CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT > Fluent UDF and Scheme Programming

UDF for Rotation

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 18, 2014, 11:52
Default UDF for Rotation
  #1
New Member
 
Giovanni
Join Date: Sep 2014
Posts: 5
Rep Power: 12
Johnmuddy is on a distinguished road
i'm looking for a function that allows to rotate the body between two corners according to the flow.
i'ts a dynamic mesh whith smoothing and remeshing.
the time step is 0.001
end the center of rotation is (0,0)
this is the 6dof function

Quote:
DEFINE_SDOF_PROPERTIES (Rotazione, prop, dt, time, dtime)
{
prop[SDOF_MASS] = 0.01;
prop[SDOF_IZZ] = 0.00833;
prop[SDOF_ZERO_TRANS_X] = TRUE ;
prop[SDOF_ZERO_TRANS_Y] = TRUE ;
prop[SDOF_ZERO_TRANS_Z] = TRUE ;
prop[SDOF_ZERO_ROT_Y] = TRUE ;
prop[SDOF_ZERO_ROT_X] = TRUE ;
printf ("\n2d_Rotazione: Updated 6DOF properties");
}
Now i need to rotate betwen 55° and 5° .
this is the error that fluent gives me end what appens to the mesh
Cattura.jpg

Please help me !
Johnmuddy is offline   Reply With Quote

Old   November 20, 2014, 10:04
Default
  #2
New Member
 
Giovanni
Join Date: Sep 2014
Posts: 5
Rep Power: 12
Johnmuddy is on a distinguished road
Please, anyone can help me? thanks in advance...
Johnmuddy is offline   Reply With Quote

Old   November 21, 2014, 08:10
Default
  #3
New Member
 
Linh Tuan The Nguyen
Join Date: Nov 2012
Posts: 9
Rep Power: 14
linh nguyen is on a distinguished road
Did you tried to reduce under relaxation factor? It's might take longer running time, but might solve the problem
linh nguyen is offline   Reply With Quote

Old   November 21, 2014, 13:22
Default
  #4
New Member
 
Giovanni
Join Date: Sep 2014
Posts: 5
Rep Power: 12
Johnmuddy is on a distinguished road
Quote:
Originally Posted by linh nguyen View Post
Did you tried to reduce under relaxation factor? It's might take longer running time, but might solve the problem
which particular parameter i have to reduce ?

I think the problem that causes negative volumes is due to the fact that I don't have imposed a limit on the rotation as the cells at the edges deform excessively. Anyone knows how to do it ?

i posted the image of the initial condition of the valve, and what i want to do it
and what happens instead.
before.jpg
what appens.jpg
Johnmuddy is offline   Reply With Quote

Old   November 22, 2014, 07:10
Default
  #5
New Member
 
Giovanni
Join Date: Sep 2014
Posts: 5
Rep Power: 12
Johnmuddy is on a distinguished road
Now i'm able to make the simulation without volume errors . but i'm not able to define the angle limits on rotations.

I thought, bypassing the problem, to describe the boundaries on the translation of the center of gravity of the wing so that when it reaches one of the limits of this interval, have v = 0 .. but what macro should i use end how?

Last edited by Johnmuddy; November 22, 2014 at 08:18.
Johnmuddy is offline   Reply With Quote

Old   October 25, 2016, 09:44
Default
  #6
New Member
 
Wesley liu
Join Date: Mar 2016
Posts: 18
Rep Power: 10
luna125 is on a distinguished road
could you describe your solution on how to solve the negative volume?
luna125 is offline   Reply With Quote

Reply


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
Dynamic Mesh UDF Qureshi FLUENT 7 March 23, 2017 08:37
Source Term UDF VS Porous Media Model pchoopanya Fluent UDF and Scheme Programming 1 August 28, 2013 07:12
UDF parallel error: chip-exec: function not found????? shankara.2 Fluent UDF and Scheme Programming 1 January 16, 2012 23:14
How to add a UDF to a compiled UDF library kim FLUENT 3 October 26, 2011 22:38
UDF...UDF...UDF...UDF Luc SEMINEL FLUENT 0 November 25, 2002 05:03


All times are GMT -4. The time now is 19:17.