like to use the buoyantBoussinesqPimpleFoam solver with the same setup, but the fan has no effect - cavityBuoyantFan. I guess the problem is that there in no p equation, so the fan is not doing anything.

Any idea how to get the fan boundary with buoyantBoussinesqPimpleFoam? Thanks!
Attached Files
File Type: gz cavityFan.tar.gz (2.4 KB, 132 views)
File Type: gz cavityBuoyantFan.tar.gz (3.1 KB, 36 views)
Toorop is offline   Reply With Quote

Old   July 8, 2013, 04:06
Default
  #5
New Member
 
soonic's Avatar
 
Peter
Join Date: Apr 2010
Location: Brno, Czech Republic
Posts: 24
Rep Power: 7
soonic is on a distinguished road
Send a message via ICQ to soonic Send a message via AIM to soonic Send a message via Skype™ to soonic
Hello,
did you already succeed in using fan BC with buoyant solvers ? I am interested in solution.

Last edited by soonic; July 9, 2013 at 09:42.
soonic is offline   Reply With Quote

Reply

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
Implementation of boundary conditions for FVM Tom Main CFD Forum 7 August 26, 2014 05:58
Boundary conditions for 2D Navie-Stockes simulation L1011 OpenFOAM 5 December 13, 2012 09:17
Reversing Fan Direction / Cyclic Boundary Conditions dk1 OpenFOAM Running, Solving & CFD 3 October 4, 2010 05:37
Boundary conditions for pipework simulation metro OpenFOAM Running, Solving & CFD 0 August 12, 2010 03:13
Need help about boundary conditions for a francis runner flow simulation Rodrigo Escobar Moragas Main CFD Forum 1 October 26, 1998 09:20


All times are GMT -4. The time now is 00:56.