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

Velocity profile boundary condition at inlet

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 28, 2016, 17:10
Default Velocity profile boundary condition at inlet
  #1
Member
 
Sheikh Ahmed
Join Date: Dec 2015
Location: South Carolina, USA
Posts: 88
Rep Power: 10
sahmed is on a distinguished road
Hello Foamers
I have a basic question of which you probably know the answer- suppose I have a radial velocity profile, say a fully-developed parabolic velocity profile, and I want to use this profile as my inlet boundary condition. How can I add this profile as my boundary. This can be by reading magU Vs. Z values from a file, or by reading a parabolic function (z-dependent) or by any other way.

I am quite sure someone of us used this or similar boundary in his/her works. Please suggest me to figure out this.
Thanks in advance.
sahmed is offline   Reply With Quote

Old   June 29, 2016, 03:51
Default
  #2
New Member
 
Justin Wiegmann
Join Date: Aug 2015
Posts: 20
Rep Power: 11
SirIsaac90 is on a distinguished road
Quote:
Originally Posted by sahmed View Post
Hello Foamers
I have a basic question of which you probably know the answer- suppose I have a radial velocity profile, say a fully-developed parabolic velocity profile, and I want to use this profile as my inlet boundary condition. How can I add this profile as my boundary. This can be by reading magU Vs. Z values from a file, or by reading a parabolic function (z-dependent) or by any other way.

I am quite sure someone of us used this or similar boundary in his/her works. Please suggest me to figure out this.
Thanks in advance.
Hi sahmed,

It is quite easy with groovyBC from swak4Foam package, which you could download here.

The BC could then looks like (parabolic with velocity in x-direction):

Code:
Inlet
{         type                         groovyBC;
          value                        uniform (1 0 0);
          variables                    "Um=1; ypos=pos().y; zpos=pos().z; h=-max(pts().z); c1=-Um/(h*h); c2=Um;";     
          fractionExpression           "1";
          valueExpression              "vector(c1 * ((ypos*ypos)+(zpos*zpos)) + c2, 0, 0)"; }
I think the definition is self-explanatory.

Regards
JW
SirIsaac90 is offline   Reply With Quote

Reply

Tags
inlet boundary condition, parabolic function, velocity profile

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to export velocity profile and load it as inlet condition wangy16 FLUENT 38 March 13, 2019 06:43
Linear Velocity Inlet Boundary Condition in Openfoam shahilc OpenFOAM Pre-Processing 1 February 27, 2016 03:00
UDF: Change boundary condition. Velocity inlet to pressure inlet at time "t" jpina FLUENT 10 April 11, 2015 14:19
An error has occurred in cfx5solve: volo87 CFX 5 June 14, 2013 17:44
Pressure Inlet Boundary Condition Profile arapha FLUENT 0 April 4, 2011 16:23


All times are GMT -4. The time now is 07:52.