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

Non-uniform Boundary Conditions

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

Like Tree8Likes

Reply
 
LinkBack Thread Tools Display Modes
Old   June 16, 2014, 18:11
Default
  #21
New Member
 
zahra
Join Date: Jun 2014
Location: Iran-Tehran
Posts: 28
Rep Power: 4
zahraa is on a distinguished road
Hello,
I am new to openFoam and C++ .I want to use codedFixedValue for a wall with convection boundary condition. for this boundary i have used energy balance and with convection BC i have found following equation.


Ts= c1*(c2* Ta+Ti )

In this equation Ts is the temperature of the boundary and Ta is the ambient temperature and Ti is the internal adjacent cell temperature(internal adjacent cell which is next to the boundary) and c1 and c2 are constant.
now i do not know how i can find Ti and how i should define it here in codedFixedValue . and i should know normal distance between internal adjacent cell center and the boundary, how should i do this?
zahraa is offline   Reply With Quote

Old   September 8, 2015, 07:41
Default
  #22
New Member
 
Tomladian Bucinara
Join Date: Jan 2015
Posts: 18
Rep Power: 3
Tom123 is on a distinguished road
Hello ajnewman,

I found these replies may provide a solution for the problem that I am struggling with, but I need your help as I am inexperienced in C++.

The non uniform inlet boundary condition for my problem could not be expressed in a mathmatical fomula, but only listed in a excel table that provides the coordinates and the corresponding velocity components. It is something like below:
x y z ux uy uz
1 0 0 0.1 0.6 0.8
2.5 0.1 0 0.1 0.5 2
3 0.2 0 0.2 0.7 2.8
...

The first three components tells location (z component is 0 for this surface) and the remaining three components are the velocity components.
I do not know how to apply the data to the inlet boundary condition. Any help would be greatly appreciated.

Tom
Tom123 is offline   Reply With Quote

Old   October 5, 2015, 03:31
Default timeVaryingMappedFixedValue
  #23
Member
 
Divyaprakash
Join Date: Jun 2014
Posts: 36
Rep Power: 4
Divyaprakash is on a distinguished road
Why can't we use timeVaryingMappedFixedValue here? Although I am not too sure what does interpolation in time mean here.
Divyaprakash is offline   Reply With Quote

Reply

Tags
non-uniform bc

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 set uniform heating boundary condition? Sargam05 OpenFOAM 0 September 11, 2012 10:09
Need help with boundary conditions: open to atmosphere Wolle OpenFOAM 2 April 11, 2011 07:32
Pressure instability with rhoSimpleFoam daniel_mills OpenFOAM Running, Solving & CFD 44 February 17, 2011 18:08
Boundary condition setting for non-premixed combustion using reactingFoam skyopener OpenFOAM 0 May 23, 2010 22:55
A problem about setting boundary conditions lyang Main CFD Forum 0 September 19, 1999 18:29


All times are GMT -4. The time now is 00:31.