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

Boundary condition including time derivative

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

Reply
 
LinkBack Thread Tools Display Modes
Old   June 20, 2015, 10:35
Default Boundary condition including time derivative
  #1
New Member
 
invadoria's Avatar
 
Ender Demirel
Join Date: Jun 2009
Location: Turkey
Posts: 16
Rep Power: 10
invadoria is on a distinguished road
Sponsored Links
Hello OF users,
I want to implement a Neumann type boundary condition for the pressure as follows

dp/dx=-p-dp/dt.

Does anyody know how to use this bc in OpenFoam or swak4Foam?
Best regards,
Ender
invadoria is offline   Reply With Quote
Sponsored Links

Old   June 20, 2015, 10:37
Default
  #2
Senior Member
 
Alex
Join Date: Oct 2013
Posts: 334
Rep Power: 14
zfaraday will become famous soon enough
This is a fixed gradient BC
__________________
Web site where I present my Master's Thesis: foamingtime.wordpress.com

The case I talk about in this site was solved with chtMultiRegionSimpleFoam solver and involves radiation. Some basic tutorials are also resolved step by step in the web. If you are interested in these matters, you are invited to come in!
zfaraday is offline   Reply With Quote

Old   June 20, 2015, 10:44
Default
  #3
New Member
 
invadoria's Avatar
 
Ender Demirel
Join Date: Jun 2009
Location: Turkey
Posts: 16
Rep Power: 10
invadoria is on a distinguished road
Quote:
Originally Posted by zfaraday View Post
This is a fixed gradient BC
Boundary condition depends on the first order time derivative of the pressure. I don't know how to use this time derivative term in the expression.
invadoria is offline   Reply With Quote

Old   June 20, 2015, 14:02
Default
  #4
Senior Member
 
Alex
Join Date: Oct 2013
Posts: 334
Rep Power: 14
zfaraday will become famous soon enough
Forget about what I said in the last post, fixedGradient can't be used to suit your needs, I missunderstood the term Neumann you used... However, it can be achieved by using swak4foam and using the value for pressure from the last time step and the current one.

Best regards,

Alex
__________________
Web site where I present my Master's Thesis: foamingtime.wordpress.com

The case I talk about in this site was solved with chtMultiRegionSimpleFoam solver and involves radiation. Some basic tutorials are also resolved step by step in the web. If you are interested in these matters, you are invited to come in!
zfaraday 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
High Courant Number @ icoFoam Artex85 OpenFOAM Running, Solving & CFD 11 February 16, 2017 14:40
Domain Imbalance HMR CFX 5 October 10, 2016 05:57
Time dependant pressure boundary condition yosuke1984 OpenFOAM Verification & Validation 3 May 6, 2015 06:16
Micro Scale Pore, icoFoam gooya_kabir OpenFOAM Running, Solving & CFD 2 November 2, 2013 14:58
vorticity boundary condition bearcharge Main CFD Forum 0 May 14, 2010 11:32

Sponsored Links


All times are GMT -4. The time now is 16:56.