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

UDF for transient boundary condition?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   November 20, 2003, 22:06
Default UDF for transient boundary condition?
  #1
Shankar
Guest
 
Posts: n/a
Hello everybody,

If I treat the flow through U-tube as a transient problem, can I have a boundary condition (pressure inlet at the left handside and H left > H right) which will be a transient boundary condition, because as water level in the right hand limb keeps increasing there is a drop in the pressure as time progresses and flow would stop at delta H =0.

This boundary condition I have formulated needs to calculate the volume of the water entering the inlet. Is it possible to write an UDF for this which would need the volume of water entering to be read from FLUENT.

Or do you have any suggestions?

Best Regards, Shankar.
  Reply With Quote

Old   November 22, 2003, 08:10
Default Re: UDF for transient boundary condition?
  #2
ccc
Guest
 
Posts: n/a
hi Shankar,

I am not very clear about your problem, but only for the caculation fo the volume of water entering the inlet, it is possible to do it with udf.

first you can get the flux on the inlet by multiplying the velocity and the aera and then integrating the flux along the time gives you the volume.

good luck.

btw, the following macros can be helpful,

F_U, F_V, F_W, F_AERA, NV_DOT,
  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
mixed inflow/outflow downstream boundary condition question peob OpenFOAM Running, Solving & CFD 2 August 14, 2014 09:07
Resolved: Changing boundary condition with UDF according to pressure outlet boundary alpemre Fluent UDF and Scheme Programming 12 February 24, 2014 10:18
Boundary Condition Types Using Scheme and UDF Nasir FLUENT 0 September 15, 2008 21:54
UDF for the boundary condition Sridhar FLUENT 3 July 13, 2001 19:18
UDF : boundary condition ID Flav FLUENT 4 June 28, 2001 09:52


All times are GMT -4. The time now is 11:24.